A newly defined familial disorder of progressive dementia, ataxia, chorea, and seizures is described from the Department of Neurology School of Medicine, the University of North Carolina at Chapel Hill and the Department of Pathology, Duke University Medical Center, Durham, N.C. The first recorded member of the family was born in 1840 and lived at Haw River, N.C. In 22 patients examined the initial symptoms were ataxia of gait, intention tremor and choreiform movements that developed usually between 15 and 30 years of age. Recurrent generalized tonic-clonic seizures and progressive dementia developed later, and 11 of the 22 died after 15-25 years of illness. Neuropathological findings in two deceased family members were: neuronal loss of the dentate nucleus, microcalcification of the globus pallidus, neuroaxonal dystrophy of the nucleus gracilis, and demyelination of the centrum semiovale. 
COMMENT. The authors list in the differential diagnosis: Olivopontocerebellar atrophy, dentatorubropallidoluysian atropy, Ramsay Hunt syndrome, familial idiopathic calcification of the basal ganglia, neuroaxonal dystrophy, Hallervorden-Spatz disease, Huntington's disease, Wilson's disease, and Gerstmann-Straussler syndrome (cerebellar ataxia, dementia, amyloid plaques). Farmer's syndrome appears to have distinctive features.
Dementia as defined by the American Psychiatric Association (1980) is a deterioration in cognitive abilities that exceeds the decline expected with normal aging and occurs in a state of clear consciousness. Classifications of the dementias have been based on etiology (degenerative, vascular, toxic metabolic, and infectious), pathology, and clinicopathological correlations. Cortical versus subcortical forms have been described and have been correlated with brain behavior relationships. In Alzheimer's disease corticopathology is prominent whereas in Parkinson's disease and Wilson's disease subcortical areas are the major sites of pathology. This dichotomy is probably an oversimplification. (See ).