The role of selective attention in the visuo-spatial memory of patients suffering from dementia of the Alzheimer type.

The visuo-spatial memories of groups of dements suffering from Alzheimer's disease (DAT) and multi-infarct dementia (MID) were compared with those of low-IQ but non-dementing elderly volunteers. In contrast to the other two groups, the DAT subjects were hindered when extra visual information was available as a memory aid. Similarly, DAT subjects' performance on a visual search task was worsened when the displays were made more varied. The concept that DAT patients' visuo-spatial memory problems may be due to a failure of selective attention is discussed.