Glossary

10 repetition max (10RM): The maximal weight that can be safely lifted for 10 repetitions through the entire range of motion. (22)

1-inch partial stand: A short-sitting position in which the individual leans forward and raises the buttocks slightly (about 1 inch) off the supporting surface, bearing all weight on the lower extremities with the hips and knees in a flexed position. [See short sitting.] (35)

1 repetition max (1RM): The maximal weight that can be safely lifted for 1 repetition through the entire range of motion. (22)

Abducens nerve: Cranial nerve IV, supplies motor innervation to the lateral rectus muscle to abduct the eye. (7)

Abnormal synergies: Also called mass patterns, these movement patterns seen after neurological injury are characterized by lack of isolated control with abnormal timing and sequencing of muscle activation. (6,15,25)

Accessory nerve: Cranial nerve XI, supplies motor innervation to the sternocleidomastoid and upper fibers of the trapezius muscles. (7)

Acidosis: A decrease in blood pH due to excessive hydrogen ions (H+). Respiratory acidosis is due to respiratory dysfunction in which accumulated carbon dioxide (CO₂) is converted to carbonic acid releasing H+. (12)

Action stage: In the Transtheoretical Model (Stages of Change) the person has changed his or her overt behavior for less than 6 months. (16)

Active participation: A critical element that is needed for the acquisition of skilled movement; an intervention in which the participant actively attends to and participates in an activity, as opposed to being a passive recipient. (28)

Active range of motion (AROM): The ability of a person to use muscle contractions to move a body segment through the motion available at the joint. (6, 23)

Active-assisted range of motion (AAROM): The ability of a person to use muscle contractions to move a body segment through the motion available at the joint with assistance. (6)

Activities of daily living (ADL): Aspects of daily self-care such as grooming, dressing, bathing, toileting, and transfers. (10, 33)

Activity: A term from the International Classification of Functioning, Disability and Health (ICF) model to describe the ability to complete a total body task, skill, or action. (1)

Activity limitations: Difficulties an individual may have in executing activities. (3)

Acupuncture: A form of Chinese alternative medicine in which fine needle tips are inserted superficially into the skin at specific predetermined locations for therapeutic benefit. (19)

Acute pain: Pain that is of sudden onset accompanying injury to the body, generally declining over a relatively short period of time. (28)

Adaptability: Global modifications of the basic locomotor pattern specifically designed to match the regulatory features of the task and environment (Patla, 1997). (37)

Adenosine triphosphate (ATP): A compound used to store energy in muscles. Energy is released when the molecule is broken down by hydrolysis into adenosine diphosphate and phosphorus. (11)

Adherence: The degree to which a person's decisions, actions, and behaviors correspond with the agreed upon recommendations of a health care provider. In contrast with the term "compliance" adherence denotes an active partnership between the patient and health care professional in a patient-centered approach, consistent with the biopsychological model. [See compliance.] (16, 28)

Adiadochokinesia: A specific component of ataxia; inability to perform rapidly alternating movements. (6)

Aerobic capacity: Maximum amount of oxygen that can be absorbed by the blood; used as a measure of fitness. (11)

Aerobic exercise: Structured and repetitive physical activity performed for extended periods and at sufficient intensity to elicit long-term adaptations. (32)

Aerobic metabolism: Metabolic processes or reactions in the body that require oxygen. (11)

Affect: Behavioral indicator of a person's emotional state. (28)

Afferent: Nerve impulses that convey information centrally toward the central nervous system. (5, 26)

Age-equivalent score: In standardized, norm-referenced testing, the mean chronological age represented by a certain test score. (13)

Ageotropic: Eye movements (away from the ground) that occur in the horizontal plane when the patient is supine and the head is rotated to the left or right sides. (8)

Aging: Undergoing change as a result of the passage of time; the process of getting older. (13)

Agnosia: Difficulty recognizing familiar objects or faces. (4)

Agonistic reversal: A combination of concentric, isometric, and eccentric contractions emphasizing muscles on one side of a joint. For example, in bridging (lifting the hips off of the support surface from a supine position), the patient concentrically lifts into a bridge, which is isometrically held, followed by a slow eccentric contraction when lowering the hips to the surface. (34)

Agraphia: Inability to write. (4)

Alertness: The degree to which a patient is awake, aroused, and attentive. (4)

Alexia: Difficulty comprehending written language. (4)

Algorithms: Procedures or processes of rules for decision-making or problem-solving. (2)

Alkalosis: An increase in blood pH from insufficient number of circulating hydrogen ions. (12)

Allodynia: An exaggerated or painful response to a stimulus that is not typically painful. (5, 28)

Alternating hemianesthesia: Absence of sensation from one side of the body combined with absence of sensation from the opposite side of the face, most likely from a unilateral, lateral brainstem pathology. (7)

Alternating hemiplegia: Weakness or paralysis of one half of the body and the opposite side of the face, mostly likely from a unilateral, medial brainstem pathology. (7)

Alternating isometrics (AIs): Isometric contractions facilitated by the therapist that alternate rhythmically from one side of the joint to the other without relaxation between contractions; used when an individual has difficulty holding or maintaining a joint position and to improve stability in weight-bearing positions. (24, 34, 35)

Ambidextrous: The condition of being equally able to use each hand or the lack of clear hand dominance. (33)

Anaerobic metabolism: Metabolic processes or reactions in the body that do not require oxygen. (11)

Anaerobic threshold: The exercise intensity at which lactic acid starts to accumulate in the bloodstream. (32)

Analgesia: Pain relief. (28)

Anesthesia: Partial or complete sensory loss resulting from disease, injury, or pharmaceutical effect. (5, 27)

Anhedonia: A component of depression, noted by loss of interest in and enjoyment of pleasurable activities. [See depression.] (16, 28)

Anisocoria: Condition of having pupil sizes unequal when comparing right to left. (7)

Ankle strategy: The biomechanical response to maintain equilibrium in quiet standing through minimal tibial movement at the ankle joint. (9, 30)

Ankle-foot orthosis (AFO): An orthosis worn inside the shoe to provide support at the ankle joint, enhancing alignment, safety, stability, and functional mobility. (17, 24)

Anomia: The inability to recall the name of a familiar object. (5)

Anosmia: Complete absence of the sense of smell. (7)

Anosognosia: Condition in which the patient has no self-awareness regarding his/her deficit; will usually deny a problem exists. (4, 31)

Anterograde amnesia: Loss of memory related to events after brain trauma. (4)

Anticipated problems: Deficits that the therapist feels may occur in the future if an intervention is not provided. (2)

Antidromic: In sensory nerve conduction testing, stimulating proximally while recording distally. (12)

Aphasia: An acquired disorder of language, affecting the production or comprehension of speech and the ability to read or write, resulting from neurological impairment. (4, 31)

Appiani maneuver or Gufoni maneuver to the unaffected side:

A therapeutic intervention for treating vestibular dysfunction related to horizontal canalithiasis. (29)

Apprehension: Anxiety and voluntary resistance that results from 90-degree abduction and maximal external rotation in an individual with glenohumeral instability. (6)

Approach signals: Signs indicating an infant is ready for interaction including cooing, smiling, sustained focus, relaxed limbs, and soft pleasant facial expressions. (4)

Approximation: Compression of joint surfaces used as facilitation for co-contraction or stability around a joint. (15)

Apraxia of speech: Inability to say sounds and/or words on a voluntary basis. (31)

Apraxia: The inability to perform tasks or naturalistic actions in the absence of sensory, motor, or coordination deficits. (4)

Aquatic exercises: Exercises that use the hydrostatic properties of water to facilitate strengthening and achieve other therapeutic objectives. (22)

Areflexia: An absence of muscular reflex activity usually associated with flaccidity. (6)

Arousal: A state of being awake; physiologic readiness for activity. (4)

Arteriovenous O₂ (AVO₂) difference: The difference in oxygen content between arterial and mixed venous blood. (32)

Arthrodesis: Permanent immobilization of a joint. (19)

ASIA Impairment Scale (AIS): International Standards for Neurological Classification of Spinal Cord Injury created by the American Spinal Injury Association (ASIA). Five impairment levels:

• AIS A: Complete. No sensory or motor function is preserved in the S4 and S5 segments.

• AIS B: Sensory Incomplete. Sensory but not motor function is preserved below the neurological level and includes S4 and S5; no motor function is preserved greater than three levels below the motor level on either side of the body.

• AIS C: Motor Incomplete. Motor function is preserved at the most caudal segments for voluntary anal contraction, OR the patient meets criteria for AIS B and has some sparing of motor function more than three levels below the ipsilateral motor level on either side of the body. Less than half of the key muscles below the neurological level have a muscle grade greater than or equal to 3/5.

• AIS D: Motor Incomplete. Motor incomplete status as defined in AIS C, with at least half (half or more) of the key muscles below the neurological level having a muscle grade greater than or equal to 3/5.

• AIS E: Normal. Sensory and motor function are normal. (26)

Aspiration pneumonia: Inflammation or infection of the lungs that results from particulate matter from the pharynx entering the airways. (11)

Assistive technology device: "Any item, piece of equipment, or product system, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities" (Assistive Technology Act of 2004, Section 3.4). Assistive technology devices include communication devices, adaptive equipment (e.g., standers, wheelchairs), environmental control devices, adapted computers, and specialized software. (17)

Assistive technology professional (ATP): A service provider who analyzes the needs of individuals with disabilities, assists in the selection of the appropriate equipment, and trains the consumer on how to properly use the specific equipment. The term applies to individuals with national certification from the Rehabilitation Engineering and Assistive Technology Society of North America (RESNA). (17)

Assistive technology service: "Any service that directly assists an individual with a disability in the selection, acquisition, or use of an assistive technology device" (Assistive Technology Act of 2004, Section 3.4). (17)

Associated reactions: Movements which occur involuntarily during movement in other body segments; occur after a central nervous system insult. (15)

Astasia: A specific component of ataxia; an inability to maintain stance that results from incoordination during weight-bearing. (6)

Asthenia: A generalized loss of strength and energy; weakness. (21)

Asymmetrical tonic neck reflex: One of the early tonic reflexes seen in infants; with head turning, increased extensor tone is observed in the extremities on the "face" side and increased flexor tone in the extremities on the "skull" side; usually integrated by 6 months of age in typically developing infants. (13, 19, 34)

Ataxia: A lack of muscle control or coordination of voluntary movements; most often related to cerebellar damage. (20, 21)

Atelectasis: Collapse of alveoli, impairing gas exchange. (11)

Athetosis: Slow, writhing, "worm-like" involuntary movements, particularly of distal extremities and tongue with meaningless movements that flow from one to the other, including muscles not typically involved in a particular movement. (20)

Attention: Cognitive process of one's ability to focus without distraction, maintain concentration over time, complete more than one task at a time, and quickly shift from one task to another. (4, 31)

Attitude toward the behavior: The factor in the Theory of Planned Behavior that, along with subjective norm and perceived behavioral control, determines the individual's behavioral intention with respect to a target health behavior. (16)

Attractor state: A preferred movement pattern or posture used to perform a common activity; a state or behavior toward which a dynamic system tends to evolve.

Autoantibodies: Immunoglobulins (antibodies) that are produced against and cause damage to a patient's own cellular antigens. (12)

Autogenic inhibition: The agonist alpha motor neuron is inhibited because of stimulation of Golgi tendon organs. (15)

Autonomic dysreflexia: A syndrome that most commonly affects individuals who have a spinal cord injury above the T6 level; characterized by an uncontrolled sympathetic nervous system response (including extreme hypertension, intense headaches, and profuse sweating) to a noxious stimulus below the level of the injury. This is considered a medical emergency due to risk of cerebral vascular accident. (11, 26, 32)

Autonomous practice: According to the American Physical Therapy Association, autonomous physical therapist practice "is characterized by independent, self-determined, professional judgment and action" within the context of collaborative practice among the members of the health-care team. (16)

Autotopagnosia: A form of agnosia characterized by inability to recognize body parts and their relationship to each other. [See agnosia.] (4)

Avatar: A virtual simulation or observed representation of a body part, usually a limb. (25)

Avoidance signals: Natural cues that a baby uses to communicate an increasing level of stress including evading eye contact, facial grimacing, yawning, frowning, tongue thrust, and a stop sign position of the hand and arms. (4)

Awareness: Having knowledge of something; the ability to perceive or be aware of a fact, occurrence, or event. (4)

Axon degeneration: Breakdown or destruction of nerve axons. (12)

Axonotmesis: An intermediate form of traumatic injury (often due to sustained pressure or crush) to a peripheral nerve with damage to the axon and myelin sheath, but sparing of the outer coverings of the nerve; degeneration distal to the point of injury; regeneration usually spontaneous and of good quality. (26)

Babinski sign or reflex: A neurological sign that is normally present in infants but when observed in children older than 2 years or adults is often associated with an upper-motor neuron lesion; observed as great toe extension and toe splaying that results from stroking the ventral aspect of the foot. (6)

Bad Ragaz Ring Method (BRRM): A form of aquatic therapy that incorporates peripheral neuromuscular facilitation (PNF). (15)

Balance confidence: An individual's self-efficacy for maintaining his or her balance. (16)

Balance: Physical equilibrium in an upright posture; maintaining the center of mass over the base of support to remain upright in a given environment and during a specified task. (8, 9, 30)

Balanced sitting: Ability to control the center of mass over the base of support in a seated position while performing voluntary tasks and reacting to external perturbations. (10)

Ballismus: Uncontrollable, violent, flailing movements of an entire limb. It is typically unilateral and might also blend with choreoathetosis. (20)

Barbecue roll maneuver (Lempert maneuver): A commonly used vestibular intervention designed to treat horizontal canalithiasis; the therapist rapidly positions the patient's head, considering the position of the horizontal canal in order to move the canalith, a small sandlike particle, back into position. [See canalithiasis.] (29)

Basal ganglia: A group of five nuclei (caudate nucleus, putamen, substantia nigra, globus pallidus, subthalamic nucleus) that lie deep with the cerebrum. The basal ganglia have no direct connection with the spinal cord but directly and indirectly influence motor pathways by way of the thalamus through connections with many areas of the frontal cortex. (20)

Base of support (BOS): All points of body contact with the supporting surface, which can be described as the area enclosed within the perimeter of all these points of contact. (9, 30)

Behavioral belief: The belief that performing a given behavior is associated with certain attributes or outcomes; along with evaluation of behavioral outcome, it determines the individual's attitude toward the behavior in the Theory of Planned Behavior. (16)

Behavioral contract: A document used in constraint-induced movement therapy, signed as a formal agreement by the therapist, patient, and caregiver, and establishing what the patient is going to do (and not do) routinely with the affected upper extremity when she is not in therapy. (33)

Behavioral intention: The factor in the Theory of Planned Behavior that determines an individual's performance of a target health behavior. (16)

Behavioral state: Infant's level of alertness and ability to react and respond to stimuli, often described as quiet sleep, active sleep, sleep-wake transition, quiet alert, active alert, and crying (high stress). (4,13)

Bell's palsy: Unilateral dysfunction of cranial nerve VII with paralysis of the upper and lower face on the affected side. (7)

Benign paroxysmal positional vertigo (BPPV): The most common form of vertigo, characterized by an episodic (paroxysmal), subjective sense of spinning, which is consistently initiated for each patient by some specific change in the position of the head; thought to be caused by debris (otoconia) that has collected within the inner ear canals. (8, 29)

Berg Balance Scale (BBS): A 14-item scale to measure static and dynamic balance and associated risk for falling; item-level scores range from 0-4 with a maximal possible total score of 56. (9)

Best practice: The delivery of optimal and efficient care using the most helpful resources to work toward optimal recovery of function. (1)

Biofeedback: A therapeutic technique in which some bodily function is monitored and displayed to the patient as auditory or visual stimuli so the patient can use the information for training/learning purposes (e.g., muscle activity in a specific muscle group is monitored and displayed via surface electrodes that detect electromyographic (EMG) signals so the patient can voluntarily adjust her motor performance according to the feedback). (24)

Biomedical model: The traditional model of healthcare in which illness is explained on the basis of purely biologic factors. (16)

BIOnic Neuron (BION): Wireless and implantable micro muscle stimulator about the size of a grain of rice. (18)

Biopsychosocial model: A more recent model of healthcare, based on systems theory, which considers the interactions among biologic, psychological, and social factors as determinants of health and illness. (16)

Bitemporal hemianopsia: Loss of the temporal or lateral visual field from each eye. (7)

Blood gases: Clinical laboratory measures of oxygen, carbon dioxide, blood pH, and related measures in arterial blood samples. (12)

Blood pressure: The pressure in arterial blood vessels, measured as systolic (peak of the cycle after each heartbeat) and diastolic (the lowest point in the cycle). (11)

Bobath therapy (also known as neurodevelopmental treatment, or NDT): A problem-solving approach to the assessment and treatment of individuals with disturbances of function, movement, and tone to optimize posture and movement with practice of functional activities. [See neurodevelopmental treatment.] (25)

Body image: Visual/mental memory of one's body, i.e., whether tall/short; slim/plump. (4)

Body mass index: A calculation based on an individual's height and weight as an indication of body composition, particularly body fat. (16)

Body scheme: Postural model of one's self, the body parts in relation to one another. (4)

Body structure/body function: A term from the International Classification of Functioning, Disability and Health (ICF) model describing normal structure and functioning of the body's organs and systems. (1)

Body Weight Support (BWS): A percent of the patient's body weight is supported through an overhead suspension system during ambulation. This results in decreased weight/force through the lower extremities during gait and prevention of falls. (15)

Body weight–supported treadmill training or body weight– supported ambulation training: Ambulation training in which some portion of the patient's body weight is supported by an external harness/suspension system while walking on a treadmill or over ground. (24, 37)

Bradycardia: Slow heart rate (less than 60 beats per minute). (11)

Bradykinesia: Slow movement; a symptom of Parkinson disease. (20)

Braid-walking: Sideways stepping in which one foot steps over and across the stance foot rather than just "stepping to." (30)

Brandt-Daroff exercises: Vestibular exercises to help the patient habituate, get used to, or tolerate abnormal vestibular perceptions and experiences. (29)

Bridging: A position in supine in which the hips and knees are bent so the feet are flat on the supporting surface and the hips are raised off the surface. (34)

Broca's aphasia: Expressive aphasia characterized by halting speech primarily composed of content words. (31)

Bulbar: An adjective anatomically referring to the brainstem excluding the midbrain, and especially referring to the medulla oblongata. (7)

Bulbar symptoms: Abnormal expressions of cranial nerve function, especially forms of motor paralysis (bulbar palsy) of the face, mouth, pharynx, and esophagus often related to medulla pathology, with impaired facial expression, speech production and swallowing. (7)

Buoyancy: Upward pressure exerted by a fluid that opposes the weight of an immersed object (e.g., body) so that it can float. (19)

Cachetic: Malnourishment, weight loss, severe muscle wasting, and frailty. (11)

Calibration test: Performed as part of electronystagmography (ENG) or videonystagmography (VNG) to assess rapid eye movements. (8)

Caloric test: Performed as part of electronystagmography (ENG) or videonystagmography (VNG) to measure inner ear responses to warm and cold water or warm and cold air circulated through a small, soft tube in the inner ear of the horizontal canal. (8)

Canalith repositioning maneuver (CRM): A therapeutic intervention specifically for benign paroxysmal positioning vertigo (BPPV) in which the therapist rapidly repositions the patient's head, considering the orientation of the dysfunctional semicircular canal in order to move the canalith, a small sandlike particle, to an area of the canal where it will not cause problems. (29)

Canalithiasis: A form of benign paroxysmal positioning vertigo in which the otoconia are freely mobile in a semicircular canal. (8)

Cardiac output: The amount of blood pumped by the heart each minute; the product of stroke volume and heart rate. (32)

Cardiac preload: Stretching force the heart must overcome at end of diastole. (11)

