Emotional Memory in Aging: Cognitive & Neural Processes

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DESCRIPTION (provided by applicant): The material and memories of everyday life are often infused with an emotional relevance that is not present, and may even be avoided, in traditional studies of memory in aging. To date, few studies have investigated the cognitive and neural substrates of emotional memory in older adults, and none has investigated behavior, brain structure, and brain physiology in a single study of emotional memory in any participant group. To fill this gap, we will adopt a two-pronged approach: a series of behavioral experiments that will show the extent to which emotional valence conveys a benefit on the quantity and, significantly, the quality of information remembered by older adults; and related structural and functional magnetic resonance imaging experiments using advanced technology. These investigations will allow us to uncover the neural structures that underlie emotional memory in younger adults, and altered and preserved emotional memory circuits in older adults. In young adults, memory is typically better for emotional as compared to neutral stimuli. Evidence from our laboratory and others suggests that older adults also show enhancement based on emotional valence. It is unclear, however, whether normal aging affects the cognitive or neural mechanisms supporting a specific component of emotional enhancement: the increased ability to remember rich details of a negative event. This question is of particular interest because older adults have difficulty recalling specific details of non-emotional events (as compared to remembering the gist of the events). Recollective memory for neutral items is thought to rely on the hippocampal formation, and we predict that the recollective enhancement for emotional stimuli results from connections between the amygdala, other medial temporal lobe structures, and prefrontal cortex. In contrast to older adults' ability to show enhancement based on the arousal or valence of an item, we found that older adults do not show enhancement for neutral stimuli embedded in a negative versus a neutral context. A second goal of the proposed research is to examine whether this deficit is present across a range of stimuli, and whether the impairment is related to dysfunction of specific brain regions. Because of the particular role of prefrontal cortex in binding an item to its context, or source memory, we propose that older adults' reduced enhancement may be due to structural or functional alterations in prefrontal cortex.