Remote memory for visuospatial information in patients with Alzheimer's disease

Remote memory for visuospatial information was studied in patients with dementia of the Alzheimer type (DAT) using a test of geographic knowledge previously employed in a study of patients with Huntington's disease. When asked to locate places on a map of the region of the United States in which they were born and raised or on a map of California where they currently resided, the DAT patients performed less accurately than controls. However, unlike controls, the performance of DAT patients in locating places was relatively more accurate using the map of the region in which they were born and raised than using the map of California. Thus, the DAT patients exhibited temporally graded retrograde amnesia for visuospatial knowledge, which parallels the pattern of retrograde amnesia reported for DAT patients when remote memory was assessed with tests requiring identification of famous persons or recall of past public events.