The Disordered Mind: What Unusual Brains Tell Us About Ourselves

by Eric R. Kandel

Approximately thirty thousand people in the United States have Huntington’s disease, a disorder that affects both sexes equally. The age at which the disease first appears varies widely, but the average age of onset is forty. The disorder was first described in 1872 by George Huntington, a Columbia University–trained physician who noted the hereditary nature, involuntary movements, and changes in personality and cognitive functioning that characterize the disorder. His description was so clear and so accurate that other physicians could readily diagnose the disorder, and they named it after him. Unlike Parkinson’s disease, which is fairly localized at first, Huntington’s disease can become more widespread quite early and can lead to cognitive as well as motor defects, including sleep disorders and dementia. It primarily affects the basal ganglia, but it also affects the cerebral cortex, the hippocampus, the hypothalamus, the thalamus, and occasionally the cerebellum (fig. 7.4).