Cardiorespiratory fitness (exercise capacity): The capacity to withstand the physiological stresses of prolonged exercise. (32)

Casani maneuver or Gufoni to the affected side: A modified Semont maneuver for vestibular intervention to treat horizontal canal cupulolithiasis. (29)

Cataracts: Condition in which the lens of the eyes become cloudy or opaque, obscuring vision. (7)

Catastrophizing: A type of pain cognition in which an individual tends to focus on the worst case scenario, drawing extremely negative conclusions or making extremely negative predictions that are not warranted by or are out of proportion to the circumstances at hand; associated with mood disorders, particularly depression, and chronic pain and indicative of poor coping skills. (28)

Causalgia: [See Complex regional pain syndrome.] (28)

Cawthorne-Cooksey exercise: A set of specific progressive exercises incorporating eye movements that progress to head movements, combined with progressively more challenging postures (sitting, standing, walking); primarily indicated for patients with vestibular system or vestibular labyrinth impairment to facilitate habituation to abnormal vestibular perceptions. (21, 29)

Cellular respiration: The process of breaking down nutrients through oxidation to produce energy in the form of ATP. (11)

Center of mass (COM) or center of gravity (COG): The single location on the supporting surface where the gravitational line, passing through the center of mass, would strike the floor or other supporting surface; COM and COG are the same if the gravitational field is equally distributed. (9, 30, 37)

Center of pressure (COP): The point of application of the ground reaction force that is equal and opposite to the forces acting downward on a force plate in the vertical, horizontal, and transverse planes. (37)

Central pain: Pain that is caused by a central nervous system lesion. (28)

Central pattern generators (CPGs): Interneurons located in the spinal cord that execute simple flexion and extension movements without input from higher centers in the central nervous system. (25)

Central vestibular deficit: Disorder of the central vestibular system that results in dizziness or other vestibular symptoms. (29)

Central vestibular system: The subsystem within the central nervous system comprising the vestibular nuclear complex, spinal cord, cerebellum, reticular formation, thalamus, and cerebral vestibular cortex. (8, 29)

Cerebral autoregulation: The intrinsic ability of cerebral vessels to maintain a relatively constant, steady-state blood flow. (32)

Cerebral palsy (CP): A group of nonprogressive but permanent disorders in the development of movement and posture from injury to the developing fetal or infant brain, causing activity limitations. (25)

Cerebral shock: A temporary occurrence of flaccidity early after upper-motor neuron lesions of the cerebrum and brainstem following cerebrovascular accident, which may last for days to weeks. (6)

Cerebrovascular accident (CVA): Ischemia of brain tissue that results from embolus, thrombus, or cerebral hemorrhage. (11)

Cervical-ocular reflex: A reflex in which the neck position acts through feedback from neck proprioception to cause stereotypic eye movements. (29)

Chaddock sign: A neurological sign similar to the Babinski sign but involving great toe extension and splaying that occurs in response to noxious stimulation of the dorsolateral aspect of the foot as opposed to the ventral surface. [See Babinski.] (6)

Chemistry: Laboratory measures of levels of specific chemicals in serum and other body fluids. (12)

Chorea: An involuntary movement that is an abrupt, variable, and random flow of activity from one body part to another. Movements are arrhythmic, forcible, rapid, and jerky but can appear dance-like or "choreographed." The unpredictable nature distinguishes chorea from dystonia and tremor. (20)

Choreoathetosis: Chorea and athetosis are often indistinguishable. A combination of the two movements typically occurs with damage or disease of the basal ganglia. Therefore many clinicians will describe the movement as choreoathetosis. (20)

Chronic pain: Ongoing or recurrent negative sensory experience resulting from injury or pathology, lasting more than 3 to 6 months, which adversely affects the individual's well-being; often related to inflammation. (5, 28)

Chronotropic incompetence: The inability of the sinoatrial node to respond to the metabolic demands of exercise. (32)

Circulatory hypokinesis: Reduction in venous return and stroke volume, which impairs delivery of oxygen and nutrients to and removal of metabolites from exercising muscles. (32)

Clasp-knife phenomenon: A characteristic of spasticity, inconsistently present, in which the passive stretch results in initial resistance followed by sudden release as seen when opening a spring-loaded pocket knife. (6)

Clients: In the Guide to Physical Therapist Practice (APTA, 2003), individuals who are receiving consultative (i.e., nonclinical) services. (1, 16)

Clinical decision-making: A complex process of analytical thinking to determine appropriate examination methods and design and customize specific intervention techniques and treatment activities. (1, 2)

Clinical laboratory test: Analysis of a clinical specimen (tissue, body fluid, stool, sputum, etc.) performed by highly trained medical laboratory professionals to assess patient health status and aid in the diagnosis, treatment, and monitoring of disease. (12)

Clinical practice guidelines: Evidence-based or consensus-based principles/guides to direct health-care practice and patient care. (2)

Clinical reasoning: The decision-making process displayed by health-care professionals when working to resolve a problem. (2)

Clonus: A rhythmic involuntary contraction that occurs in response to quick stretch of a muscle in the ankle (most common), wrist, or patella; indicative of central nervous system impairment. (6, 19)

Closed chain exercise: Weight-bearing postures in which the body moves over a fixed distal segment. (22)

Closed loop systems: Controlling movement by using input from particular types of sensory information as movement is executed. (25)

Closed movement task: Task performed in a relatively fixed environment that is unchanging. (25)

Closed task: A task that is performed with little variability between trials, such as standing up or standing in a quiet room. (36)

Cocontraction or coactivation: The simultaneous contraction of agonists and antagonists around a joint to stabilize the joint; can impair functional movement if not appropriately sequenced or timed. (6, 18, 24, 25, 32)

Cognition or cognitive processes: Mental processes involved in the ability to think, learn, and remember; the basis for how we reason, judge, concentrate, plan, and organize. (4, 13, 31)

Cogwheel rigidity: Muscular rigidity in which passive movement of the limbs through the available range elicits ratchet-like start and stop movements. (6, 19)

Coma: The level of consciousness in which the patient cannot be roused, even with noxious stimuli. (4)

Combination of Isotonics: Technique in which a concentric contraction of the agonist muscles is resisted through the range of motion, immediately followed by an isometric hold, and then a resisted eccentric contraction through the reverse range of motion to the starting position; no relaxation occurs between the three types of muscle contractions. (15)

Communication: An exchange of ideas including both verbal and nonverbal modes; interactions may include speaking, listening, gesturing, reading, and writing, or using augmented devices such as keyboards as processes to successfully convey messages. (4, 31)

Compensation: Intervention that encourages complex brain changes to allow cerebral adjustment to altered sensory input and abolish the perception of vestibular symptoms. (29)

Compensatory approach: Retraining a task or skill using alternative strategies, movement substitution, or assistive devices or equipment. (36)

Complementary movement approaches: Alternative types of exercise used to enhance strength, balance and efficiency of movement; often incorporate breathing patterns and relaxation. Examples include tai chi, yoga, Feldenkrais Method, and aquatic therapy. (15)

Complete paralysis: A total and permanent loss of voluntary motor function in at least one region of the body. (26)

Complete spinal cord injury: According to the ASIA Impairment Scale (AIS): International Standards for Neurological Classification of Spinal Cord Injury created by the American Spinal Injury Association (ASIA), complete paralysis indicates no sensory or motor function in the lowest sacral segment of the spinal cord, S4 and S5. [See ASIA Impairment Scale (AIS). (26)

Complex regional pain syndrome: A chronic pain syndrome in which the affected extremity becomes exquisitely painful, often characterized by reports of burning pain. There are four domains of dysfunction: sensory (onset of hyperalgesia, allodynia, or both); vasomotor (changes in skin temperature, skin color, or both); sudomotor/edema (changes in sweating, onset of edema, or both); and motor/trophic (onset of motor dysfunction and/or trophic changes of the hair, nails, or skin). The etiology is poorly understood, and the condition is challenging to treat. Onset can be insidious or can follow injury (often minor) to the affected body part, stroke, neuropathy, or radiculopathy. (28)

Type 1 (reflex sympathetic dystrophy): No known nerve injury. (28)

Type 2 (causalgia): Known nerve injury. (28)

Complex repetitive discharges (CRDs): In an electromyo-graphic study, bursts of repetitively discharging muscle fibers that start and stop abruptly. (12)

Complexity: The number of component parts of a skill and the information processing demands associated with the skill. Highly complex skills have many component parts and require a high degree of information processing. (37)

Compliance: The degree to which a person's decisions, actions, and behaviors follow an established plan that is dictated by the health-care provider in an authoritarian, rather than collaborative, approach to healthcare. (16, 28)

Compound muscle action potential (CMAP): The summation of a group of almost simultaneous action potentials from several muscle fibers in the same area, usually evoked by stimulation of the supplying motor nerve, as in a nerve conduction study. (12)

Compound muscle action potential (CMAP) amplitude: The multi-peaked summated action potential recorded in a motor nerve conduction study. (12)

Compound muscle action potential (CMAP) area: In a motor nerve conduction study, the area under the waveform (in mV/ms). (12)

Compound muscle action potential (CMAP) duration: In a motor nerve conduction study, the time from the initial deflection to the next baseline crossing, reflecting the synchrony of muscle fibers firing at the same time. (12)

Compound muscle action potential (CMAP) latency: In a motor nerve conduction study, the time (in milliseconds) from the stimulus onset to the initial deflection of the CMAP. (12)

Computed tomography (CT): An imaging technique in which the source x-radiation is rotated around the patient, then using computer analysis presents visual images of relative tissue densities of the target tissue. (12)

Concentric training: Contraction as the muscle shortens, which involves moving a load through a partial or complete range of motion; the force developed by a muscle exceeds the magnitude of the external force, resulting in shortening of the muscle. (22)

Concurrent feedback: Feedback that is given to a patient while he/she is performing a movement or task. (36)

Concurrent validity: Results of a particular test coincide with the results of an accepted measurement standard. (13)

Conduction block: The nerve conduction study shows that no impulses travel along the nerve. (12)

Conduction slowing: The nerve conduction study shows that impulses travel along the nerve at a decreased rate as seen with demyelination. (12)

Cones: The color receptors of the retina with very high visual acuity, most highly concentrated in the fovea centralis. (7)

Conjugate eye movements: Coordinated tracking movement of both eyes such that they move nearly precisely in the same direction at the same time and at the same velocity and magnitude. (7, 8)

Consensual light reflex: Shining a penlight into the pupil of one eye results in constriction of the contralateral pupil. (7)

Constraint mitt: A covering for the hand used in constraint-induced movement therapy, similar to a glove but with a single compartment for all the fingers; for this therapeutic application, the mitt is placed to restrict the person from using the non-affected limb. [See constraint-induced movement therapy.] (33)

Constraint-induced movement therapy (CIMT): An intervention approach designed to increase use of a more-impaired extremity by physically constraining the uninvolved extremity. The type of constraint, time in constraint, and duration of therapy may vary and are established on an individualized basis. The main categories of intervention are repetitive, task-oriented movement training; adherence enhancing strategies (i.e., the transfer package); and constrained (e.g., encouraged) use of the more-impaired extremity. (15, 25, 33, 37)

Construct validity: Test adheres to accepted theoretical constructs. (13)

Contemplation: Stage in the Transtheoretical Model (Stages of Change) in which the person intends to take action within the next 6 months. (16)

Content validity: Test is a complete representation of the concept of interest. (13)

Continuous task: A task that has no distinct beginning, middle, or end point; it includes tasks such as standing, walking, swimming, and biking. (25, 36, 37)

Contract relax (CR): A technique used to increase range of motion; an agonist pattern is brought to its end range limited by tightness of the antagonist pattern; the therapist resists a strong isometric contraction of the antagonists while allowing isotonic rotation to occur, followed by an isometric hold and then voluntary relaxation when the patient actively moves into the new range or the agonist pattern. (15)

Contractile: The muscle with its tendons and attachments. (23)

Contracture: Limitations in passive range of motion that occurs because of tightness in the muscle, joint capsule, or other soft tissue. (6, 23)

Control belief: The perceived likelihood of occurrence of each facilitating or constraining condition; along with perceived power, it determines the individual's perceived behavioral control in the Theory of Planned Behavior. (16)

Control parameters: Factors or variables that strongly influence how a given task or skill is performed. Internal control parameters are factors within the individual that influence the task, such as joint motion or muscle strength. External control parameters (also known as regulatory environmental features) are factors that influence the movement within the environment, such as the height of a chair or angle of the ground. (36)

Controlled mobility: The ability to control movement over a stable base of support (e.g., weight shifting or movement in weight-bearing postures). (15, 35)

Convergence: Ocular movement in which the two eyes each adduct, moving toward each other, observed when a visual target moves closer to the face. (7, 8)

Coordination: A subset of motor control, specifically related to cooperation between opposing muscle groups at a joint during movement (one grading on while the opposing group is appropriately grading-off). (21)

Coping: The process of managing stress and meeting the challenges of stressful situations (e.g., by modifying the environment, changing self-talk, increasing assertiveness). (28)

Corneal reflex: Touching the cornea of one eye with a single fiber from a cotton ball results in rapid closure of the eyelids bilaterally. (7)

Cortical deafness: Result of bilateral lesion of auditory cortex in which sounds are heard but cannot be interpreted, however, reading and writing are preserved. (4)

Cost/benefit ratio: The value of a particular measure to the patient and/or facility compared with the cost of conducting the measure. (10)

Counting Talk Test: A semiquantitative measure of exercise intensity in healthy adults based on how high the exercising person, at rest (as a baseline) or while exercising, can count aloud before taking a second breath. (32)

Cranial nerve (CN): The peripheral nerves that emerge directly from the brain or brainstem to innervate structures of the head, face, neck, and some body organs including the cranial parasympathetics. (7)

Cranial ultrasound: Imaging studies that use sound frequencies as the energy source and capture the reflected sound to generate an image of the soft tissue being examined. (12)

Crawling: Locomotion on the floor in the prone position using primarily elbows and knees to propel, with the abdomen in contact with the floor. (34)

Creeping: Locomotion in quadruped (on hands and knees) with the abdomen up off the floor or supporting surface. (34)

Criterion-referenced: Test scores are interpreted on the basis of absolute criteria (e.g., the number of items answered correctly) rather than on relative criteria (e.g., how the rest of a standardized sample performed). (13)

Critical power: The maximal rate of work that can be endured indefinitely. (32)

Critical values: Clinical laboratory test results that indicate a potentially life-threatening pathophysiological condition requiring immediate notification and medical attention. (12)

Crossed-ankle sitting: Sitting on the floor with the legs folded in toward the body and the legs crossed at the ankle or calf. The feet remain on the floor and may be tucked under the knees or thighs. (35)

Cross-training: Principle that promotes prescribing a range of muscle performance demands in a strength training program, such as varied types of muscle contractions, speeds, and muscle strength and endurance components, to promote more generalized muscle capabilities. (22)

Cupololithiasis: A form of benign paroxysmal positional vertigo in which the otoconia are attached to the cupula. (8)

D1 flexion (D1F): A designated movement pattern in peripheral neuromuscular facilitation (PNF). In the upper extremity the movement combines scapular elevation, abduction, upward rotation; shoulder flexion, adduction, external rotation; it may or may not include elbow flexion; forearm supination; wrist and finger flexion; thumb adduction. In the lower extremity the movement combines pelvic protraction; hip flexion, adduction, external rotation; it may or may not include knee flexion; ankle dorsiflexion, inversion; toe extension. (34)

Decision delay: Phenomenon in which people with acute stroke or other major adverse health events do not emergently seek treatment upon the initial onset of the signs and symptoms. (16)

Declarative or explicit memory: Memory of facts and events that can be consciously recalled or declared and explicitly stored and retrieved. [See explicit memory.] (4, 31)

Decoding: Interpreting a message as a listener or receiver of communication. (31)

Decomposition (of movement): One component of ataxia observed as irregularity in performing a movement: a limb movement that normally involves simultaneous multi-joint actions that are smooth and continuous is broken down into sequential, non-continuous segments, perhaps one joint at a time. (6, 21, 25)

Deconditioning: A loss of physical fitness, including aerobic capacity, due to failure to maintain an optimal level of physical activity or training. Inactivity for any reason, including bedrest, may lead to deconditioning. (11, 16, 32)

Deep brain stimulation: Unilateral or bilateral electrical stimulation most often delivered through an implanted electrical stimulation unit with embedded electrodes in the areas around the thalamus. (19)

Deep pressure: Manual pressure across the longitudinal axis of the muscle tendon causing relaxation of the muscle. (15)

Deep sensations: Sensory feedback related to position or movement of a joint or body segment. (5)

Deep tendon reflex (DTR): Tested as a measure of neurological status; involves striking a muscle tendon, which provides a sudden stretch/elongation of the muscle, to see if an appropriate reflexive contraction occurs of the same muscle. (6)

Delayed feedback: Feedback that occurs after the movement/skill has been completed rather than during the movement itself. When a patient moves sit-to-stand, delayed feedback might occur 15 seconds after he gets to standing. (36)

Delirium: The state of consciousness, acute and transient, consisting of a variety of cognitive symptoms such as confusion, inattention, altered consciousness and orientation, disorganized thought and perception, and hallucinations. (4)

Demyelination: Disorders in which the myelin of nervous system fibers is broken down or destroyed. (12)

Depression: A mood disorder characterized by morbid sadness, dejection, or melancholy, involving a range of signs and symptoms including anhedonia (a loss of interest in and enjoyment of pleasurable activities). (28)

Dermatomal distribution: A configuration of tactile sensory deficit in which the loss appears in the pattern of a dermatome; a band of skin without (or with decreased) sensation and related to sensory innervation by a single nerve root. (5)

Dermatome: A region of skin whose sensory information is received by a single spinal nerve root. (5)

Developmental quotient: Ratio between the individual's actual score or developmental age on a test and the individual's chronological age. (13)

Diagnosis: A label encompassing a cluster of signs and symptoms, syndromes, or categories that represent the impact of a health condition on function at the level of a body system or at the level of the whole person. Physical therapy diagnosis is specifically related to aspects within the scope of physical therapy practice. (2)

Diagnostic imaging: Any of the entire array of imaging methods to create a view of a particular internal structure. (12)

Diagnostic ultrasound: Studies in which sound frequencies, used as the energy source, are captured and used to generate an image of soft tissue. (12)

Diastolic blood pressure: The lowest level of arterial blood pressure during the diastole (relaxation) phase of the cardiac cycle. (11, 32)

Differential count: Part of a hematology report in which the laboratory will report the breakdown of types of white blood cells (lymphocytes, neutrophils, monocytes, basophils, eosinophils) as percentage of total white blood cells. (12)

Diplopia: Double vision, often resulting from an abnormal positioning of one eye; in horizontal diplopia the two images are side-by-side; in vertical diplopia, the two images are vertically oriented one above the other. (7)

Direct light reflex: Shining a penlight into the pupil of one eye results in constriction of the same pupil. (7)

Disability: In the National Center for Medical Rehabilitation Research (NCMRR) model, an inability to fulfill certain life roles at a social level. (1, 10)

Disablement model: A conceptual framework for understanding complex pathways from active pathology or disease to various types of functional consequences that can be used as a guide for a therapist's analysis and clinical reasoning. (2)

Disconjugate eye movements: [See Nonconjugate eye movements.]

