a form of hyperkinesia characterized by rapid movements such as twitching of the extremities, winking, and smacking of the lips. It is associated with organic injury to certain subcortical sections of the brain. The most common form is chorea minor, or Sydenham’s chorea, usually found in children and adolescents as an indication of rheumatism. In addition to hyperkinesia, other characteristics of chorea are low muscle tone and such asthenic symptoms as sleeplessness, lacrimation, and irritability. Sydenham’s chorea usually takes a favorable course, but recurrences are possible. The condition known as chorea major, marked by hysterical choreiform twitchings that were observed as a mass phenomenon in the Middle Ages, is now of historical interest only.
Huntington’s chorea (described in 1872 by the American psychiatrist G. Huntington) is a hereditary degenerative disease transmitted as an autosomal dominant trait. It usually occurs between the ages of 35 and 40 and is characterized by chronic progressive deterioration. Muscle tone is low in some cases, and high (with muscular rigidity) in others. The principal characteristics of Huntington’s chorea are such forms of mental deterioration as apathy, loss of memory, intellectual decline, transient delusions, hallucinations, and the gradual development of severe dementia. Other findings in Huntington’s chorea include subcortical lesions and atrophy of the brain cortex.
Sydenham’s chorea is treated with antirheumatic drugs (including salicylates), sedatives, and antiallergens (such as diphenhydramine and chloropyramine). Chlorpromazine and reserpine are prescribed for Huntington’s chorea; drugs used in the case of muscular rigidity include cholinolytic agents (such as trihexyphenidyl hydrochloride), L-dopa, and amantadine hydrochloride.
V. A. KARLOV