AGE-RELATED CHANGE IN VISUAL INFORMATION-PROCESSING - TOWARD A UNIFIED THEORY OF AGING AND VISUAL MEMORY

Memory for semantic information is relatively preserved through the no rmal aging process. Visuospatial memory remains less intact. In the pr esent article a theory is proposed that links this processing differen ce to normal age-related generalized cognitive slowing, and to the app earance of specific age-related differences in memory performance. Evi dence for these suggestions is presented from work in four areas: ment al rotation, spatial memory, paired-associates learning, and free reca ll. Cognitive performance in young and older respondents is shown to v ary predictably with systematic variation of visuospatial and semantic stimulus factors consistent with these hypotheses, A further test of these ideas derives from the development of a clinically useful mnemon ic system for older adults that is based on these principles. Taken to gether, this research indicates that much of the deficit observed in t he memory performance of older adults may derive not from memory probl ems per se, but: rather from the action of generalized cognitive slowi ng, which contributes to diminished abilities to represent and process visual images. This series of findings may provide a framework for un derstanding a wide variety of the processes involved in aging and visu al memory, and for the creation of applications to aid the memory of o lder adults.