APA Dictionary of Psychology

a progressive hereditary disease associated with degeneration of nerve cells, particularly in the caudate nucleus of the basal ganglia and in the cerebral cortex. It is characterized by abnormalities of gait and posture, motor incoordination, and involuntary jerking motions (chorea) as well as dementia, mood disturbances, and personality and behavioral changes. The age of onset is usually between 30 and 50, but there is a juvenile form of the disease in which symptoms first appear before the age of 20. Huntington’s disease is inherited as an autosomal dominant trait (see dominant allele); the single gene responsible is located on chromosome 4. Also called Huntington’s chorea. [George Huntington (1850–1916), U.S. physician]