Discreet task: A task that has a distinct beginning, middle, and end; this includes such tasks as sit-to-stand, stand-to-sit, and transferring from a wheelchair to a bed. (25, 36)

Dissociation: Separation of parts; for example, trunk rotation or counterrotation separating the shoulder and pelvic girdles. (10)

Distal latency: In a motor nerve conduction study, the latency obtained by stimulating the nerve at the most distal site. (12)

Divergence: Abduction of both eyes as the visual target moves further from the face. (8)

Dix-Hallpike position or test: Vestibular testing position in which the patient rapidly lies backward from long-sitting to a position with the head hanging over the edge of the plinth with 45-degree neck rotation and ~20-degrees of neck extension. (8, 29)

Dizziness: A nonspecific term that refers to a sense of unsteadiness and feeling as if one may fall. (8, 29)

Domains of function: Specific tasks or activities examined by a particular outcome measure. (10)

Dorsal rhizotomy (selective dorsal rhizotomy): A surgical approach to spasticity management in which afferent nerve rootlets contributing to spasticity are identified via electrical stimulation and excised. (19)

Double support phase: Phase of gait in which both feet are on the ground. (10)

Dual task interference: The decrement in performance of a skill when another skill, either physical or mental, is added. (37)

Dual task: A complex skill condition in which performance of a primary task, usually a motor functional skill that is the major focus of attention for the individual, is carried out concurrently with a secondary task, which may be physical or mental. (37)

Durable medical equipment (DME): Equipment that is used for medical purposes and that can stand repeated use; generally speaking, in the absence of a medical problem, injury, or illness, DME is not necessary. (17)

Dynamic balance: Maintenance of an upright posture during self-initiated body or body-segment movement. (9, 30)

Dynamic systems theory: A developmental theory that concep-tualizes motor development as the result of a dynamic interplay between mechanical, neurological, cognitive, and perceptual factors within the individual and the variable aspects of the environment and the task. (13)

Dynamometry: The objective measurement of muscle strength using a device (dynamometer) that measures force, torque, or power. (6, 7)

Dysarthria: Neurologically based impairment of motor control that results in slow, slurred, or less-coordinated speech that is difficult to understand or less natural sounding. (4, 20, 21, 31)

Dysdiadochokinesia: A specific component of ataxia, this type of dyskinesia consists of decreased ability to perform rapidly alternating movements (e.g., forearm pronation/supination, wrist flexion/extension, ankle dorsiflexion/plantar flexion). (6, 21)

Dysesthesia: Sensory impairment in which an ordinary stimulus results in a negative disagreeable sensation such as burning; contrast with paresthesia. (5, 28)

Dysfunction: Abnormal function of an organ, system, or structure. (3)

Dyskinesias: Abnormal movement disorders arising from pathology in the basal ganglia. (20)

Dysmetria: One component of ataxia, in which the patient misjudges the movement needed to reach a target, with resulting inaccuracy in touching or placement; may be observed as overshooting (passing the target) or undershooting (stopping short of the target). (6, 21, 25)

Dysphagia: Impaired ability to swallow; may occur in conjunction with dysarthria. (20, 31)

Dyspnea: Difficulty breathing. (11)

Dystonia: An abnormal condition in which a disorder of the basal ganglia results in persistent muscle contraction and unintended repetitive movements and distorted positions of the body; can be focal or generalized. (19, 20)

Dyssynergia: A specific component of ataxia: the incoordination of antagonist muscle groups. (6)

Easy Street environment: Indoor life-size replica of a city street that includes a grocery store, car, and architectural barriers as well as a home with a kitchen and bedroom; used to simulate the public and home environments. (10)

Eccentric training: Contraction as the muscle elongates; the external force exceeds the force developed by a muscle, resulting in lengthening of the muscle. (22)

Ecological assessment: A comprehensive process in which data about how a child functions in different environments or settings are collected. (13)

Efferent: Impulses that convey information away from the central nervous system toward an effector organ (muscle or gland). (5, 26)

Elbow-locking mechanism: Biomechanical locking of the elbow in extension, with the hand in weight-bearing (closed kinetic chain) and activation of the anterior deltoid and upper pectoral muscles combined with shoulder external rotation. (35)

Electrical stimulation (ES): Therapeutic delivery of an electrical stimulus by electrodes that causes contraction of motor units within a target muscle group. (19, 24)

Electrolytes: Substances, which can be found in the blood serum, that dissociate into positively and negatively charged particles (ions) in body fluids. (12)

Electromyographic biofeedback (EMGBFB): Adjunct for retraining activation of weak muscles by providing the patient with enhanced visual or auditory feedback regarding the activation and timing of muscle recruitment during task training. [See electromyography.] (22)

Electromyography (EMG): A test that uses a device to measure muscle activity by reading the electrical signals the muscle produces via a needle that is inserted into the muscle or surface electrodes over the muscle. (6, 12, 37)

Electrophysiologic test: A test that directly or indirectly measures physiological activity of the nervous system. (12)

Electromyographic target threshold: The minimum amount of muscle activation needed to trigger an auditory or visual biofeedback signal during electromyography. (22)

Electromyographic (EMG)-triggered neuromuscular electrical stimulation (NMES): A combination of NMES with EMG biofeedback that allows the clinician to adjust the threshold of voluntary muscle activation required by the patient to trigger NMES to augment muscle tension. (22)

Enablement model: A model that guides the therapist to identify and explore the patient's skills and resources available to assist them in their roles and participation in activities. (2)

Encephalomalacia: An area of softening of the brain (resulting from liquefactive necrosis) secondary to infarction or injury. (12)

Encoding: Converting a thought/idea into communication that is sent to another. (31)

End feel: The resistance encountered at the end of the available ROM. (6)

Endplate noise: In needle electromyography (EMG), irregularly firing monophasic negative potentials, 10 to 50 μV in amplitude, firing at 20 to 40 Hz, that occur if the needle is inserted at the endplate region. (12)

Endplate spike: In needle electromyography, irregularly firing monophasic negative potentials, 10 to 50 μV in amplitude, firing at 20 to 40 Hz, that occur if the needle is inserted near a terminal nerve twig. (12)

Endurance: Ability to continue a submaximal activity over a period of time. (11)

Enzymes: Proteins, which can be measured in the blood serum, that catalyze the biochemical reactions that make life possible. (12)

Epley maneuver: The most common canalith repositioning maneu-ver, used to treat posterior or anterior canal canalithiasis associated with benign paroxysmal positional vertigo (BPPV). (29)

Equilibrium (balance) reactions: Relatively sophisticated automatic postural responses that occur in response to substantial displacement of the center of mass; used in combination with righting and protective reactions. (9, 13, f35)

Equilibrium sensibility: The ability to sense the position and movement of the head in space, conveyed by cranial nerve VIII. (7)

Equilibrium: A state of balance within a system resulting in stability. (30)

Error magnification: Resistance to moving in the desired direction. (25)

Essential components: Individual parts of a total movement pattern that allow efficiency in task performance. (10)

Evaluation: The dynamic, cerebral process in which the therapist makes clinical judgments about patient status, based on the data gathered from the examination. (2, 3)

Evaluation of behavioral outcome: The value attached to the attributes or outcomes of performing a given behavior; along with behavioral belief, it determines the individual's attitude toward the behavior in the Theory of Planned Behavior. (16)

Evidence-based practice: Clinical practice in which decisions are governed, as much as possible, with a basis in prevailing scientific evidence and also practitioner expertise and patient values. (1, 24)

Evoked pain: Pain that is stimulus dependent. (28)

Evoked response: The physiological activity that results from stimulation of a peripheral nerve. (12)

Examination: The process of conducting patient history, relevant systems review, and tests and measures to collect data on the patient's condition as a basis for decision-making. (2, 3)

Executive function: Integration of cognitive processes to plan, organize, and execute the necessary steps to successfully meet a goal. (4, 31)

Exercise duration: The overall length of a training program. (22)

Exercise frequency: Number of sessions per day and per week. (22)

Exercise intensity: Determined primarily by exercise load or level of resistance, but also influenced by the interaction of the rate of movement and the type of muscle action required; can range from submaximal to maximal intensity. (22)

Exercise volume: The total exercise dose, determined by the total number of repetitions and sets during an exercise session. (22)

Existing problems: Deficits that the therapist determines currently interfere with the patient's participation level and therefore, if appropriate, an intervention should be introduced to address. (2)

Expanded Disability Status Scale: An assessment used to rank functional loss on a 0 to 10 scale in persons who have multiple sclerosis. (25)

Expert clinician: An experienced individual who possesses optimal content knowledge with the ability to reason in order to solve clinical problems, including reflection on his/her own experience. (1)

Explicit memory: Recall in which tasks require conscious awareness and control. [See declarative memory.] (4)

Explicit training: Training that focuses on the instructions for a movement, such that the rules of the movement are clearly stated and the learner focuses on these rules. (36)

Expressive aphasia: Significant deficits in use of language to express oneself (e.g., use of telegraphic sentences while speaking). (31)

Extension phase of sit-to-stand: The third phase of sit-to-stand when the knees and hips extend to move the center of mass upward to full standing. (36)

Extraocular muscles: The six muscles that insert into specific locations on the surface of the eyeball and generate movements of the eyes. (7)

Extrinsic factors: In relation to falls, factors external to the individual that might precipitate a fall (e.g., uneven surfaces). (9)

Extrinsic feedback: Feedback that is given by another person or object (e.g., scale, buzzer, or mirror) to an individual learning a motor task. (36)

Eye-head movements between two targets: An exercise using repetitive eye saccades in each direction to substitute for an impaired vestibulo-ocular reflex. (29)

Facial nerve: Cranial nerve VII, receives taste from anterior 2/3 of tongue and supplies motor innervation for muscles of facial expression. (7)

Facilitation technique: Intervention that increases the capacity to initiate a movement through increased neuronal activity or stimulation of muscle activation/recruitment. (18, 22)

Fall prevention/risk reduction: An intervention strategy that includes patient/client education, physical intervention, and environmental adaptation to minimize the likelihood of loss of balance and resulting uncontrolled descent to the ground or other support surface. (16)

Family-centered care: For intervention with children, the delivery of care is focused around the values of the family. (24)

Fasciculation potential: In an electromyographic study, the spontaneous (i.e., involuntary) discharge of a motor unit. (12)

Fast break: Velocity during walking that is reduced by approximately 90%, with the final 10% reduction occurring in the final break period. (37)

Fast brushing: High-frequency brushing that provides sensory input to C fibers of the skin overlying a muscle resulting in stimulating muscle activation or recruitment. (18)

Feedback control: Corrective postural control of movement to regulate and adapt movement in dynamically unstable situations to maintain a safe position, to be dynamically stable, or to correct inaccurate goal-directed movement. (21)

Feedforward control: Compensatory postural responses that are taking place in anticipation of a potentially destabilizing activity, or an activity requiring greater skill than what the neuro-muscular-skeletal system is capable of performing and initiates compensatory movement. (21)

Feldenkrais Method®: Considered an alternative approach for somatic education to enhance one's awareness of movement. (15)

Fetal ultrasound: A test used during pregnancy that uses reflected sound waves to produce a picture of the fetus, the placenta, and amniotic fluid; the resulting picture can contribute to evaluating the health and physical structure of the fetus. (12)

Fibrillation potential: The electrical activity associated with the spontaneous contraction of a single muscle fiber due to instability of the muscle fiber membrane. (12)

Finger-to-finger test: A test of coordination (cerebellar function) in which the patient is asked to abduct his/her arms and then bring his/her hands in front of the body to touch the tips of the index fingers; can do with eyes open or closed. (6)

Finger-to-nose-to-finger test: A test that assesses nonequilibrium coordination of the upper extremities through precision movements of the upper extremity to voluntarily bring the patient's index finger into contact with the patient's own nose, then to the therapist's finger, and then alternating between the two. (6)

Frequency Intensity Time and Type (FITT) equation: A general formula for outlining a treatment plan, including frequency, intensity, time, and type of therapeutic intervention. (2)

Fixation test: Performed as part of the rotary chair test to measure nystagmus during fixation on a stationary target while the patient is being rotated. (8)

Flaccidity: A complete lack of muscle tone, typically associated with complete or total lower-motor neuron lesions. (6, 18)

Flexibility (muscle flexibility): The length and extensibility of musculotendinous structures that cross a particular joint and their influence on the ability of the joint to move. (6)

Flexion momentum phase of sit-to-stand: The first phase of sit-to-stand when the trunk moves forward over the feet (base of support). (36)

Flow cytometry: Laboratory measures that analyze body fluids for the identification of cell population subsets using a flow cytometer. (12)

Fluent aphasia: Communication impairment characterized by difficulty understanding language but retaining speech production with a normal rhythm, melody, and articulation. (4)

Foot tapping: A test for dysdiadochokinesia with rapidly alternating movements of ankle plantar flexion and dorsiflexion. (6)

Force platform: A computerized instrument that measures the ground reaction forces during standing or moving by a person, and can be used to quantify balance and gait. (9)

Forced use: Intervention as part of constraint-induced movement therapy (CIMT) in which the patient's uninvolved extremity is physically restrained forcing the use of the involved extremity to complete motor tasks. [See constraint-induced movement therapy.] (15, 37)

Forced-prolonged positioning: A vestibular intervention to treat horizontal canal benign paroxysmal positional vertigo (BPPV) in which the patient must sustain a specific position for 12 hours to try to move otoconia. (29)

Fractionation: The ability of the individual, through motor control, to move the target joint through very small fragments of the available range. (6)

Frenkel's exercises: An exercise protocol to treat patients with ataxia/incoordination, primarily symptoms due to a loss of proprioception as a result of posterior column impairment of the spinal cord but may have application in patients with cerebellar ataxia. (21)

Frenzel lenses: High powered magnifying glasses (often look like ski goggles) that provide magnification of the eyes and their movement for the examiner, while preventing the individual from visually fixating, to optimize observation of nystagmus. (8)

Frog leg posture: Lower extremities positioned with hips in flexion, abduction, and external rotation; typically seen in patients with hypotonia or flaccidity. (18)

Function: The ability of a person to perform whole-body tasks or skills that comprise the usual performance of human individuals. (1)

Functional: Term describing the category that includes skills and actions that support an individual's ability to carry out meaningful activities that are important for participation in life roles. (10, 37)

Functional electrical stimulation (FES): Neuromuscular electrical stimulation applied within a functional activity or task in an organized manner to promote functional motor relearning. [See Neuromuscular electrical stimulation]. (18, 24)

Functional examination: An examination of performance of the specific activities needed in daily life, such as transfers or ambulation. (10)

Functional goals: Specific behavioral objectives that describe the functional performance projected to occur by the end of an intervention or in a specified time period. (1)

Functional independence: The ability to perform daily skills or tasks without depending on help from another person. (10)

Functional limitation: From the National Center for Medical Rehabilitation Research (NCMRR) model, refers to inability at a whole-person level to optimally perform a physical task or activity. (1, 3, 10)

Functional outcomes: The actual changes in functional limitations that result from intervention and other factors. (1)

Functional position (of the hand): The typical position of the wrist, hand, and digits during a functional task. The wrist is positioned in slight extension, the hand is in slight ulnar deviation, and the digits are all slightly flexed with the thumb in opposition to the second and third digits. (33)

Functional Reach Test: Test which measures the maximal distance a standing patient can reach beyond arm's length while maintaining a fixed base of support. (9)

Functional synergies: Muscles working together as a functional unit; some muscles act as prime movers, whereas other muscles act as synergists or stabilizers during the task training. (22)

Functional tasks: Activities performed during daily life that contribute to the overall physical status and well-being of the patient. (10)

Functional training: A type of purposeful physical activity involving practice of a given task for improved neuromotor control. (16)

F-wave: A late response, during a nerve conduction study, evoked by supramaximal stimulation. (12)

Gag reflex: Tactile stimulation to the back of the pharynx (usually with a tongue depressor) results in a gag response. (7)

Gain: a measure provided in the form of a ratio to describe the relationship of eye movement to head movement or eye movement to target movement. (8, 29)

Gait: The specific movement pattern of the arms and legs that enables walking or forward locomotion; the rhythmical, repetitive movement pattern during ambulation distinguished by a characteristic sequence of limb and trunk moves. (37)

Gait cycle: The events of one complete sequence of movements in ambulation, defined as the time from the initial contact of one foot to the next initial contact of the same foot. (10, 37)

Gait velocity: The speed of ambulation; an important and objective functional measure in the examination of balance and equilibrium. (9)

Gas exchange: Passage of oxygen and carbon dioxide between the alveoli of the lungs and the vascular system. (11)

Gaze stability: The ability to fixate on a visual target even during head movements. (8, 9, 29)

Gaze-evoked nystagmus: An abnormal jerky eye movement that is produced when a person gazes, moves the eyes from the center position to an eccentric position in the orbit. (8)

General somatic afferent (GSA): Category of cranial nerves that receive general senses from the face including facial proprioception. (7)

General somatic efferent (GSE): Category of cranial nerves that control voluntary movement of the eyes and tongue. (7)

General visceral afferent (GVA): Category of cranial nerves that receive general sensory input from visceral organs. (7)

General visceral efferent (GVE): Category of cranial nerves that supply involuntary efferents to visceral structures including cranial nerve (CN) III (iris constrictors), CN VII (lacrimal and salivary glands), CN IX (parotid salivary gland), and CN X (parasympathetics to thoracic and abdominal viscera). (7)

Geotropic: Eye movements (toward the ground) that occur in the horizontal plane when the patient is supine and the head is rotated to the left or right sides. (8)

GivMohr sling: A patented device used for positioning a flaccid upper extremity (www.givmohrsling.com). (18)

Glossopharyngeal nerve: Cranial nerve IX that carries sensory input from the pharynx, taste and touch from the posterior third of the tongue, and motor innervation to the pharynx. (7)

Goal setting: A type of cognitive skills training in which the individual is taught to set goals that are not only personally relevant but also realistic; a process in which a patient and his health-care provider collaborate to identify treatment goals that are relevant and realistic for an episode of care. (28)

Goals: Intermediate steps in the rehabilitation process that specify: (a) who will perform the behavior, (b) what the specific behavior is, (c) under what conditions the behavior will be performed, and (d) how the outcome will be measured. (2)

Golgi tendon organ: A proprioceptive sensory receptor located at the musculotendinous junction providing information (Ib afferent) about changes in active muscle (contraction) tension. (27)

Gram stains: Microbiologic testing using specific staining techniques and microscopic analysis of color and shape of a bacterium for general identification. (12)

Graphesthesia: The recognition of symbols traced on the patient's palm. (5)

Grasp: Both the position of the hand and fingers as they embrace objects and the action of taking or clasping objects. (33)

Gravitational insecurity: A dysfunction of sensory modulation that could be related to poor sensory processing (vestibular and proprioceptive); observed as a fear of moving, lack of upright position (Bundy, 2002). (27)

Grip: A firm or tight hold on an object. (33)

Ground reaction force: Force exerted by the ground when the foot strikes the ground. It represents an equal amount and opposite direction to the force applied by our feet onto the ground. (37)

Habituation exercises: A category of exercises in which the provoking position or stimulus is repeated until the person no longer has symptoms. (29)

Halliwick Method or Concept: A 10-step approach to aquatic therapy which focuses on mental adjustment, balance control, and movement in the water and culminates with the ability to swim. (15)

Hand dominance: The increased skill and preferential use of one hand over the other in the performance of skilled activities. (33)

Handedness: An individual's hand-use preference or consistent and more proficient use of the right or left hand to perform motor activities. (33)

Handicap: In the National Center for Medical Rehabilitation Research (NCMRR) model, is a societal limitation, constraint, or barrier imposed by society or the environment that prevents full involvement of the individual at a social level. (1)

Haptic robot: A robotic system designed to sense user movements and use the resulting information to make decisions about subsequent movements. Feedback is also provided to the user. (25)

Head-hips relationship principle: The principle in which the hips move in the opposite direction of the head (e.g., when the head moves down, the hips lift up). (35)

Health: According to the American Physical Therapy Association, "(a) state of being associated with freedom from disease, injury, and illness that also includes a positive component (wellness) that is associated with a quality of life and positive well-being." (16)

Health behavior: "Any activity undertaken by a person believing himself to be healthy, for the purpose of preventing disease or detecting it in an asymptomatic stage" (Kasl, 1966a, p. 246; 1966b, p. 531). (16)

