Age Differences in Memory: Demands on Cognitive Control and Association Processes

Abstract

Publisher Summary This chapter describes the age differences (or lack thereof) for several major forms of memory, with particular attention to the age differences in brain structure or function that may underlie them. Age differences in memory are often linked to age differences in frontal brain regions and in cognitive control. Reducing control demands often reduces and sometimes eliminates age differences in memory performance. However, predicting age differences in performance is not simply a matter of quantifying the control demands of a task. Changes in frontal regions are quite prominent, but not the only changes that occur. Besides the changes within brain regions, white-matter declines also impact communication between regions. Changes in sensory and motor systems may affect both the quality of information that older adults receive and the quality of their output. Early neuroimaging studies emphasized age-related underactivations. These findings fit well with the behaviorally derived view that many of older adults' memory difficulties arise from a failure to engage the processes needed to support successful remembering. These processes, especially at the encoding stage, are thought to be effortful and demanding. Age changes in brain function, perhaps especially frontal brain functions related to attention, might make such processes more “expensive” for older adults to engage.