Memory Scanning Performance in Healthy Young Adults,Healthy Older Adults,and Individuals with Dementia of the Alzheimer Type

A memory scanning (Sternberg, 1966, 1975) task was administered to healthy young adults, older adults, and two groups of individuals with dementia of the Alzheimer's type (DAT) to determine age- and disease-related changes in the retrieval of information from short-term memory. Healthy older adults, in comparison to healthy young adults, displayed increases in both slopes and intercepts in memory scanning. Individuals at various stages of DAT (very mild, mild, moderate) displayed increases in both slopes and intercepts compared to nondemented age-matched control individuals. There was also some evidence that DAT individuals are more likely to engage in a self-terminating search instead of an exhaustive search of short-term memory.