Health condition: Term from the International Classification of Functioning, Disability and Health (ICF) model to describe "diseases, disorders, and injuries" (WHO, 2001). (1)

Health disparities: Differences in health indicators and quality of life among groups. (16)

Health education: "Any combination of learning experiences designed to facilitate voluntary actions conducive to health" (Green, 1991, p. 17). (16)

Health promotion: "The combination of educational and environmental supports for actions and conditions of living conducive to health." (Green, 1991, p. 17). (16)

Health psychology: A subdiscipline within psychology defined by Taylor (2009, p. 3) as a "field devoted to understanding psychological influences on how people stay healthy, why they become ill, and how they respond when they do get ill." (16)

Heart rate: The number of heart beats per minute. (11)

Heart rate reserve (HRR): The difference between maximal heart rate and resting heart rate. (32)

Heavy work: Terminology used by Rood referring to the cocon-traction of the tonic muscles to provide stability around a joint or body segment. (15)

Heel-to-shin test: Test of lower extremity coordination in which the patient sits or lies supine and then voluntarily places the heel of the limb being tested along the anterior surface of the contralateral ankle. The patient then slides the calcaneus along the anterior surface of the contralateral tibia up toward the knee and then back down again, repeating this cycle several times. (6)

Hematology: The category of clinical laboratory testing that studies and describes cellular blood composition. (12)

Hemianopsia: Vision loss in the same hemifield of both eyes. (31)

Hemostasis: The category of clinical laboratory testing that provides information on clotting function of the blood. (12)

Heterotopic ossification: The formation of mature, lamellar bone within soft tissues outside the normal bone and joint structures. (23, 26)

Hip strategy: The biomechanical response to an active perturbation, employing flexion or extension of the hip to lower the center of mass and shift the center of mass within the base of support and regain balance. (9, 30)

Hippotherapy: Purposeful manipulation of the movements of a horse to provide the rider with motor, sensory, and cognitive input for therapeutic purposes. (21, 30)

Hold relax (HR): A technique used to increase range of motion; an agonist pattern is brought to its end range limited by tightness of the antagonist pattern, the therapist resists a strong isometric contraction of the antagonists, followed by a voluntary relaxation when the patient actively moves into the new range or the agonist pattern. (15)

Hold relax active movement (HRAM): A movement in which the muscle is brought passively into the shortened range and an isometric contraction is facilitated. After approximately 10 seconds, the patient is told to relax; the therapist quickly and passively moves the muscle into the lengthened range and applies a quick stretch to facilitate active movement toward the shortened range. The therapist then assists or resists achieving the patient's best muscle response. The technique is used when a muscle is weak and a patient has difficulty initiating movement. (34)

Holism: "The perception of the client as a whole person … [whose] overall state of health … [is] a result of a complex interaction of factors including physical, mental, sociocultural, and spiritual components" (CAOT, 1991). (1)

Home diary: A record maintained by the patient and caregiver in constraint-induced movement therapy documenting activities completed with the affected upper-extremity during all waking hours when not in therapy. (33)

Home exercise program: A set of prescribed exercises/activities, also called a home activity program, conducted by the patient at home, either alone or with assistance of a caregiver. (1)

Home practice: Performance of a functional task repeatedly with the affected upper extremity for 15 to 30 minutes in constraint-induced movement therapy. (33)

Home skill assignment: Used in in constraint-induced movement therapy, home activity(ies) assigned to encourage specific use of the affected upper extremity during a variety of different functional activities outside of therapy time. (33)

Homonomous hemianopsia: Loss of one half (one side) of the visual field from each eye usually contralateral to the cortex damage; homonomous implies that the same half is lost from each eye, i.e. loss of the right half of visual field of both eyes following a left cerebral vascular accident. (7)

Horizontal roll or barbeque roll (Lempert maneuver): Exercise in which the patient in a supine position performs a series of head movements toward the affected side, with body rolling eventually back to the starting position, as a treatment for horizontal canal canalithiasis. (29)

H-reflex: The electrophysiologic counterpart of the ankle reflex, measuring latency over the monosynaptic reflex arc through the afferent sensory fibers and efferent motor fibers of the S1 nerve root. (12)

Humeral cuff sling: A device for positioning a flaccid or hypo-tonic upper extremity using an elastic cuff around the humerus as a control point to decrease shoulder subluxation. (18)

Hyperalgesia: A heightened sense of pain in response to stimuli that are normally painful. (28)

Hypercalcemia/Hypocalcemia: Serum calcium levels are increased or decreased, respectively. (12)

Hyperesthesia: Sensory impairment characterized by an excessive or increased sensitivity to sensory stimuli. (5)

Hyperkalemia/Hypokalemia: Serum potassium levels are increased or decreased, respectively. (12)

Hyperkinesis: Excessive movement, often the result of basal ganglia disorder. (20)

Hypermagnesemia/Hypomagnesemia: Serum magnesium levels are increased or decreased, respectively. (12)

Hypermetria: A specific component of ataxia; the inability to judge the distance to a target during movement; results in either stopping short of the target or pass-pointing. (6, 21, 25)

Hypernatremia/Hyponatremia: Serum sodium levels are increased or decreased, respectively. (12)

Hyperopia: Visual deficit in which a person cannot see things clearly up close, sometimes referred to as "far-sighted." (7)

Hypersensitivity: Overreaction to sensory input. (27)

Hypertonia (hypertonicity): According to the National Institute for Neurological Disorders and Stroke (NINDS), a condition in which there is too much muscle tone so that arms or legs, for example, are stiff and difficult to move; caused by damage to aspects of the brain or spinal cord that control muscle tone. A hypertonic muscle will have an increased resistance to passive elongation while it is at rest. (6, 19)

Hypoesthesia or hypesthesia: Sensory deficit characterized by a decrease in sensibility or awareness. (5)

Hypoglossal nerve: Cranial nerve XII that innervates musculature of the tongue. (7)

Hypometria: Undershooting or underestimating the required force for completing a movement task. (21, 25)

Hyposensitivity: Underreaction to sensory input. (27)

Hypothesis-Oriented Algorithm for Clinicians (HOAC): Systematic guide to patient management that includes the following steps: initial data collection, generation of a problem statement, establishment of goals, examination, formation of working hypotheses, reevaluation of goals, establishment of a treatment plan, implementation, and reevaluation (Rothstein, 1986). (2)

Hypotonia (hypotonicity): An abnormal decrease in skeletal muscle tone; resistance less than normal during passive elongation of a muscle. (6, 18)

Hypoxemia: Abnormally low level of oxygen in arterial blood. (11)

Illness behavior: "Any activity, undertaken by a person who feels ill, to define the state of his health and to discover a suitable remedy. The principal activities here are complaining and seeking consultation from relatives, friends, and from those trained in matters of health" (Kasl and Cobb, 1966a, p. 246; 1966b, p. 531). (16)

Image: A visual representation of internal body structures produced by diagnostic imaging methods. (12)

Immunohematology: Laboratory measures that analyze donor and recipient red blood cell antigens and antibodies. (12)

Immunology: Laboratory measures that analyze body fluids for the identification and quantification of antibodies, determination of viral load, and immune function testing. (12)

Impaired interjoint coordination: When the intended synchrony of muscle contractions is disturbed and one or more muscles fire out of sequence. (25)

Impaired termination: Difficulty stopping and/or changing direction of movement. (25)

Impairment: Term from the National Center for Medical Rehabilitation Research (NCMRR) to describe dysfunction at the organ/system level. (1, 3)

Implicit or nondeclarative memory: Recall that does not require conscious awareness of components of the task; seen in more automatic responses. [See nondeclarative memory for synonym; explicit memory for contrast.] (4)

Implicit training: Training that focuses on the learning that comes with repetition and practice; less emphasis is placed on the rules of the task, and more emphasis is placed on repeating the task. (36)

Incomplete spinal cord injury: Partial damage to a particular region of the cord that allows some communication from the brain to segments of the spinal cord below the injury level, with some motor/sensory or autonomic function remaining below the lesion level. Some sensation and/or voluntary motor function is present at S4-S5. (26)

Incoordination (ataxia): Impairment of coordination. (6)

Indirect impairments: Deficits that develop as a secondary complication and not as a direct result of the disease process. (1)

Information processing: A critical element that is needed for the acquisition of skilled movement; the cognitive ability to use available information for problem-solving. (28)

In-hand manipulation: The ability to keep an object in the hand while manipulating it. (33)

In-hand stabilization: The ability to prevent an object within the hand from moving. (33)

Inhibition technique: An intervention method with the purpose of minimizing some abnormal body system function, particularly a positive symptom such as hypertonicity or hypersensitivity, or trying to prevent some abnormal position, posture, or movement. (19)

Initial contact (IC): The time when the foot first strikes the floor to signal the start of the stance phase of gait. (37)

Insertional activity: A brief burst of action potentials that follows the insertion of a needle electrode into muscle. (12)

Instrumental activities of daily living (IADL): Activities that are not necessary for fundamental functioning (e.g., walking, dressing, toileting, transferring); allow an individual to live independently in a community (e.g., shopping, driving, food preparation, home management) and require higher level cognitive and organizational abilities. (10)

Instrumental Gait Analysis (IGA): Computer augmented instrumentation used to analyze gait. (10)

Intention tremor: A component of ataxia, the irregular back and forth movement (from alternating actions of agonist and antagonist) that takes place during voluntary (intended) movement. (6, 21)

Intermittent exercise protocol: Exercise test that utilizes periods of exercise interspersed with a short rest. An example would be asking a patient to exercise 3 minutes and rest for 1 minute and then repeat the cycle. (11)

Interval scale: Equal intervals between categories but no true zero point; may be added or subtracted but cannot be used to interpret. (10)

Intervention: According to the American Physical Therapy Association, "the interactions and procedures used in managing and instructing patients/clients" (APTA, 2001). (1)

Intractable pain: Chronic pain that is difficult to manage (e.g., cancer pain). (28)

Intrathecal baclofen: A method of continuous administration of baclofen antispastic drug into the intrathecal space. (19)

Intraventricular hemorrhage: Intracerebral bleeding into the ventricles and surrounding brain tissue, particularly in premature infants. (12)

Intrinsic factors (related to fall prevention): Risk factors that are within the individual. (9)

Irradiation: The spread of muscle activation from stronger muscles to weaker muscles within a synergistic pattern. (18)

Isokinetic exercise or muscle actions: Voluntary muscle actions occurring with the limb moving at a fixed speed of movement (e.g., 30 degrees per second). This mode of action typically requires computerized equipment to govern movement velocity. The quantity of muscle force produced is proportional to the individual's effort throughout the established range of motion. (6, 22)

Isolated movement: Voluntarily activating only the intended specific muscle groups without any extraneous or unintended movement at related joints. (6, 15)

Isometric muscle actions: Voluntary muscle actions occurring with the limb remaining stationary (static). The quantity of muscle forced produced is variable and ranges from gentle activation of a muscle such as that occurring in a setting exercise up to maximal effort against an immovable object. (6)

Isometric training: The force developed by a muscle equals the magnitude of the external force, resulting in no motion; the patient is asked to sustain a hold against manual resistance to build force-generating capability. (22)

Isotonic muscle actions: Voluntary muscle actions occurring with the limb moving with or without additional resistance. The quantity of muscle forced is proportional to the amount of resistance encountered during the movement. (6)

Items: Measures or task variations to observe. (10)

Jendrassik maneuver: An adjustment to patellar deep tendon reflex testing, with clasping hands and pulling them against each other, which may be used to heighten reflex reaction by increasing upper extremity tension. (6)

Joint approximation: Compression through a joint that can be applied either manually or mechanically to facilitate postural extensors and joint stabilizers. (18, 22)

Joint contracture: Contracture that is due to tightness of the joint capsule structures. [See contracture.] (23)

Joint laxity: Lack of or decreased stability in a joint. (18)

Joint moment: Force application that results in a rotational force around an axis. (37)

Joint passive movement: [See range of motion.] (6)

Joint stability: The ability of a joint, supported by all the tissues surrounding that joint, to resist being moved. (24)

Joint traction: A manual distraction of the limb. (22)

Key points of control: Manual contacts used with neurodevel-opmental treatment (NDT) to facilitate or inhibit desired movements. [See neurodevelopmental treatment.] (15)

Kinematics: The subset of mechanics that describes the motion of objects including displacement, velocity, and acceleration without considering the forces related to the motion. (10, 37)

Kinesio Tape: An elastic therapeutic tape that is designed to mimic the qualities of human skin and might be helpful to control joint position and reduce excitability of spastic muscle fibers. (19)

Kinesthesia: The sensation that allows perception of movement. [See Movement sense.] (5, 27)

Kinetic: Describes the forces acting to produce observed movement patterns. (10, 37)

Knee hyperextension (genu recurvatum): Knee extension that is excessive, beyond full extension, and usually observed in midstance of gait (single-limb support) after cerebral damage. (24)

Knowledge of performance: Feedback that focuses on the quality of the movement, such as the amount of hip/trunk flexion during sit-to-stand. (36)

Knowledge of results: Feedback that focuses on whether the task was achieved rather than on the quality of the task (e.g., when the therapist states, "You just stood up without using your hands."). (36)

Kyphosis: Abnormal increased convexity of the spine; typically in the thoracic spine. (11)

Latency: Refers to the time lapse that occurs when a patient is placed in the Dix-Hallpike position and the onset of vertigo and nystagmus. (8)

Learned nonuse: Behavioral mechanism that results from a period of inability to use a body part (e.g., neural shock after a stroke); the individual is negatively reinforced when using the body part and therefore stops trying, even when use is possible to a certain extent. (15, 25)

Length-tension relationship: The optimal muscle length for maximum tension development. (22)

Lethargic: The state of being drowsy and falling asleep easily. (4)

Letter of medical necessity (LMN): Clinical justification specific to the client and to each component of assistive technology being requested (e.g., armrests, leg rests, seat back, controllers); illustrates or details medical necessity for the client. (17)

Leukocytosis: An increase in the number of leukocytes in circulating blood; often indicates the presence of infection. (12)

Level of consciousness: A continuum in the level of alertness, attention, and awareness that ranges from full wakefulness to comatose. (4)

Lifespan developmental theory: Proposes an aging process continuously and simultaneously influenced by a wide range of dynamic biological and social processes. (13)

Lift: An upper trunk pattern combining bilateral asymmetrical flexion patterns of the upper extremities, with the lead arm completing the D2 flexion pattern while the other arm grasps the wrist of the lead arm, thereby completing a modified D1 flexion pattern. (34)

Light reflex: Shining a penlight into a pupil results in constriction of the pupils. [See direct light reflex and consensual light reflex.] (7)

Light touch: The sensation that results from very slight tactile stimulation. (5)

Light work: Terminology used by Rood referring to the light voluntary work performed by phasic muscles. (15)

Lightheadedness: A subjective term used to describe a feeling of giddiness or feeling "faint" and is usually a less localizing symptom. (8)

Limits of stability (LOS): The maximum distance that a person can intentionally move or displace their center of mass in each direction without loss of balance. (9, 30)

Loading response (LR): Moment in gait when the weight is transferred onto the stance limb. (37)

Locked knee extension: Full knee extension (without hyperex-tension) accompanied by biomechanical locking of the knee, often observed in midstance of gait (single-limb support) after cerebral damage. (24)

Locomotor training (LT) (as in gait retraining): Several variations of LT can be used such as ambulation on a treadmill, body weight supported on a treadmill or over ground, and lower extremity facilitation with manual cues or robotic assistance. (15)

Locomotor training (LT): A physiologically based approach to gait rehabilitation incorporating intrinsic mechanisms of the spinal cord that respond to specific afferent input to produce stepping motions. (25)

Long-sitting: Sitting with both legs straight out in front of the body and parallel to each other. (35)

Long-term goals (LTGs): A statement of expected achievement that specifies (1) who will perform the behavior, (2) what the specific behavior is, (3) under what conditions the behavior will be performed, and (4) how the outcome will be measured. Reflects a limited time span, generally greater than 3 weeks. (2)

Lower motor neuron (LMN) lesion: An injury to a single ventral nerve root, spinal nerve, plexus, or named peripheral nerve resulting in unilateral weakness, loss of sensation, and a decrease in spinal reflexes. (6, 26)

Magnetic resonance imaging (MRI): Diagnostic imaging that uses radiofrequency or sound waves as the energy source, with computer analysis to generate a representative image of the tissue being studied. (12)

Maintenance: Stage in the Transtheoretical Model (Stages of Change) in which the person has changed his or her overt behavior for more than 6 months. (16)

Mal de débarquement syndrome (MdDS): A rare disorder that results in a feeling of rocking or swaying that is worse when still and improves with movement. (29)

Manipulation task: A task that requires use of one or both upper extremities. (25)

Manual contacts: Placement and application of hands-on facilitatory or inhibitory sensory input used to affect the ability to perform a movement or muscle contraction. (18)

Manual muscle testing: A method to assess muscle strength that attempts to isolate specific muscles or muscle groups by placing the patient and the tested joints in various standardized positions. (6)

Massed practice: A continuous form of practice, without rest between repeated performances of a skill; part of constraint-induced movement therapy (CIMT) and other treatment approaches. (33)

Mastication: The motor action of the jaws for chewing of food. (7)

Maximal exercise test: Exercise testing in which a patient exercises to the point of exhaustion or until 85% of age appropriate maximal heart is achieved. (11)

Maximal oxygen consumption (VO₂max): The highest oxygen intake that an individual can attain during physical work, demarcated by the attainment of a "plateau" or point at which further increases in exercise workload are not accompanied by concomitant increases in oxygen consumption. (32)

Mean arterial pressure (MAP): The average arterial pressure during a single cardiac cycle, which is approximately the diastolic pressure plus one-third of the difference between the systolic and the diastolic blood pressure levels. (32)

Mechanoreceptors: Classification of sensory receptors that respond to mechanical pressure. (27)

Medically necessary: "Services or items reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member" (https://www. medicare.gov). (17)

Memory: The ability to initially acquire, store, and recall (remember) information from the past. (4)

Memory loss: Inability to recall (remember) specific information. (31)

Mental practice: Mental practice involves the mental rehearsal of a task without actually moving (rather than actually performing the task). Mental practice is also termed mental imagery and involves the individual viewing himself in the mind's eye performing the task. The patient should be encouraged to view the task in the biomechanically correct view. (36)

Mental status testing: The portion of the neurological exam that assesses mental function, including level of consciousness, attention, language, memory, proverb interpretation, similarities, calculation, writing, and the ability to construct figures. (4)

Metabolic acidosis: Acidic state where pH of the blood falls below 7.4 caused by excess acid added to body fluids or loss of bicarbonate from body fluids. (11)

Metabolic equivalent of task (MET): An expression of the energy cost of a physical activity or task as a multiple of resting metabolic rate obtained during quiet sitting, which by convention is considered 1 MET. (32)

Metabolic syndrome: A constellation of metabolic abnormalities that interact to accelerate the progression of atherosclerosis and increase the risk of developing cardiovascular or cerebrovascular disease. (32)

Microbiology: Laboratory measures that analyze tissues and body fluids for the identification of infectious pathogenic microorganisms (bacteria and fungi), and test cultured pathogens for antibiotic susceptibility. (12)

Mild cognitive impairment (MCI): Subtle changes in memory that are noticeable and can be detected by clinical tests, but do not impair judgment, reasoning, or activities of daily living. (4)

Mind map: A creation using a earning strategy used to expand one's integration of ideas. (2)

Minimal F-wave latency: One of the late responses in nerve conduction studies, this is the most commonly employed F-wave measure, representing the time to fire the largest and fastest motor neurons. (12)

Minute ventilation (VE): The volume of air expired in 1 minute. (32)

