THE TEMPORAL-DISTANCE EFFECT IN SUBJECTS WITH DEMENTIA OF THE ALZHEIMER-TYPE

The efficacy of temporal-distance processing for spatial locations was evaluated in college students, elderly controls, and subjects with mi ld and moderate dementia of the Alzheimer type (DAT). The elderly cont rols showed a slightly lower level of performance than college student s, but both elderly controls and college students displayed a temporal -distance effect. The mild DAT subjects performed the task accurately only at the greatest temporal distances. The moderate DAT subjects per formed at chance levels for all distances. Because similar changes in the temporal-distance function have been described for humans and anim als with small hippocampal or prefrontal cortex damage, there might be important hippocampal or prefrontal cortex involvement or both in ear ly stages of Alzheimer disease.