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(ă-ten′dănt) A paramedical hospital employee who assists in the care and personal support of patients.


(ă-tend′ing) Pert. to or being the physician or surgeon having primary responsibility for a patient.


(ă-ten′shŏn) Direction of the consciousness to a person, thing, perception, or thought.

attentional bias

(ă-ten′shŏn-ăl) An error in diagnosis or other form of analysis in which a person is unable to see the truth because he or she does not perceive a critical piece of data.

attentional set shifting

Set shifting.

attention-deficit hyperactivity disorder

ABBR: ADHD. A persistent pattern of inattention, hyperactivity and impulsivity, or both, occurring more frequently and severely than is typical in those at a comparable level of development.

image ADHD may sometimes be confused with other disorders.

 INCIDENCE: ADHD is the most commonly reported neurobehavioral disorder of childhood. In the U.S., approx. 10% of children (5.4 million children) between age 6 and 17 are diagnosed with the disease. The illness may begin in early childhood but may not be diagnosed until after the symptoms have been present for many years. The prevalence of the disorder has climbed rapidly in the last few years. The CDC estimates that one in five boys in high school and one in nine school-age children have been assigned the diagnosis.

 SYMPTOMS AND SIGNS: Signs may be minimal or absent when the person is under strict control or is engaged in very interesting or challenging situations. Signs are more likely to occur in group situations. Although behaviors vary widely, affected patients typically exhibit motor restlessness, impulsivity, and difficulty in concentrating on a single task or chore. They tend to do more poorly in school than one might predict based on assessments of their intelligence. Although characteristics of ADHD are found in many people at one time or another, a key feature is the excessive or unusual pattern of behavior outside normal bounds of exuberance or excitement. The findings must be severe enough to be maladaptive and inconsistent with specified levels of development and last at least 6 months.

 DIAGNOSIS: The disorder is difficult to diagnose in children under age 5. It is important to distinguish ADHD from age-appropriate behavior in active children and from disorders such as mental retardation, primary learning disabilities, alteration of mood, anxiety, petit mal seizures, or personality changes caused by illness, family stress, or drugs. The criteria determined by the American Psychiatric Association include specific limits concerning the duration and severity of symptoms of inattention and hyperactivity-impulsivity. The findings must be severe enough to be maladaptive and inconsistent with specified levels of development.


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