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motion artifact

Blurring of a radiographic image, produced by respiratory, muscular, or other movement of the patient.

motion-mode display

M-mode ultrasound.

motion scaling

In robotic surgery, the conversion of the surgeon’s large hand movements into smaller movements of the surgical instrument in the operative field.

motion sickness

SEE: under sicknes.


(mōt″ĭ-vā′shŏn) The internal drive or externally arising stimulus to action or thought. motivational (mōt″ĭ-vā′shŏn-ăl), adj.

motivational enhancement therapy

A form of psychotherapy to overcome ambivalence and help people to reach desired goals. It is used to treat alcoholism, drug dependency, and anorexia/bulimia.

motivational interviewing

ABBR: MI. Client-centered psychotherapy in which patients are encouraged to explore the discrepancies between what they hope to attain in their lives and how they currently live and behave. The therapist uses empathy while helping patients explore how change may positively affect their lives. Patients’ natural resistance to change is accepted as normal and natural. Autonomy is fostered so that changes in speech and behavior are developed by the patient, not by the therapist. The technique is used in a variety of settings, including alcohol and drug rehabilitation.


(mōt′iv) [L. motivus, pert. to, causing, or in motion] A need, reason, or want that impels action.


(mō″tō-fā′shĕnt) Producing motion.


(mōt″ŏ-noor′on″) A motor neuron. SEE: motor neuron.


[L. motor, mover] 1. Causing motion. 2. In anatomy, pert. to neurons or axons involved in the output of the nervous system; efferent. 3. In psychology, pert. to neural events relating to motions made by the body. 4. A part or center that induces movements, as nerves or muscles. 5. A structural mechanism producing motion. motorial (mō-tor′ē-ăl), adj.

motor area

The posterior part of the frontal lobe anterior to the central sulcus, from which impulses for volitional movement arise.

Motor Assessment Scale

SEE: under 1scale.

motor control

The neural and biomechanical basis of planned, coordinated movement. SEE: motor learning.

Motor-Free Visual Perception Test

A standardized test of visual perception that does not require motor performance.

motor impersistence

Inability to sustain muscle strength, e.g., to protrude the tongue without it darting uncontrollably, or to hold a cup steadily in the hand for more than a few seconds.

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