Development of neuropsychological deficits in Huntington's disease.

Patients with more recently diagnosed Huntington's disease (RHD) were compared on a neuropsychological test battery with patients who had had the disease one to eight years (moderate HD) and with asymptomatic offspring. Though the patients with HD showed deficits in motor and motor-independent abilities, the patients with RHD were less impaired on factors assessing visuospatial ability, cognitive flexibility, and motor steadiness. Of particular interest was the finding that some asymptomatic offspring showed deficits in visuospatial ability and auditory memory that resembled the deficits of patients with RHD. The findings suggest that deficits in HD do not develop at a uniform rate; deficits in cognitive flexibility occur in later stages of the disease; and visuospatial and auditory memory deficits are very early signs and are present in some asymptomatic offspring.