Mixed nerve conduction studies: Electrophysiologic testing through a mixed nerve with simultaneous stimulation of sensory and motor axons. (12)

Mobility: The presence of functional range of motion to assume a posture and the presence of sufficient motor unit activity to initiate and sustain active movement through a range of motion. (15, 18, 35)

Mobility task: A task in which the base of support is moving, such as sit-to-stand or walking. (25, 36)

Mobilizations: Passive movements of the articular surfaces at a joint that may be implemented to increase joint range of motion. (23)

Modified Ashworth Scale (MAS): A scale specifically developed to rate the degree of spasticity, noting the magnitude of resistance and the portion of range in which the increased resistance is detected. (6)

Modified plantigrade position: A posture in stance with slight forward inclination that employs upper extremity support. (24)

Modified stand-pivot transfer (or squat-pivot transfer): Alternate term for a partial standing transfer in which the patient moves from one sitting surface to another by weight-bearing on the lower extremities in a partial standing position. (10)

Molecular diagnostics: Laboratory measures that analyze patient DNA for the identification of heritable genetic diseases, tumor characterization, assessment of multigene disease risk and therapeutic drug efficacy, and determine tissue-typing for organ and stem-cell transplantation. (12)

Momentum transfer phase of sit-to-stand: The second phase of sit-to-stand in which weight is shifted from the buttocks to the feet using both momentum and hip/knee muscle forces. It is one of the most unstable phases of sit-to-stand because the base of support is moving from a relatively large area under the buttocks to a smaller area under the feet. (36)

Momentum: The tendency of an object to continue moving once it has been set in motion. (26)

Mononeuropathy: A subtype of neuropathy with disease or dysfunction of a single nerve. (28)

Motivation to comply: The motivation to behave according to each referent's wishes; along with normative belief, it determines the individual's subjective norm in the Theory of Planned Behavior. (16)

Motor activity log: Developed as a research questionnaire for patients and caregivers to report activities of daily living performed with the affected upper extremity after stroke. (15, 33)

Motor conduction studies (MCS): Electrophysiologic testing by stimulating distal and proximal sites along the course of the peripheral nerve while recording the evoked motor response with surface electrodes from a muscle innervated by the stimulated nerve. (12)

Motor conduction velocity (MCV): The velocity of nerve transmission across a specific segment of a peripheral motor nerve. (12)

Motor control: The process by which the brain organizes and regulates action of the muscular and skeletal systems, including movement and dynamic postural adjustments of a joint or body segment. (6, 24, 25)

Motor control-movement (or motor control for movement or movement control): All aspects of motor control related to the muscles as the brain directs them to create movement. (6, 25)

Motor control-stability (stability motor control or neuromotor stability): The ability of the brain to regulate muscle activity (co-contraction of opposing muscle groups) to keep joints or body segments from moving at times when they should not move, as in providing stability at a joint. (6, 24)

Motor coordination: A specific subset of motor control-movement that specifically focuses on the motor control interactions and cooperation between opposing muscle groups during a movement. (6)

Motor development: The progressive acquisition of movement and motor skills associated with maturation, especially early in the lifespan. (24)

Motor distal latency: In a motor conduction study, the latency obtained by stimulating the motor nerve at the most distal site. (12)

Motor function: Normal expressions of the motor system including motor control and motor learning. (6)

Motor learning: The process of acquiring a new motor skill or motor behavior, usually involving practice with repetitions and feedback. (24)

Motor level: The most caudal neurological segment of the spinal cord with normal motor function on both sides of the body. Normal motor function is considered to be at least 3/5 strength in specific key muscles associated with each myotome. (26)

Motor (output) system: A system composed of the vestibular ocular reflex (VOR) and vestibular spinal reflex (VSR) that produce compensatory movements to control gaze stability (ability to fixate on targets) and posture. (8)

Motor Relearning Program (MRP): An eclectic model for examination and interventions combining concepts from the hierarchical model with current information on kinesiology, kinematics, and task oriented approaches. The term was coined by Carr and Shephard. (15)

Motor unit (MU): An alpha motor neuron and all the muscle fibers innervated by the neuron. (22)

Movement control: [See Motor control for movement (MC-movement).] (6)

Movement sense: The awareness of the degree, velocity, and direction of movement at a single joint or body segment. (5)

Movement time: The time between initiation and completion of a movement task. (25)

Multidimensional measures: Tools that measure a range of functional domains using one published tool; may include activities such as upper extremity function, lower extremity function, bed mobility, and gait. (10)

Multidirectional reach test: A test of balance which tests the subject reaching forward like the Functional Reach Test, but also tests the magnitude of reach in backward and lateral (right and left) directions. [See Functional Reach Test.] (9)

Muscle contracture: Contracture that is specifically due to shortened muscle. (23)

Muscle cramp: A sustained involuntary muscle contraction. (12)

Muscle endurance: The capacity of a muscle to sustain work and resist fatigue-related decrements of muscle performance. (6, 22)

Muscle fatigue: A decline in muscle performance that results from prolonged or sustained use of the target muscle group, and may or may not in general occur during or after physical exertion. (6, 22)

Muscle flexibility: The length and extensibility of musculotendi-nous structures that cross a particular joint and their influence on the ability of the joint to move. (6)

Muscle hypertrophy: Increased muscle size due to an increase in the number and size of myofibrils. (22)

Muscle performance: Normal expressions of a muscle including aspects of muscle strength or force generation, power, endurance, and length or extensibility. (6)

Muscle power: The rate at which work is performed (work/time or force velocity). (22)

Muscle spindle: A proprioceptive sensory receptor located within a muscle that provides information about changes in muscle length. (27)

Muscle strength: The ability of a muscle to generate force to cause movement. (6)

Muscle substitution: Using a muscle to compensate for other muscles that are weak or nonfunctional. (26)

Muscle tone: The amount of inherent neuromuscular activity present even in a resting muscle and is detected by the response, specifically the amount of resistance, to passive elongation or stretch of the muscle being tested. (6, 18)

Mydriasis: An abnormally dilated pupil as occurs with cranial nerve (CN) III palsy. (7)

Myelopathic pain: Central pain due to spinal cord damage that may involve nerve root damage. (28)

Myocardial contractility: Innate contractile state of the heart. (11)

Myoclonus: Characterized by brief, sudden, and rapid asymmetrical contractions involving a group of muscles. Movements are nonrhythmic and can be focal, unilateral, or bilateral. (20)

Myokymic discharges: Grouped, spontaneous, repetitive discharges of the same motor unit, occurring in bursts, representing groups of involuntary fasciculations. (12)

Myopia: Visual deficit in which a person cannot see things clearly at a distance, sometimes referred to as "near-sighted." (7)

Myosin heavy chain isoforms: Different forms of functionally similar motor proteins that are constituents of mammalian skeletal muscle fibers. (32)

Myotome: Muscles or muscle groups innervated by a single spinal root that usually perform similar actions. (6)

Myotonic discharge: In electromyographic (EMG) studies, the spontaneous discharge of a muscle fiber (similar to a fibrillation or positive sharp wave) that waxes and wanes in both amplitude and frequency, characteristically seen in myotonic disorders. (12)

Natural environment: The location for delivery of family-centered care in pediatrics; the usual, or typical, environment of the child and family. (24)

Needle electromyography (needle EMG): A test of the electrical activity of muscles using a needle electrode. (12)

Negative neurological signs: Signs or test results that represent a loss or decrease in system function. (6)

Negative signs/symptoms: Signs/symptoms characterized by a reduction or loss of normal activity coming from the central nervous system. (25)

Neglect: Impaired ability to orient, identify, or respond to stimuli located opposite of the site of a brain lesion (e.g., right-sided brain lesion resulting in left-sided neglect). (18, 31)

Neonate: An infant less than 1 month old. (12)

Nerve conduction studies (NCS): Electrophysiologic testing that assesses the function of motor and sensory nerves. (12)

Neural factor: Contributions to passive stiffness resulting from the effects of a central nervous system lesion, specifically from stretch reflex hyperactivity and hypertonia (i.e., spasticity or reflex stiffness). (23)

Neural plasticity: The adaptive capacity of the central nervous system to remodel and form new connections in response to environmental diversity and purposeful repetition. (1, 25, 37)

Neuralgia: Pain that occurs along the course of a nerve. (28)

Neurapraxia: The mildest form of traumatic injury to a peripheral nerve, in which the nerve is demyelinated while the axon remains intact. (26)

Neurodevelopmental Treatment (NDT): Treatment approach developed by Karl and Berta Bobath to emphasize individual-ized therapeutic handling based on movement analysis and to promote normal movement patterns after a central nervous system insult. (15)

Neurofacilitation approaches: Methods of interventions based on reflex and hierarchical models. Interventions are based on sensory cues to inhibit hypertonicity and abnormal synergy patterns and to facilitate normal movement. (15)

Neurological level of injury: The most caudal neurological segment of the spinal cord with normal sensory and motor function on both sides of the body. (26)

Neurological recovery (or neurological return): Recovery of motor or sensory function below the neurological level of the injury. (26)

Neuro-maturational theory: A developmental theory promoted by Gesell that emphasizes the predictable and orderly appearance of infant/child behavior as the nervous system matures. (13)

Neuromotor development: The process of change in motor behavior that is related to the age of the individual. (13)

Neuromotor stability: A synonym for motor control-stability. (24)

Neuromuscular electrical stimulation (NMES): Electrical current applied to weak muscles to elicit muscle activation; used to increase muscle strength, facilitate motor control (muscle reeducation), and/or prevent disuse atrophy. (18, 19, 22, 24, 25)

Neuromyotonia: In electromyographic studies, muscle activity that is more widespread and continuous than muscle cramps, characterized by repetitive firing of a single motor unit at high frequency (150–350 Hz) that wanes before it stops. (12)

Neuropathic pain (neurogenic pain): Pain that arises from damage to the nervous system (peripheral or central), characterized by localization to specific dermatomes or nerve distributions. (28)

Neuropathy: A general term referring to any disease or dysfunction of a peripheral nerve or nerves. [See mononeuropathy and polyneuropathy.] (28)

Neuroprosthesis: A device that uses electrodes to interface with the nervous system and substitute or supplement motor or sensory function after neurologic impairment (e.g., facilitate appropriately timed lower extremity dorsiflexion during gait in an individual who has had a stroke). (18)

Neurotmesis: The most severe form of peripheral nerve injury in which the axon is severed and the connective tissue coverings are disrupted. (26)

Neutral warmth: Wrapping of body or limb in blanket or towel for purpose of general relaxation. (15)

Nociception: A type of sensation in which a stimulus activates peripheral nerve fibers that carry pain (e.g., C fibers, A-TM fibers), with the resulting transmission of impulses along peripheral nerves to the central nervous system, where the afferent input is perceived as pain. (28)

Nociceptors: Free nerve endings that serve as pain receptors by detecting painful stimuli. (28)

Nominal scale: Classifies options in mutually exclusive categories such as male or female. (10)

Nonblood body fluid: Laboratory measures that analyze nonvas-cular organ and body cavity fluids for the identification of cellular components, infectious microorganisms, antibodies, and quantify certain chemistry analytes. (12)

Nonconjugate eye movements: Abnormality in which the two eyes do not move together in either the same direction, or with identical speed or magnitude. (7)

Noncontractile: The components of a joint, such as the ligaments, bone, and joint capsule, that are not capable of generating a force and are not directly connected with muscle tissue. (23)

Nondeclarative or implicit memory: Recall that does not require conscious awareness of components of the task; seen in more automatic responses. [See implicit memory for synonym; declarative memory or explicit memory for contrast.] (4)

Nonfatiguing exercise: Exercise that involves short intervals of low- to moderate-intensity (five to 10 repetitions) with frequent rests in between to recover. (22)

Nonfluent aphasia: Communication impairment character-ized by a hesitant interruptive flow of speech with limited vocabulary. (4)

Nonneural factors: Contributions to passive stiffness from changes of intrinsic muscular properties and connective tissue due to immobilization or aging. These biomechanical changes can occur in both contractile and noncontractile structures. (23)

Non–patient-identified problems (NPIPs): Problems not identified by the patient that may be current problems or problems that may occur in the future. (2)

Nonregulatory environmental feature: An environmental condition that has the potential to affect movement but may not necessarily change the movement. In stand-to-sit, for example, the lighting in the room can affect the movement but does not necessarily lead to a change in movement pattern. Other nonregulatory features include the temperature of the room or the color of the chair. (36)

Nonvestibular deficit: Disorder of balance that is not related to vestibular pathology. (29)

Norm-referenced: A standardized test given to a large representative sample of individuals so a particular individual's score can be compared with the average scores of the sample. (13)

Normal reference range: The normal reference range is a set of values used to interpret clinical laboratory test results and is usually defined as the set of values within two standard deviations of the mean value of a normal population, which represents approximately 95% of the normal population. (12)

Normative belief: The belief about whether each of the individual's referents approves or disapproves of a given behavior; along with motivation to comply, it determines the individual's subjective norm in the Theory of Planned Behavior. (16)

Normogenic: Considering a framework for delivery of health care services, a normogenic orientation would seek to maintain the normal state of health (Bezner, 2007). [See salutogenic and pathogenic as contrasting orientations.] (16)

Novice clinician: An individual with little experience in the field or practice. (1)

Nuclear medicine: Diagnostic imaging studies that combine imaging with administration of some radioactive substance to allow visualization of physiological processes. (12)

Nystagmus: An involuntary, rapid, rhythmical movement of the eyeball which may be horizontal, vertical, rotator, or a combination of movement directions, often as an indication of vestibular or cerebellar dysfunction. (8, 21, 29)

Objective: A statement of expected achievement that specifies: (1) who will perform the behavior, (2) what the specific behavior is, (3) under what conditions the behavior will be performed, and (4) how the outcome will be measured. Reflects a limited time span, generally greater than 3 weeks and frequently termed the short-term goal (STG). (2)

Objective measures: Measurements of a task or aspects of a task that are actual instrumental readings or counts that are repeatable and more likely to be free of bias. (1, 10)

Observational analysis: The process of observing the performance of a specific task and recording the results; examination that includes both observational analysis and subjective analysis. (10)

Observational gait analysis (OGA): Process of observing a person walking and documenting deficits compared with normal. (10)

Observational practice: Practice that occurs when a person observes another person's movement. The observer is asked to pay attention to certain features of the movement or critique the movement. (36)

Obtunded: The state of being difficult to arouse from sleep, requiring repeated stimulation. (4)

Occupational therapists: Licensed health professionals who provide rehabilitation interventions to support participation, performance, and function in roles and situations in home, school, workplace, community, and other settings (AOTA, 2015). (1)

Occupations: All aspects that "occupy" a person's time and life, not just a job or employment; includes activities of daily living, instrumental activities of daily living, education, work, play, leisure activities, and social participation. (33)

Ocular dysmetria: An error in ocular fixation consisting of overshooting the desired focus followed by oscillations of focus until focus is achieved. (21)

Ocular movements: Motion of the eyes. (8)

Oculomotor nerve: Cranial nerve III that innervates the levator palpebrae for eyelid opening, and extraocular muscles superior rectus, medial rectus, inferior rectus, and inferior oblique as well as proprioception to these same muscles. (7)

Olfaction: The special sense of smell. (7)

Olfactory nerve: Cranial nerve I that carries the special sense of smell. (7)

Open chain exercise: A non–weight-bearing position is assumed, and the distal segment moves freely in space against resistance. (22)

Open loop system: Type of movement control used when the body must prepare before the execution of a voluntary movement. As such, the central nervous system cannot rely on feedback and must rely instead on past experiences to best perform a movement task. (25)

Open movement task: Task performed in a constantly changing environment. (25)

Optic chiasm: A connection between the optic nerves from each side that allows for decussation of the optic nerve fibers from the medial half of each retina (detects the lateral half of each visual field). (7)

Optic nerve: Cranial nerve II that carries the special sense of vision. (7)

Optic tract: The portion of cranial nerve II that extends from the optic chiasm posteriorly into the substance of the brain as it moves toward the lateral geniculate bodies. (7)

Optokinetic test: Performed as part of the rotary chair test to measure the nystagmus produced while a patient is viewing a moving, striped optical drum. (8)

Ordinal scale: Ordered, ranked categories without equal spacing between numerical values such as values for level of assistance during transfers. (10)

Organ of Corti: The special organ of the inner ear that houses the receptor cells for hearing. (7)

Organization: The spatial and temporal relationship between the component parts of a skill. Highly organized skills are spatially and temporally interdependent. (37)

Orthodromic: In sensory nerve conduction testing, stimulating distally while recording proximally. (12)

Orthosis: An external supportive and/or assistive device interfaced externally to the human body for the treatment of neuro-muscular and/or musculoskeletal deficits secondary to disease, trauma, or a congenital disorder involving the arms, legs, and/or spine. The term "brace" is a synonym. (17)

Orthostatic hypotension: Drop in blood pressure when a person changes position. Typically when moving to standing position. (11)

Oscillopsia: A false illusion of movement of the environment or objects in the environment. (8, 29)

Osteotomy: Surgical excision of bone in order to reduce a deformity and increase function. (19)

Otoconia: Calcium carbonate crystals that comprise the lining of the utricles and saccule. (8, 29)

Otolith counterrolling: The reflexive, conjugate movement of the eyes rotating opposite to the direction of head tilt. (29)

Otolith: The part of the vestibular apparatus of the inner ear composed of the utricle and saccule that senses linear acceleration of the head. (8, 29)

Outcome expectations: In Social Cognitive Theory, the individual's belief that performing the target behavior will lead to the desired outcome. (16)

Outcome measure: Tools and methods used to assist in determining the effectiveness of treatment or treatment approach; overall result of care. (1, 10)

Outcomes: The anticipated level of functioning at the end of the episode of care, resulting from remediation of functional limitations, prevention of disability, and optimization of health status and patient satisfaction. (2)

Overcompensation: A specific component of ataxia; in attempting to correct a dysmetric, ataxic error (over- or undershooting), the individual overcorrects and again passes the target. (6)

Overflow: The spread of muscle activation from stronger muscles to weaker muscles within a synergistic pattern. [See irradiation.] (15, 18)

Overload: Principle in which a muscle needs to be progressively challenged beyond its current force capability in order to promote neuromuscular adaptation to produce gains in strength-generating capability. (22)

Overwork weakness: "A prolonged decrease in absolute strength and endurance of a muscle due to excessive activity" (Bassile, 1996). (22)

Oxygen consumption (VO₂): The rate at which oxygen is used by tissues; an index of the body's efficiency at producing work; expressed in milliliters of oxygen consumed per minute. (11, 32)

Oxygen delivery: Extraction of oxygen from the blood by body tissues. (11)

Oxygen transport: The process of taking oxygen into the body from air and delivering it to body tissues. (11)

Pacing skills training: A type of behavioral skills training in which the individual is taught to break up large tasks into smaller, more manageable components that do not induce a pain flare-up. (28)

Pain: As defined by the International Association for the Study of Pain (1994), an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage. (28)

Pain behavior: Objective (i.e., behavioral) indicators that an individual is experiencing pain, including both verbal and nonverbal behaviors. (28)

Pain cognitions: Psychological constructs related to the experience and expression of pain; examples include self-efficacy, catastrophizing, fear of movement, and perceived control over pain. (28)

Pain sensibility: Awareness of unpleasant sensation when the stimulus has the potential to cause tissue damage. (5)

Paradoxical breathing: A pattern of breathing, from diaphragm and/or intercostal paralysis, in which the upper chest collapses and the abdomen rises excessively during inspiration. (11)

Paralysis: A complete loss of ability to move a specified muscle group; a complete absence of the ability to generate force in a muscle. (6)

Paraphasia: Word substitution error made while speaking that may or may not be similar to its target (e.g., patient says "fork" or "pencil" instead of "knife"). (31)

