Visual variant of Alzheimer disease: Distinctive neuropsychological features

A subgroup of patients with probable Alzheimer disease (AD) reported a history of isolated visual disturbances (VS) early in the course of disease, without the characteristic memory complaints. Brain imaging and neuropathologic studies indicated that this subgroup had larger involvement of visual cortical areas and relative sparing of temporal, frontal, and limbic structures compared with classic AD. Consistent with these Endings, the authors hypothesized that the cognitive deficits in this subgroup would be distinctly different from those seen in more typical AD patients. The authors studied 10 probable AD patients with VS (AD+VS), 22 patients without VS (AD-), and 25 healthy controls with a neuropsychological test battery. Compared with AD-, AD+VS patients performed significantly better on tests of verbal memory and had greater impairment on tests of visuospatial skills, suggesting a distinct pattern of cognitive dysfunction consistent with metabolic and neuropathologic reports.