Oculomotor reaction time in dementia reflects degree of cerebral dysfunction.

The effects of diffuse cerebral dysfunction on oculomotor reaction time were assessed in patients with dementia of presumed Alzheimer's etiology and in normal age-matched control subjects. Patients were classified into mild, moderate, and severe groups on the basis of independent neurological, neuropsychological, and neuroradiological ratings for disease severity. Saccadic latencies to targets appearing in parafoveal and near peripheral vision showed significant increases from the normal controls to dementia groups, with each severity subdivision clearly differentiated from the others in terms of mean oculomotor reaction time. These data offer strong evidence for a direct relationship between degree of cortical structural integrity and simple oculomotor reaction time and suggest a higher cortical regulatory role in sensory-motor integration.