Paraplegia: Impairment or loss of motor and/or sensory function in the thoracic, lumbar, or sacral (but not cervical) segment of the spinal cord with paralysis of lower extremities below the lesion but preservation of upper extremity function and the trunk above the lesion level. (11, 26)

Paraplegic distribution: A pattern in which symptoms occur only in the bilateral lower extremities or lower extremities and trunk, often associated with spinal cord injury. (5)

Parasympathetic nervous system: The part of the autonomic nervous system, arising through cranial nerves and sacral spinal levels, and operating counter to the sympathetic nervous system; includes decreased heart rate, vasodilation, and enhanced digestive processes. (7)

Paresis: A form of motor impairment including weakness or partial paralysis. (6)

Paresthesia: An abnormal, negatively perceived sensation that results from injury to one or more nerves and may include numbness, stinging, or burning. (5, 27, 28)

Participation: A term in the International Classification of Functioning, Disability and Health (ICF) model to describe an individual's involvement in society, including the ability to fulfill life roles and experience life situations; also enhanced by the absence of handicap. (1)

Participation restrictions: Problems an individual may experience in involvement in life situations. (3)

Part-task training: The practice of component parts of task. For example, during gait training the patient will be asked to practice lateral weight shifts for several repetitions, followed by taking one step forward and back with one lower extremity for several repetitions. The part-task training is typically followed with whole-task training during the same intervention session. (15)

Passive insufficiency: In two-joint muscles, the inability to achieve full range of motion at both joints when the muscle is put on stretch (moved into the antagonistic direction). (6)

Passive range of motion (PROM): The motion at a joint that can occur when an external force is applied with the patient fully relaxed. (6, 23)

Pathogenic: Considering a framework for delivery of health-care services, a pathogenic orientation is based on remediating the underlying pathology or cause of disease (Bezner, 2007). [See normogenic and salutogenic orientations in contrast.] (16)

Pathology: Term from Nagi and the National Center for Medical Rehabilitation Research (NCMRR) to describe abnormal expression that occurs at the cell, tissue, or organ level. (1)

Patients: In the Guide to Physical Therapist Practice (APTA, 2003), individuals who are receiving clinical services. (1, 16)

Patient education: Information and instruction provided to patients to optimize their rehabilitation and health status through helping them understand their disease process and emphasizing the essential nature of their personal involvement in the rehabilitation process, including changes in daily behav-ior and home exercises/activities. (1)

Patient management: The ongoing process associated with administering (development and adjustment of) the patient's plan of care. (2)

Patient-centered focus: Also called client-centered care, a focus on patient care that is individualized for the particular patient and emphasizes the patient's and/or family's goals and values. (1)

Patient-identified problems (PIPs): Problems that the patient identifies; usually functional limitations and disabilities. (2)

Peak oxygen consumption (VO₂peak): The highest oxygen intake that an individual can attain during physical work without achieving a "plateau." [See maximal oxygen consumption.] (32)

Pediatric reach test: A pediatric version of the Multidirectional Reach Test. [See Multidimensional Reach Test.] (9)

People-first language: A guideline calling for health-care professionals to "put people first, not their disability, when communicating about a patient/client" (APTA, 1991). (1)

Perceived behavioral control: The factor in the Theory of Planned Behavior that, along with attitude toward the behavior and subjective norm, determines the individual's behavioral intention with respect to a target health behavior. (16)

Perceived power: The perceived effect of each facilitating or constraining condition in making performance of the target behavior difficult or easy; along with control belief, it determines the individual's perceived behavioral control in the Theory of Planned Behavior. (16)

Percentile score: In standardized, norm-referenced testing, the number of individuals of the same age who would be expected to score lower than the individual tested. (13)

Perception: The cerebral process that results in a composite experience and understanding of sensory information; includes selecting, processing, organizing, and integrating information received from the senses. (4, 13, 27)

Perceptual ability: Processing of sensory information (e.g., height of step) to function safely in daily living. (31)

Performance-based examination: Process in which the therapist observes the patient performing a specific task. (10)

Peripheral distribution: A pattern in which symptoms occur generally in the most distal parts of the limb. (5)

Peripheral nerve distribution: A pattern in which symptoms are characteristic of the sensory distribution or specific motor components of a particular cutaneous nerve or peripheral nerve. (5)

Peripheral vestibular system: A system composed of three semicircular canals (anterior, posterior, and lateral/horizontal) and two otolith organs (utricle and saccule) that detect angular and linear acceleration, respectively. (8, 29)

Periventricular leukomalacia (PVL): Pathology of the subcortical white-matter particularly adjacent to the lateral ventricles, especially in premature infants, characterized by necrosis with scarring and cysts, and indicating increased risk for development of cerebral palsy. (12)

Persistent postural-perceptional dizziness: A disorder that involves persistent postural dizziness without rotational vertigo that is worse with upright postures and exacerbated by busy environments, illness, or stress. (29)

Phasic muscles: Muscles located more superficially, laterally, and distally in the body; primarily used in voluntary movement of short duration. (15)

Phenotype: The expression of a specific trait based on genetic and environmental influences. (32)

Physical activity: Bodily movement produced by skeletal muscle contraction, which substantially increases energy expenditure above resting levels. (32)

Physical deconditioning: A decline in fitness and strength that can result from physical inactivity. (11)

Physical fitness: "(A) dynamic physical state—comprising cardiovascular/pulmonary endurance; muscle strength, power, endurance and flexibility; relaxation; and body composition— that allows optimal and efficient performance of daily and leisure activities" (APTA, 2003). (16)

Physical rehabilitation: The multidisciplinary treatment process for individuals with physical disabilities to restore the individual to optimal life and capacity, including therapeutic intervention procedures and education. (1)

Physical therapists: Highly educated, licensed health-care professionals who can help patients reduce pain and improve or restore mobility—in many cases without expensive surgery and often reducing the need for long-term use of prescription medications and their side effects (APTA, 2011). (1)

Physical therapy diagnosis: A label that clearly specifies the movement-related problem for which the therapist will provide intervention. (1)

Pincer grip: Grip of a small object between the distal pads of the opposed thumb and index or middle finger. (6)

Pitch: Movement of the head in the sagittal plane to turn the head up-and-down about the x-axis. (29)

Plan of care (POC): The delineation of the physical therapy diagnosis, prognosis, treatment goals and outcomes, planned interventions, and discharge criteria. (2)

Pneumonia: Inflammation of the lung usually the result of bacterial or viral infection; alveoli may fill with fluid and/or pus. (11)

Peripheral neuromuscular facilitation (PNF) chop: A bilateral asymmetrical PNF pattern with the lead arm performing the D1 extension pattern and the other arm performing the D2 extension. The chop emphasizes upper trunk flexion and rotation. (35)

Peripheral neuromuscular facilitation (PNF) lift: An upper trunk PNF pattern combining bilateral asymmetrical flexion patterns of the upper extremities, with the lead arm completing the D2 flexion pattern and the assisting arm grasping the wrist of the lead arm, thereby completing a modified D1 flexion pattern. The lift emphasizes upper trunk extension and rotation. (35)

Peripheral neuromuscular facilitation (PNF) reverse chop: The reverse of the PNF chop with a bilateral asymmetrical pattern, with the lead arm performing the D1 flexion pattern and the other arm performing D2 flexion. (35)

Peripheral neuromuscular facilitation (PNF) reverse lift: The reverse of the PNF lift with a bilateral asymmetrical PNF pattern, with the lead arm performing the D2 extension pattern and the other arm performing D1 extension. (35)

Polyneuropathy: A subtype of neuropathy with disease or dysfunction of multiple nerves. (26, 28)

Polyphasia: A measure of synchrony of the muscle fibers firing within a motor unit. (12)

Position sense: The awareness of static positions of a single joint or body segment detected without the use of vision. (5)

Positional test: Performed as part of electronystagmography (ENG) or videonystagmography (VNG) to measure nystagmus associated with positions of the head. (8)

Positive neurological signs: Signs or test results that are not present in a normal individual, but appear or develop following neurological disorders. (6)

Positive sharp waves: In electromyographic (EMG) studies, a biphasic positive-negative potential recorded from a single muscle fiber at rest. (12)

Positive signs/symptoms: An increase in abnormal behaviors that can typically be controlled or inhibited by the central nervous system. (25)

Positron Emission Tomography (PET): An imaging method that utilizes the emission of photons, or energy packets, from within the patient. (12)

Post-traumatic amnesia (PTA): The loss of memory regarding events pre/post brain injury as well as a loss of ability to process information following brain injury. (4)

Postural control or stability: The ability to maintain equilibrium and upright orientation in a gravitational environment. (9, 30)

Postural tone: The state of muscular tension in the body as a whole. (18)

Postural tremor: A pathological tremor, typically 3-5Hz, in a limb or the trunk when either is working against forces of gravity. (21)

Posturography: Computerized balance assessment of posture and weight distribution with objective data collected from a force platform. (9)

Power grasp: The prehension grasp involving the ulnar side of the hand, particularly the third, fourth, and fifth digits, and the ulnar side of the palm when power is required for heavy objects or heavy work. (33)

Precision grasp: The prehension grasp to manipulate small objects, involving the radial side of the hand, especially the pads of the thumb and index finger. (33)

Precontemplation: Stage in the Transtheoretical Model (Stages of Change) in which the person has no intention to take action within the next 6 months. (16)

Prediabetes: A condition in which some but not all of the diagnostic criteria for diabetes are present; impaired fasting glucose level or impaired glucose tolerance. (32)

Prehensile movement or prehension: The finger action of taking or clasping objects, including precision grasps and power grasps. (33)

Premature ventricular contractions (PVCs): Cardiac arrhythmia where the ventricular complex occurs earlier than expected. It is characterized on the electrocardiogram (ECG) by a wide bizarre QRS complex occurring without a P wave preceding it. PVCs can be benign in healthy individuals but in the presence of cardiac disease can be indicative of ischemia or can precede a more lethal rhythm (e.g., ventricular tachycardia or ventricular fibrillation). (11)

Premorbid: Occurring before the onset of a disease or disorder. (32)

Preparation: Stage in the Transtheoretical Model (Stages of Change) in which the person intends to take action within the next 30 days. (16)

Preparatory breaking: The initial phase of termination of gait characterized by the initial (<10%) reduction in gait velocity. (37)

Presbyopia: Decreased ability to focus visually on near objects; also called farsightedness. (33)

Presence: Degree of immersion in the virtual world during virtual reality. (25)

Pressure garments: Articles of clothing, typically made of highly elastic materials, which can be used as external supports for joint/segment stability and proprioceptive input. (24)

Pressure touch: Sensation that results from mechanical stimulation of skin with skin deformation. (5)

Primary aging: Changes associated with increasing age that are largely unavoidable and are due to an individual's genetic predisposition to bodily deterioration over a lifetime. (37)

Primary impairment: Organ or system dysfunction that results directly from a pathology. (1, 25)

Primary prevention: "Prevention of disease in a susceptible or potentially susceptible population through specific measures such as general health promotion efforts" (APTA, 2003, p. 24). (16)

Primary progressive multiple sclerosis (MS): A form of MS in which neurological symptoms slowly progress over time with periods of stability rather than actual remission. (25)

Primary visual cortex: The cortex that receives the visual sensory input, anatomically located in the medial occipital lobe. (7)

Primitive reflex, or more specifically, the asymmetrical tonic neck reflex: In which rotation of the neck to one side results in automatic extension of the arm and leg on the face side and flexion of the arm and leg on the back side of the head; it is typically observed from birth until about 4 to 6 months of age. (15)

Problem list: A list of the patient's functional limitations/ participation restrictions. (3)

Problem-solving: Modification of tasks, utilization of accommodations, mobilization of social supports, and restructuring of the environment in ways that allow household chores or work tasks to be accomplished without inducing a pain flare-up. (28)

Procedural interventions: The actual procedures and techniques used by a therapist to execute a plan of care and bring about change in the patient. (2)

Procedural memory: Ability to remember through routines or habits, including motor memories (e.g., remembering how to tie a pair of shoes). [See implicit memory.] (4, 31)

Prognosis: The predicted optimal level of improvement in function and the amount of time needed to reach that level based on diagnosis and individual factors. (1, 2)

Progressive neuromuscular disorders: Diseases that have a progressive worsening of impairments and a progressive decline in activity as part of the expected course of the disease. (1)

Progressive resistive exercise (PRE): A resistive load systematically applied and progressed during training as prescribed by a specific percentage of the muscle's maximal capability. (22)

Prolonged stretch: Application of slow passive lengthening of a muscle inhibits its contraction. (15)

Proprioception: A general category of sensation involving awareness of both position and movement in relation to the body. (5, 27)

Proprioceptive neuromuscular facilitation (PNF): Treatment approach developed by Kabat, Knott, and Voss using developmental sequence patterns and facilitation techniques, such as quick stretch and manual resistance, that are useful to improve motor recruitment, timing, and coordinated activation of functional motor patterns. (15, 22)

Prospective memory: Ability to remember an intended action in the future. (31)

Protective extension: An automatic reaction that involves extension or abduction of the arm or leg to widen the base of support, protect from injury, and prevent falling, particularly in situations where balance reactions are failing. (30, 35)

Protective reactions: Automatic neural reactions that prevent a fall after the center of mass moves irreparably beyond the limits of stability, and prevent injury by one or more extremities reaching out to prop on the surface, or reset/expand the base of support in the direction of the disturbance to avert a fall. (9, 13)

Pseudostrabismus: The position of the two eyes do not appear to be aligned, but the reflection of room lights are similarly placed on each cornea. (7)

Psychometric properties: Specific characteristics of standardized measures including reliability, validity, and predictive values. (10)

Ptosis: The eyelids sag on the affected side with inability to raise the eyelid; related to cranial nerve III deficit. (7)

Pull-to-sit maneuver: With an infant supine on the floor (feet nearest to the examiner), the infant's hands are grasped and the infant is gently pulled into a sitting position. (18, 35)

Pulmonary ventilation: Mechanical process of moving air into and out of the lungs; inhaling and exhaling. (11)

Pulse oximetry: A measure obtained using specialized instrumentation that estimates oxygen saturation of circulating hemoglobin using a surface sensor. (11)

Pulse-oximeter: A piece of equipment that uses noninvasive means (no blood drawn) to measure the oxygen saturation of circulating hemoglobin. (12)

Pusher syndrome or lateral retropulsion: A syndrome that can be associated with hemiplegia and perceptual dysfunction and is observed in standing as a strong extensor activity of the nonaffected lower limb, with hemineglect of the affected side, resulting in severe postural imbalance. (30)

Quadriplegia: [See tetraplegia.] (11)

Quadruped position: Sometimes called the "hands and knees" position or "all fours," this functional position involves four-point weight-bearing through both hands and both knees; the position used for creeping. (15, 24)

Quality of life: A psychological construct related to an individual's overall sense of purpose and well-being. (28)

Quick (fast) brushing: High frequency brushing that provides sensory input to C fibers of the skin overlying a muscle resulting in stimulating muscle activation or recruitment. (15)

Quick icing: Applying ice in short quick strokes on the skin overlying a muscle to provide sensory stimulation to A fibers stimulating muscle activation or recruitment. (18)

Quick stretch: A gentle quick stretch applied to a muscle in its lengthened position stimulating 1a afferents of the muscle spindle resulting in a contraction of that same muscle. (15, 18)

Quick tapping: Quick manual tapping to a tendon or muscle giving a quick stretch to a muscle that stimulates muscle activation or recruitment. [See quick stretch.] (18)

Radiculopathy: A general term referring to any disease of a nerve root. (28)

Radiographs: An image produced by exposing a body segment to diagnostic level radiation and recording the image on film. (12)

Rag doll posture: In a prone suspended position, the infant's body forms an inverted "U," evidenced by a lack of motor control in neck/trunk extensors and the inability to lift against gravity. (18)

Range of motion: The ability of a joint to be moved passively or actively and the extent of motion available. (6)

Rate-pressure product: The product of systolic blood pressure multiplied by heart rate. (32)

Rating of perceived exertion (RPE): A proxy measure of exercise intensity that uses a numerical scale to quantify a subjective level of effort while exercising. (32)

Ratio scale: Equal intervals between categories and a true zero point; may be added and subtracted and may be used in statistical operations. (10)

Reach: The actions beginning with torso orientation to a desired object and including the shoulder, arm, and hand motions required to obtain an object distant from the body. (33)

Reaction time: The time between when an individual decides to move and when the intended movement begins. (25)

Reasoning: The ability to think, understand, and formulate judgments based on all available information; one aspect of normal cognition. (4)

Rebound phenomenon: The inability of the neural system, particularly due to the loss of the exquisite ability of the cerebellum to detect position and movement in a particular muscle, to stop any movement when an isometric contraction against any joint movement is suddenly terminated. (21)

Rebound test: A test in which isometric tension is built-up in a muscle group, and then is suddenly released. (6)

Recent memory: Ability to recall (remember) after a period of interference. (31)

Receptive aphasia: Difficulty understanding language. (31)

Reciprocal inhibition: Contraction of the agonist results in relaxation of the antagonist, mediated through an inhibitory interneu-ron to the alpha motor neuron of the antagonist. (15)

Reconceptualization: The process of actively challenging and changing cognitive distortions or irrational beliefs in people with pain (e.g., all-or-none thinking, selective perception, catastrophizing) to improve coping and quality of life. (28)

Reconstruction: In computerized tomography (CT), the process of turning raw scanned data into image or slice. [See computerized tomography.] (12)

Reference limb: During gait, the lower extremity observed and analyzed. (10)

Reference ranges: The array of values that represent a normal population, established independently by individual clinical laboratories through an analysis of a minimum of 100 specimens from a healthy local population. (12)

Referent: In the Theory of Planned Behavior, a significant other—someone of importance to the individual. (16)

Referred pain: Pain that is perceived at a site distant from the source of the pain. (5)

Reflective practice: "Those intellectual and affective activities in which individuals engage to explore their own experience in order to lead to new understandings and appreciations" (Gould, 1994). (1)

Reflex: An automatic action that is performed as a response to a stimulus and without conscious thought. (13, 23)

Reflex stiffness: An alternative term for spasticity or neural factors leading to increased passive stiffness. (23)

Reflex sympathetic dystrophy: [See complex regional pain syndrome.] (28)

Rehabilitation engineer: A classification of personnel by Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) describing a professional who uses specialized knowledge or skills to design, build, and maintain complicated equipment, systems, processes, etc., for individuals with disabilities (www.RESNA.org). (17)

Relapsing-remitting multiple sclerosis (MS): The most common form of MS, remarkable for periods of neurological loss followed by remission of symptoms. Time between phases varies greatly. (25)

Relative phase relationship: A consistent association between related parts (e.g., during the gait cycle, an out-of-phase relationship that is demonstrated as swing phase in one leg is always associated with stance phase in the opposite leg). (37)

Relaxation training: A self-management strategy employed to reduce muscle tension that is likely to aggravate pain and to increase an individual's awareness of the importance of taking breaks, rather than spending all of his time meeting others' needs and demands. (28)

Reliability: Consistency of repeated measurements; scores should be consistent over time for one examiner (intrarater reliability) and consistent between examiners (interrater reliability). (3, 13)

Remediation approach: A rehabilitation approach in which tasks are retrained using normal biomechanics/strategies; may include the reduction of impairments that interfere with the task or strategy. (36)

Remembered targets: An exercise in which the patient focuses on a target, then closes the eyes and turns the head while attempting to maintain focus on an imaginary target. (29)

Remote memory: Inability to recall a memory from the distant past. (31)

Repeated contractions: A peripheral neuromuscular facilitation (PNF) technique that includes isometric contractions of the target muscle group during a specific midrange movement pattern or at the end of a specific range. (15)

Repeated quick stretch: A peripheral neuromuscular facilitation (PNF) technique with repetitive application of "quick stretch" throughout the active range to facilitate the stretched muscle for greater contraction/strength, coordination, control, or to increase active range of motion. (15)

Repetitive motor nerve stimulation (RMNS): Electrophysio-logic testing performed by stimulating a peripheral motor nerve. (12)

Respiratory exchange ratio (RER): The ratio of the amount of carbon dioxide produced by the body to the amount of oxygen consumed. (32)

Respiratory insufficiency: Inadequate gas exchange by the respiratory system resulting in reduced ability to maintain arterial oxygen and/or carbon dioxide level within the normal range. (32)

Respiratory rate (RR): The number of respiratory cycles (inhalation plus exhalation) during a minute. (11, 32)

Rest interval: A period of time between sets of exercise to allow muscle energy sources to be restored. (22)

Retinal slip: Movement of a visual image on the retina during head movement. (29)

Retrograde amnesia: Loss of memory related to events prior to a brain injury. (4)

Reversibility: The potential detraining effects that can occur unless strength is maintained. (22)

Rhythmic initiation: A peripheral neuromuscular facilitation (PNF) technique that progresses movement of the agonists from passive to active-assistive, to active-resistive, as able; often used when a patient demonstrates difficulty initiating movement. (15, 19, 34)

Rhythmic rotation: Applying slow low-amplitude rhythmic rotary movement to the body or head to result in general muscular relaxation and decreased tone. (19)

Rhythmic stabilization (RS): Simultaneous isometric contractions of all muscles, in all three planes, around a joint. The therapist's manual contacts are on opposite sides of the joint, resistance is given simultaneously in both directions. Often a verbal cue of "don't let me twist you" is given. Technique is used with individuals who have difficulty holding or maintaining a position, increasing stability in weight-bearing. (15, 24, 34, 35)

Righting reactions: Automatic neural reactions that orient the head in space and the body in relation to the head and support surface and can occur in response to visual (optical righting), vestibular (labyrinthine righting), or somatosensory (body on head righting) cues. When the body is tilted in any direction within the base of support, the head automatically rights itself so the head is vertical and mouth is horizontal with reference to the ground. When the weight shift is large enough to extend outside the base of support, the trunk laterally bends toward upright and with larger excursions, the arm and leg will also abduct to maintain balance. (9, 13, 18, 35)

Right-left discrimination: The ability to discriminate the left and right side of the body. (4)

Rigidity (rigid hypertonia): A form of hypertonicity, in which the increased resistance to passive elongation is not velocity dependent, is detected throughout the available range of motion, and usually is present in both agonist and antagonist muscle groups (difficult to extend and difficult to flex). (6, 19)

Rinne test: A hearing test that compares the perception of sounds transmitted by air conduction to those transmitted by bone conduction through the mastoid. (7)

Risk assessment: According to Slikker and Gaylor (1995), "an empirically-based process used to determine the probability that adverse or abnormal effects are associated with exposure to a chemical, physical or biological agent." (16)

Risk factor: "An environmental, chemical, psychological, physiological, or genetic element that predisposes an individual to the development of a disease" (Venes, 2009, p. 2046) or other adverse health condition. (16)

Risk management: "The process that applies information obtained through the risk assessment process to determine whether the assessed risk should be reduced and, if so, to what extent" (Slikker, 1995). (16)

Robotics: The application of electronic, computerized control systems to mechanical devices designed to perform human functions. (25)

Rods: Visual receptors that are most plenteous, with high sensitivity but low acuity. (7)

Roll test: A clinical diagnostic maneuver used to identify horizontal canal benign paroxysmal positional vertigo (BPPV). (8)

Roll-out transfer: Beginning with sitting in a wheelchair next to a bed/mat and the lower extremities up on the mat, the individual then places an outstretched arm or elbow on the mat (arm closest to the transferring surface) and swings the other arm across the body (momentum) in order to "roll out" of the wheelchair onto the mat into a prone position. (35)

Romberg test: Test in which the patient is asked to stand unaided with feet together and arms crossed across the chest with eyes open and then with eyes closed for up to 30 seconds. The therapist observes and records the amount of sway and how long the patient can maintain this position without stepping or losing balance. (9)

Rotational chair test: Used to determine whether or not dizziness may be due to a disorder of the peripheral vestibular system or the central vestibular system. (8)

Saccadic eye movement or saccades: Small, rapid movements of the eyes as when moving from one visual target to another. (20, 29)

Saccadic latency: The time between target movement and the onset of the first saccade toward the new target location. (20)

Saccadic system: Rapid ballistic actions that quickly change the eye position from one object to another. (8)

SaeboFlex® orthosis: A custom-fitted wrist-finger orthosis that uses an extension spring system to mechanically open the hand and extend the wrist so the patient with a neurological dysfunction can practice closing the hand. (25)

SaeboReach® orthosis: A custom-fitted elbow-wrist-hand-finger orthosis that consists of the SaeboFlex wrist-finger orthosis plus an above-elbow component so the device can mechanically assist elbow extension. (25)

Salutogenic: Considering a framework for delivery of health care services, a salutogenic orientation seeks ways to affirmatively maximize health rather than remediate disease (pathogenic) or simply maintain the normal state (normogenic) (Bezner, 2007). [See normogenic and pathogenic in contrast.] (16)

Sarcopenia: Age-related loss of skeletal muscle protein mass and function. (13, 32)

Scanning training: Instruction used to teach a more effective visual scanning pattern through the use of exaggerated body movements and perceptual anchors. (31)

Scarf sign: With an infant in the supine position, the elbow can be pulled horizontally across the chest extending beyond midline, indicating low muscle tone. (18)

Scoliosis: Abnormal lateral curvature of the spine. (11)

Screening: A simple yet intentional assessment that is applied to individuals who are typically without clinical manifestations in order to identify individuals who are at risk for a specific condition. (16)

Seated position: A sitting position in which the weight is supported by the buttocks and/or thighs and the trunk is upright. (35)

Seating and mobility specialist (SMS): Certification of professionals by Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) signifying advanced knowledge and skills in seating, positioning and mobility; including assessment, funding resources, implementation of intervention, and outcome assessment and follow-up (www. RESNA.org). (17)

Secondary aging: Changes in body systems associated with increasing age but due to avoidable factors, such as inactivity, poor nutrition, stress, and exposure to environmental toxins. (37)

Secondary impairments: Organ or system deficits that develop as a secondary complication and not as a direct result of the disease process. (1, 3, 25, 37)

Secondary prevention: "(E)fforts to decrease duration of illness, severity of disease, and sequelae through early diagnosis and prompt intervention" (APTA, 2003, p. 24). (16)

Secondary progressive multiple sclerosis (MS): A type of MS that evolves when persons with relapsing-remitting MS gradually change to progressive MS secondary to their initial diagnosis. (25)

Selective motor control: [See Isolated movement.] (6)

Self-assessment: Process in which the patient evaluates and reports self-perception of task performance. (10)

Self-awareness: The ability to recognize, perceive, and reflect on aspects of one's own personality, character, and behavior/ responses. (4)

Self-determination theory: A theory of motivation, concerned with supporting natural or intrinsic tendencies to behave in effective and healthy ways. (14)

Self-efficacy: The degree to which individuals believe themselves to be capable of achieving change (Bandura, 2007). (1, 9, 28)

Self-efficacy expectations: In Social Cognitive Theory, the belief that one can successfully perform a target behavior. (16)

Self-instructional training: A type of cognitive skills training in which the individual is taught to engage in effective coping statements (i.e., self-talk) that not only keeps him focused on the task at hand but also replaces dysfunctional self-talk (e.g., "I cannot do this"; "It is going to hurt too much"). (28)

Semicircular canals: Fluid-filled loops (part of the vestibular apparatus) in the inner ear that sense angular acceleration of the head. (8, 29)

Semitandem stance: Stance posture in which the feet are placed with one more forward, not side by side. (30)

Semmes-Weinstein monofilament (SWM) aesthesiometer: A nylon monofilament embedded near the end of a plastic rod at a right angle with various thicknesses of filament used to standardize the force applied that the patient can sense. (5)

Semont maneuver (liberatory maneuver): A vestibular intervention for posterior canal benign paroxysmal positional vertigo (BPPV) that includes rapid movement from sidelying, with feet hanging off the side, quickly through sitting to lying on the other side. (29)

Senescence: The process of growing old; the process of deterioration with age. (13)

Sensation: An awareness of the state or conditions experienced by the body (inside or outside) that result from the stimulation of sensory receptors. (5, 27)

Sensibility: Responsiveness or susceptibility to sensory stimuli. (5)

Sensitivity: As related to standardized testing, a sensitive test will likely identify problems if there are any, but may falsely identify problems. [See specificity.] (13)

Sensory avoidance: Avoidance of certain sensations (such as different textures), sensory activities, or sensory situations; typically seen with hypersensitivity. (27)

Sensory conduction studies (SCS): Electrophysiologic testing performed by stimulating a cutaneous sensory nerve or a mixed nerve. (12)

Sensory defensiveness: An avoidance or fight-or-flight reaction to sensations that most people consider inoffensive. (27)

Sensory diet: A planned and scheduled daily program of specific therapeutic sensory experiences to help normalize a patient's sensory experience. (27)

Sensory integration (sensory integrity): "The organization of sensation from one's own body and from the environment, by the central nervous system, making it possible to use the body effectively within the environment" (Bundy, 2002). (27)

Sensory integration dysfunction: Impairment of central nervous system (CNS) processing of sensation (vestibular, tactile, or proprioceptive), often observed as poor praxis, modulation, or both; problems integrating sensory input in a meaningful way can impede function. (15, 27)

Sensory integration therapy: A treatment approach based on the work of Ayres to assist with integration of all sensory systems: involves meaningful activities to focus on enhanced sensation (tactile, vestibular, and proprioceptive), active participation, and adaptive interaction (Bundy, 2002). (15, 27)

Sensory neglect: An unintentional lack of awareness of the part of the body with a sensory loss. (27)

Sensory nerve action potential (SNAP): Action potential recorded during a sensory conduction study. (12)

Sensory processing: Sensory functions in the central nervous system including reception, modulation, integration, and organization of sensory stimuli, and the behavioral responses to sensory stimulation (Bundy, 2002). (27)

Sensory retraining: A sensory treatment program used to enhance an individual's appreciation of tactile, vestibular, and proprioceptive sensations; typically used in individuals with hyposensitivity. (27)

Sensory stimulation: Varied techniques used to promote sensory integration; involves the direct application of sensory stimulation with the purpose of eliciting a generalized behav-ioral response for therapeutic purposes. (15, 27)

Sensory threshold: The lowest point at which a sensory stimulation can be perceived. (27)

Sequelae: Deficits that develop as a secondary complication and not as a direct result of the disease process. (1)

Serial casting: Prolonged stretch delivered through the application of a series of casts (changed about weekly) with progressively increased range with each application, to address limited range of motion, contractures, or spasticity. (19, 23)

Serial task: A motor task composed of a series of discrete parts. (25, 37)

Shaping: A highly systematic, task-oriented, movement retraining method used in constraint-induced movement therapy to intentionally progress the demands in a motor training activity such that the final objective is approached through successive approximations. (15, 25, 33)

Sharpened Romberg test: A variation of the Romberg test in which the feet are placed in a tandem heel-to-toe position. (9)

Shortened held resisted contraction (SHRC): An isometric contraction in a shortened range held against low-intensity resistance; used to promote postural stability and increase muscle strength. (35)

Short-sitting: A sitting position in which the weight is on the buttocks and upper thighs, the shoulders are aligned over the hips in all planes, the hips and knees are at 90 degrees of flexion, and the feet are flat on the floor. (35)

Short-term goal (STG): A statement of expected achievement that specifies: (1) who will perform the behavior, (2) what the specific behavior is, (3) under what conditions the behavior will be performed, and (4) how the outcome will be measured. Reflects a limited time span, generally 2 to 3 weeks. (2)

Shoulder sling: [See single strap hemisling.] (18)

Shoulder strapping/taping: Using tape on the shoulder in a manner to reduce shoulder subluxation. (18)

Shoulder subluxation: A separation of the head of the humerus from the glenoid fossa; the inferior distraction of the humerus results in a strain on the soft tissues surrounding the shoulder joint. (18)

Shoulder-hand syndrome: Complex regional pain syndrome type 1. (28)

Shuttle walk test: An exercise test in which the patient walks back and forth a prescribed distance at a prescribed advancing pace. (11)

Sick-role behavior: "The activity undertaken by those who consider themselves ill, for the purpose of getting well. It includes receiving treatment from appropriate therapists, generally involves a whole range of dependent behaviors, and leads to some degree of neglect of one's usual duties" (Kasl and Cobb, 1966a, p. 246; 1966b, p. 531). (16)

Side sitting: Sitting upright with weight-bearing primarily on one hip that is in abduction and external rotation while the other hip is in adduction and internal rotation. (35)

Signs: Abnormality in patient status or response observed by the therapist or health-care worker and serves to indicate the presence or existence of an underlying issue. (2)

Single strap hemisling: A device for positioning a flaccid or hypotonic upper extremity against the body in adduction and internal rotation using a single strap that goes around the back of the neck with one end forming a loop to support the elbow and the other end looping around the wrist. (18)

Single-limb support (SLS) or single support phase: Period during the gait cycle when full body weight is supported by a single stance limb. (10, 37)

Sinoatrial node: The pacemaking center in the right atrium. (32)

Sitting: [See Seated position.] (35)

Sit-to-stand: Process of moving from a sitting position to a standing position. (10)

Size principle: The normal order of motor unit (MU) activation is initial recruitment of the smaller, slow MUs, followed by activation of the larger, fast MUs as demand for force generation increases. (22)

Skill: Ability to perform functional tasks with economy of effort and normal timing; ability to manipulate or move within the environment. Defined by Rood as maintaining a stable posture while the free distal part moves. For the upper extremity this means manipulating the environment, for example, open-chain activities like brushing hair. For the lower extremity, this means exploring the environment, for example, a combination of open-chain and closed chain activities like creeping or walking. (15, 18, 35)

Slow reversal (SR): Rhythmic concentric contractions alternating between agonist and antagonist muscle groups without relaxation between contractions. (15, 24, 34, 35)

Slow reversal hold (SRH): Rhythmic concentric contractions alternating between agonist and antagonist muscle groups (as in slow reversal) with an isometric hold at the end of each direction. (34, 35)

Slow reversal hold (SRH) through decrements of range: Completion of SRH, gradually decreasing the range of movement with each repetition from larger movements to smaller movements and ending in a static hold in midline. (35)

Smooth pursuit eye movement: Volitional eye movements that keep moving targets on the fovea when the head is stationary. (8, 29)

Sensory Nerve Action Potential (SNAP) amplitude: The amplitude of the SNAP in a sensory nerve conduction study, measured from baseline to peak (in uV). (12)

Sensory Nerve Action Potential (SNAP) onset latency: In a SNAP, the time in milliseconds between stimulation of the nerve and the take-off of the SNAP from baseline. (12)

Sensory Nerve Action Potential (SNAP) peak latency: In sensory conduction studies, the sensory latency measured to the peak of the SNAP, which is often more precisely defined than the take-off of the potential. (12)

Snellen chart: A chart with symbols of various sizes used to test visual acuity. (7)

Social cognitive theory: A health behavior theory/model (Bandura, 1977, 1986, 1995, 1997a, 1997b) that includes the constructs of self-efficacy expectations, outcome expectations, and outcome expectancies in the adoption of a target health behavior. (14, 16)

Social skills training: A type of behavioral skills training in which the individual is taught assertion (e.g., expressing needs clearly, refusing unreasonable requests from others), active listening (e.g., "What I hear you saying is…"), and expression of feelings (e.g., "When you do…, it makes me feel…"). (28)

Somatoform dizziness: Persistent subjective dizziness that is chronic and is caused by psychological factors, often with severe impairment of activities of daily living; a preoccupation with the dizziness is seen without any apparent somatic illness. (29)

Somatosensory system: Part of the sensory system concerned with the conscious perception of touch, pressure, pain, temperature, position, movement, and vibration, which arise from the muscles, joints, skin, and fascia; receptors all over the body not just in one location so excludes sense of vision, hearing, taste and smell. (9, 27)

Spasticity: An upper motor neuron disorder characterized by increased resistance to passive elongation of a muscle that is velocity dependent and more predominant on one side of the joint; exaggerated reflexes; and intermittent or sustained involuntary activation of muscles. (6, 19, 23)

Spatial summation: Simultaneous use of multiple sensory facilitation techniques. (22)

Spatiotemporal parameters: Measures of distance and time related to the various phases of gait that help describe a specific gait pattern. (10, 37)

Special senses: The senses that do not detect general somatic sensations but senses from specific locations (e.g., vision, hearing, taste, and smell). (7)

Special somatic afferent (SSA): Category of cranial nerves that receive special senses from external sources including CN II (vision) and CN VIII (hearing and vestibular). (7)

Special visceral afferent (SVA): Category of cranial nerves that receive special senses that process internal information including CN I (smell) and CN VII, IX & X (taste). (7)

Special visceral efferent (SVE): Category of cranial nerves that supply all voluntary muscles related to eating and breathing. (7)

Specificity of training: The concept that training effects are directly related to the type of training imposed on the muscle. Functional specificity of training is matching the task demands (speed and type of muscle contraction) to the functional role of the muscle. (22)

Specificity: A term related to standardized testing, problems are not typically falsely identified when there are none but all problems may not be identified. [See sensitivity.] (13)

Spinal accessory nerve: [See Accessory nerve.]

Spinal cord injury: Damage to the spinal cord that may be traumatic or disease-related. (11)

Spinal shock: A temporary condition of flaccid paralysis and loss of reflex activity below the level of the lesion in a traumatic spinal cord injury. (6, 26)

Splints: Orthoses that are applied over the surface of a limb to prevent adaptive shortening or to assist functional movement; usually refers to orthoses intended for temporary use. (17, 23)

Spontaneous nystagmus: Rhythmic horizontal eye movements with the slow phases directed to the side of low tonic output and quick phases away from the side of lesion. (8)

Spontaneous pain: Pain that is stimulus independent. (28)

Sporadic distribution: Sensory loss that follows no specific pattern of distribution and is usually asymmetrical, perhaps affecting both sides, but differently. (5)

ST segment depression: A dropping of the ST segment of the electrocardiogram (ECG) below the iso-electric line. May be indicative of ischemia. (11)

Stability: The ability to maintain symmetrical static balance with erect postural alignment with or without perturbations. (15, 18, 35)

Stability task: A task in which the base of support does not move, such as quiet sitting or standing. (25, 36)

Stabilization phase of sit-to-stand: The fourth and final phase of sit-to-stand when the body reestablishes postural control over a smaller base of support, the feet. (36)

Stable bilateral vestibular deficit: A category of vestibular disorder with reduced or complete loss bilaterally that may benefit from vestibular rehabilitation. (29)

Stable unilateral vestibular deficit: A category of vestibular disorder with reduced or complete loss in one inner ear only; may benefit from vestibular rehabilitation. (29)

Staccato speech: Speech in which each syllable is uttered separately. Can be characterized by speech uttered with more force than necessary, known as explosive speech. (21)

Stages of change: [See Transtheoretical model.] (16)

Stages of motor recovery: Originally documented by Brunnstrom as stages of recovery after a cerebral vascular accident. (15)

Stair negotiation: Transition from level ground ambulation to ascending and descending steps. (10)

Stance phase: Phase of gait in which the reference foot is on the ground. (10, 37)

Stance time: Total time the reference foot is on the ground during gait. (10)

Standard score: In standardized, norm-referenced testing, deviation of an individual's score from the mean score of the normative sample. (13)

Standardized: A test that is administered and scored in a consistent or "standard" manner. (13)

Standardized functional measure: Examination tool that rates a person's ability to perform purposeful activities in an efficient manner using a standardized protocol and rating criteria. (10)

Stand-pivot transfer: Process of moving from one surface to another by weight-bearing on the lower extremities and coming to a full standing position. (10)

Stand-to-sit: Process of moving from a standing position to a sitting position. (10)

Starling's Law: The optimal length at which a muscle can generate maximal tension based on the binding capacity between actin and myosin molecules of the muscle fibers— the optimal length-tension relationship. (22)

Static balance: Maintenance of an upright posture in the absence of self-initiated movement. (9, 30)

Static-dynamic: The ability to unweight and move a previously weight-bearing limb while the other limb remains in weight-bearing (e.g., one limb is statically holding while the other limb is moving). Considered to be a transitional stage between controlled mobility and skilled movements. (18, 35)

Step length: The distance, in the line of progression, between floor contact of one foot to floor contact with the opposite foot in gait. (10)

Step width: The distance between the midpoint of one heel to the midpoint of the opposite heel during gait. (10)

Stepping strategy: An active biomechanical motor action to maintain balance in response to displacement of the center of mass outside the base of support, by stepping with one foot in the direction of the displacement to reset the base of support. (9, 30)

Step-through pattern: A reciprocal configuration of ambulation (ground or stairs) in which the trailing foot steps past the opposite foot to a forward position or to the next higher stair step. (37)

Step-to pattern: A nonreciprocal configuration of ambulation (ground or stairs) in which the trailing foot steps to the same step or location as the opposite foot. (37)

Stereognosis: The ability to recognize, by tactile manipulation only, the form and characteristics of an object, including size, shape, weight, consistency, and texture. (5, 27)

Stiffness: The resistance felt with stretch of body tissues when the person is relaxed and not actively resisting by contracting the opposing muscle groups. (23)

Strabismus: An abnormal positioning of one eye often related to imbalance in extraocular eye muscles. Internal strabismus means the affected eye is resting in an excessively adducted position. External strabismus means the affected eye is excessively abducted. (7)

Straddle sit: A sitting position similar to long sitting (see long sitting) with the legs out wide and the hips in abduction. (35)

Stride length: The distance between floor contact of the reference foot to the next floor contact of the same foot. (10, 37)

Stroke volume: Amount of blood ejected from the heart per beat. (11, 32)

Stupor: Level of consciousness in which the person responds only to noxious stimulation, and returns to unconsciousness if stimulation stops. (4)

Subjective measures: Measures to characterize task performance that depend on perceptions, estimations, opinions, or judgments and therefore can be significantly influenced by the observer. (1, 10)

Subjective norm: The factor in the Theory of Planned Behavior that, along with attitude toward the behavior and perceived behavioral control, determines the individual's behavioral intention with respect to a target health behavior. (16)

Submaximal exercise testing: Exercise testing in which the patient does not exercise to exhaustion, but rather to volitional fatigue or less than 85% of age-predicted heart rate max. (11)

Substitution: A form of compensation in which intact strategies are used to replace an impaired system function, as opposed to true system recovery. (29)

Superficial sensation: [See Tactile sensation.] (5) Surface electromyography (EMG): A test of the electrical activity of muscles, using a surface electrode. (12)

Swing limb advancement (SLA): The phase of gait, during single-limb stance of the contralateral lower extremity, when the reference limb moves forward and then ahead of the body. (37)

Swing phase: Phase of gait in which the reference limb is off the ground and swinging forward in preparation for ground contact. (10, 37)

Swing time: Total time the reference foot is off the ground in a gait cycle. (10)

Swing-through gait pattern: Gait pattern in which the legs are advanced forward simultaneously, past the gait assistive device (e.g., crutches).

Swing-to gait pattern: Gait pattern in which the legs are advanced forward simultaneously and make contact with the ground in line with the assistive device. (26)

Symmetrical tonic neck reflex: One of the early tonic reflexes; increased extensor tone is observed in the upper extremities and increased flexor tone in the lower extremities with head/neck extension and the reverse with head/neck flexion. (13)

Symptoms: Subjective reports of change in patient's status or function of organ/system directly perceptible to the patient and reported by the patient, often reflecting the presence of an unusual state or disease; physical symptoms may be detected by objective testing. (2, 25)

Synergy: Groups of muscles that are functionally linked to move together; can occur in abnormal groups after central nervous system disorders such as stroke and brain injury. (15, 25)

Systems review: In the elements of patient/client management of the Guide to Physical Therapist Practice (APTA, 2003), a component of examination comprising a brief screening examination of core body systems. (16)

Systolic blood pressure: Arterial blood pressure during the peak systole (contraction) phase of the cardiac cycle. (11, 32)

Tabetic syndrome: A disorder with signs and symptoms that resemble those of tabes dorsalis ataxia due to impairment of the posterior columns of the spinal cord. (21)

Tachycardia: Rapid heart rate (pulse greater than 100 beats per minute). (11)

Tactile defensiveness: A negative overreaction to sensory input by touch that is typically considered nonirritating or harmless. (27)

Tactile discrimination: The ability to recognize the texture of something by touch. (27)

Tactile localization: Awareness of the specific skin surface location to which a stimulus is applied. (27)

Tactile sensation: All sensations detected by receptors at the surface of the body (skin). (5)

Tai Chi: An ancient Chinese form of smooth, flowing, focused movement, typically performed in stance, which can enhance balance and strength. (15)

Talk Test: A proxy measure of exercise intensity based on the level of difficulty of talking while exercising. (32)

Tapping: Quick brief taps to a muscle belly used to facilitate a contraction. (15)

Tardieu Scale: A scale specifically developed to rate the degree of spasticity, noting the precise point in range where resistance is first encountered at various speeds of movement and grading the quality of the muscle reaction. (6)

Target muscle: Refers to the weakened muscle that is the focus of the strengthening exercise. (22)

Task analysis: Observational analysis of the patient's movement strategy during the performance of a task. (2)

Task practice: A task-oriented movement retraining technique used with constraint-induced movement therapy in which functional tasks are practiced using the more-impaired extremity for a period of only 15 to 30 minutes. Global feedback concerning the patient's performance is provided at the end of the trial, and the task is made progressively more difficult as patient's performance improves. (25, 33)

Task-oriented interventions: Activities based on functional tasks that an individual performs throughout the day with emphasis placed on the individual's abilities, environment, and task constraints. (15)

Task-specific strength training: Strengthening concept that utilizes functional tasks to challenge the neuromuscular and musculoskeletal systems. (22)

Taste: The special sense with chemical receptors on the taste buds that allows awareness of the flavor of something, including characteristics of sweet, sour, bitter, and salty. (7)

Taxonomy of tasks: Refers to Gentile's 16 categorical observational analysis method that assesses the performance of tasks under various environmental conditions and movement requirements. (2)

Temperature sensibility: Awareness of the heat or cold state of an object or environment. (5)

Temporal measures: Timed components of gait including swing time, stance time, double/single limb support time, stride time. (10)

Temporal stages model: Systematic analysis of tasks based on their temporal sequencing (Hedman, 1996). (2)

Temporal summation: Repeated use of a single stimulus in a short time frame to produce the desired muscle response. (22)

Tendon lengthening: Surgical procedure performed under general anesthesia to lengthen muscles that have shortened as result of spasticity, positioning, or other causes to improve function; muscles commonly lengthened include gastroc-soleus, hamstrings, and hip adductors; various techniques used. (19)

Tenodesis: In patients with a C6 spinal cord injury, active extension of the wrist that results in a passive closure of the hand, especially when there is some tightness in the long finger flexor tendons. (33)

Tenodesis grasp: A hand grasp accomplished by extending the wrist, (which puts tension of the mildly contractured long finger flexor tendons), in individuals with C6 or C7 tetraplegia (who do not have long finger flexor action to create a hand grasp). (26)

Tenodesis grip: Adaptive shortening of the finger and thumb flexors resulting in a functional nonorthotic grip such that the fingers flex when the wrist is extended. (35)

Terminal feedback: Feedback that is given at the end of a movement or immediately after a movement, such as stand-to-sit. (36)

Termination: Stage in the Transtheoretical Model (Stages of Change) in which the person no longer succumbs to temptation and has total self-efficacy. (16)

Tertiary prevention: "(E)fforts to decrease the degree of disability and promote rehabilitation and restoration of function in patients with chronic and irreversible diseases" (APTA, 2003, p. 24). (16)

Tetraplegia (or formerly Quadriplegia): Impairment or loss of motor and/or sensory function in the cervical segments of the spinal cord, causing paralysis of the lower extremities and trunk and some or all upper extremity muscles. (5, 11, 26)

Theory of Planned Behavior: A health behavior theory/model (Ajzen, 1991; Ajzen and Driver, 1991; Ajzen and Madden, 1986) in which the adoption of a target health behavior is determined by an individual's behavioral intention, which in turn is determined by the attitude toward the behavior, subjective norm, and perceived behavioral control. (16)

Therapeutic drug monitoring: Laboratory measures that analyze therapeutic drug concentrations in body fluids to ensure that safe and effective drug levels are achieved and maintained. (12)

Therapeutic or Swiss ball: Commercially available balls designed to support body weight. Used for interventions to increase strength and promote postural control on an unstable base with patients supine, prone, or sitting on the ball. Can be used to aid in achieving multiple intervention goals. (15)

Thixotropy: A substance or tissue (such as muscle tissue) that demonstrates increased stiffness when it has not been moved recently, with decreased resistance after recent movements. (23)

Threshold stimulus: Also known as the limen, the minimal stimulus that results in a sensation. (5)

Thrombocytopenia: A decrease in the number of circulating platelets. (12)

Thrombocytosis: An increase in the number of circulating platelets. (12)

Tic: A sudden, spasmodic, rapid, painless, recurring, nonrhythmic, stereotyped muscle contraction, particularly of the face, or vocalization. (20)

Tic douloureux: [See Trigeminal neuralgia.]

Tidal volume (VT): The volume of air expired with each breath. (32)

Time constant: In electromyographic (EMG) biofeedback (BFB), the sampling frequency of the EMG signal, reflecting how often the EMG information is updated to the viewer for BFB. (22)

Timing of movement: The sequence in which the components of limb movement are taking place during a functional task. (21)

Tinnitus: The subjective perception of sound, usually described as "ringing in the ears," in the absence of a true environmental sound. (29)

Titubation: A rhythmic tremor mainly of the head and/or upper trunk, observed in cerebellar dysfunction, primarily present in the antero-posterior plane with a frequency of 3 to 4 Hz. (6, 21)

Tonic labyrinthine reflex: One of the early tonic reflexes characterized by a generalized increase in flexor tone with prone positioning and a generalized increase in extensor tone with supine positioning. (13, 15, 34)

Tonic muscles: Deep one joint muscles involved in maintaining postural stability through long sustained muscle contractions. (15)

Tonic reflexes: Early reflexes (mediated by the spinal cord and lower brainstem) that create alterations in muscle tone in large parts of the body in response to head or body position; variable appearance in typically developing infants up to 6 months of age; never obligatory or limiting in typically developing infants; can be persistent and severe in infants/children with neuromo-tor problems. (13)

Torsional nystagmus: Refers to a rotary movement of the globe of the eye. (8)

Total peripheral resistance: A measure of the total resistance to blood flow through the systemic blood vessels. (32)

Toxicology: Laboratory measures that analyze body fluids for the identification and quantification of toxins (e.g., alcohols, heavy metals, pesticides, etc.) and illegal drugs. (12)

Tracking resistance: Using light resistance against the intended direction of movement that facilitates movement into that direction. (18)

Tracking test: Performed as part of electronystagmography (ENG) or videonystagmography (VNG) to evaluate movements of the eyes as they follow a moving visual target. (8)

Transcutaneous electrical nerve stimulation (TENS): Low-intensity electrical stimulation causing sensory stimulation without muscle contraction. (24, 28)

Transfer: Moving from one sitting surface to another, closely positioned sitting surface. (10)

Transfer package: A set of techniques within constraint-induced movement therapy (CIMT) used to hold the patient accountable for adherence to the requirements of the therapy. (25)

Transitional movements: Movements from one position to another (e.g., sit to stand); changes in body position. (10)

Transitional multiple sclerosis (MS): A phase of MS between relapsing-remitting MS and secondary progressive MS in which relapses decrease over time. (25)

Transtheoretical model: A health behavior theory/model (Prochaska, 1979) that involves 6 stages in the adoption of a target health behavior. (16)

Transverse temporal gyri of Heschl: The primary auditory cortex located in the superior temporal lobe. (7)

Treatment intervention: Skilled and purposeful interactions between the physical therapist, patient, family, caregiver, or other appropriate individuals, and the various different procedures and techniques included in the practice of physical therapy. (2)

Tremor: A type of dyskinesia that involves involuntary, rhythmic, oscillatory movements of reciprocally innervated muscles. Tremors can occur at rest or during movement and vary in frequency. Types include: Resting (3–6 Hz), Action, or Postural (4–12 Hz). (20)

Trigeminal nerve: Cranial nerve V that conveys sensation from the face, cornea, mouth, and teeth, and provides motor innervation to the muscles of the jaw. (7)

Trigeminal neuralgia: A pathological condition of cranial nerve V characterized by brief but repeated sharp, excruciating pain in the face, often with resulting facial motor tics. (7)

Trochlear nerve: Cranial nerve IV that supplies the superior oblique extraocular muscle. (7)

Two-point discrimination: The ability to distinguish two simultaneously applied blunt points of contact as two discrete stimuli. (5)

Unified Parkinson's Disease Rating Scale (UPDRS): A multidimensional scale used to assess the underlying impairments and functional activity limitation often associated with the progressive stages of Parkinson disease. (6)

Unilateral distribution: A pattern in which symptoms occur on a single side of the body, usually contralateral to the side of cerebral pathology. (5)

Unilateral spatial neglect (USN): Inattention to the side of the body opposite of a brain lesion. (4)

Unstable unilateral or bilateral vestibular deficit: A category of vestibular disorder with reduced or complete vestibular loss in one or both ears, in which the expression of the disorder may frequently change; patients may not obtain benefit from vestibular rehabilitation. (29)

Unsteadiness: A sensation described as feeling "off" or "drunk-like" and may cause the individual to be afraid of falling. (8)

Upper extremity (UE): All the muscular, skeletal, nervous, and soft tissues of the shoulder girdle, upper arm, forearm, and hand. (33)

Upper-motor neuron (UMN) lesion: Any pathology that affects upper-motor neurons in the brain and spinal cord, resulting in weakness and an increase in spinal reflexes. (6, 26)

Upper-motor neuron syndrome: Common clinical constellation of symptoms associated with upper-motor neuron lesions including spastic muscle tone, clasp-knife resistance, scissoring gait, clonus, and positive Babinski and Chaddock signs. (6)

Upper-motor neurons: All neurons originating in the central nervous system that effect or control lower-motor neurons. (6)

Upright mobility: The skills of moving one's body from one place to another while maintaining an upright position, including walking, walking on ramps and curbs, and ascending/ descending stairs. (37)

Use-dependent brain plasticity: Use of a body part that leads to an expansion of the brain's representational zone corresponding to that body part. (25)

Vagus nerve: Cranial nerve V that carries sensory information from major visceral organs and supplies parasympathetics to the gastrointestinal, cardiovascular, and respiratory systems. (7)

Validity: The extent to which a test or measure truly measures what it is intended to measure. (3, 13)

Variability: Flexible movement patterns and adaptability to task demands. (13)

Velocity-tension relationship: The inverse association between muscle tension and velocity of movement during concentric contractions; as movement velocity increases, the muscle's ability to generate force decreases. (22)

Ventilation: Process where gases are moved into and out of the lungs. (11)

Ventilatory efficiency: The ratio of minute ventilation to carbon dioxide. (32)

Ventilatory reserve: The difference between maximal available ventilation and ventilation during exercise. (32)

Ventricular arrhythmias: Abnormal heart rhythms initiated by abnormal electrical activity in the ventricles. (11)

Verbal apraxia: Awkward or distorted speech in the absence of motor weakness or paralysis. (4)

Vergence: Eye movements in which the eyes move in opposite directions. Vergence may be observed as convergence, adduction of both eyes as the visual target moves closer to the face, or divergence, abduction of both eyes as the visual target moves farther from the face. (8)

Vertigo: A vestibular symptom described as an illusion of movement that includes a "spinning" sensation, with either the room spinning or a feeling of spinning inside the head. (8, 29)

Vestibular adaptation: The ability of the vestibular system to change how it responds to stimuli as a significant part of vestibular recovery. (29)

Vestibular evoked myogenic potential (VEMP): A test of the neurophysiological response of the otolith organs (utricle and saccule) of the inner ear using a prescribed kinematic (motion) stimulus. (29)

Vestibular neuritis: Inflammation of the vestibular nerve. (8, 29)

Vestibular rehabilitation therapy (VRT): The set of all therapeutic approaches, exercises, and activities that is used to remediate vestibular impairment, when possible, and to restore optimal functional activity. (29)

Vestibular spinal reflex (VSR): The influence of vestibular stimulation to stabilize the body and provide postural control after pertubation. (8, 29)

Vestibular system: The body system that provides information based on what can be sensed about head and body position in space, using the vestibular organ. (9)

Vestibulocochlear nerve: Cranial nerve VIII that includes divisions for vestibular sensation and auditory sensation. (7)

Vestibulo-ocular reflex (VOR): A reflexive eye movement in response to head movement that enables a person to keep the environment focused during head motion and provide gaze stability. (8, 9, 29)

Vibration: The sensation that results from contact with an object that is shaking or oscillating at a particular frequency. High frequency (100–300Hz) vibration applied to a muscle belly activates the muscle spindle 1a afferents causing a reflex (tonic vibratory reflex) contraction of the muscle. (5, 18)

Videonystagmography or electronystagmography: Laboratory test that measure eye movements with the use of video recording and/or electrodes, respectively, during caloric, positioning and visual tracking tests. (8, 29)

Virology: Laboratory measures that analyze body fluids and tissues for the identification of infectious viruses. (12)

Virtual environments: Use of computers to create the illusion of being active in a simulated world with an opportunity to practice meaningful tasks. (25)

Virtual presence: The illusion of entering the computer-generated virtual environment with convergence of multisensory inputs (visual, auditory, touch). (25)

Virtual reality (VR): Use of computer technology to simulate real-world environments and address impairments of cognition and motor function. (25)

Virtual reality (VR): Immersive: VR that includes use of large-screen projection, head-mounted displays, and cave systems in which the environment is projected onto a concave surface to increase the sense of immersion; may also use environments such as video capture systems in which the user views herself or an avatar (representation of the limb) in the scene on a computer screen as if watching television. (25)

Virtual reality (VR): Nonimmersive: VR in which users interact in different degrees with the environment displayed on a computer screen, with or without interface devices such as a computer mouse or haptic devices such as CyberGloves, joysticks, or force sensors. (25)

Virtual reality (VR)–augmented rehabilitation: VR provided as an adjunct to traditional rehabilitation. (25)

Virtual reality (VR)–based rehabilitation: VR provided alone, without traditional rehabilitation. (25)

Vision: The special sense that allows one to see the environment. (7)

Visual discrimination: Process of recognizing depth, spatial relation between objects, and forms. (4)

Visual field: The area of the environment that can be simultaneously seen with one eye without movement. (7)

Visual fixation: Refers to a person's ability to maintain visual focus on a stationary target. (8, 29)

Visual system: The body system that provides information based on what can be seen, using the eyes. (9)

Vestibular ocular reflex (VOR) X1 viewing: An exercise involving movement of the head in a horizontal or vertical direction while the target remains stable. (29)

Vestibular ocular reflex (VOR) X2 viewing: An exercise involving movement of the head in a horizontal or vertical direction while the target moves simultaneously in the opposite direction. (29)

Watsu: A gentle form of body therapy performed in warm water that combines elements of massage, joint mobilization, shiatsu, muscle stretching, and dance. (15)