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Neural Processes Supporting Young and Older Adults Emotional Memories Elizabeth A Kensinger1 2 and Daniel L Schacter2 3 Abstract Young and older adults are more likely to remember emotional information than neutral information The present functional magnetic resonance imaging study examined the neural processes supporting young ages 18 35 and older ages 62 79 adults successful encoding of positive negative and neutral objects e g a sundae a grenade a canoe The results revealed general preservation of the emotional memory network across the age groups Both groups recruited the amygdala and the orbito frontal cortex during the successful encoding of positive and negative information Both ages also showed valence specific recruitment right fusiform activity was greatest during the successful encoding of negative information whereas left prefrontal and temporal activity was INTRODUCTION Individuals typically are more likely to remember emotional information than they are to remember nonemotional information LaBar Cabeza 2006 Reisberg Heuer 2004 Buchanan Adolphs 2002 Although the neural processes corresponding to this emotional memory enhancement have been thoroughly studied in young adults with activation in the amygdala and the orbito frontal cortex corresponding with later memory for emotional material LaBar Cabeza 2006 Hamann 2001 little is known about how the emotional memory network changes with age The primary goal of the present study was to examine the neural processes that correspond with young and older adults successful encoding of emotional information On the one hand there is reason to believe that the emotional memory network may be fairly stable with aging Some behavioral studies have suggested that older adults display emotional memory enhancements comparable to those of young adults e g Denburg Buchanan Tranel Adolphs 2003 Kensinger Brierley Medford Growdon Corkin 2002 Moreover the regions associated with emotional memory in young 1 Boston College 2Athinoula A Martinos Center for Biomedical Imaging 3Harvard University D 2008 Massachusetts Institute of Technology greatest during the successful encoding of positive information These valence specific processes are consistent with behavioral evidence that negative information is processed with perceptual detail whereas positive information is processed at a conceptual or schematic level The only age differences in emotional memory emerged during the successful encoding of positive items Older adults showed more activity in the medial prefrontal cortex and along the cingulate gyrus than young adults Because these regions often are associated with self referential processing these results suggest that older adults mnemonic boost for positive information may stem from an increased tendency to process this information in relation to themselves adults e g amygdala and orbito frontal cortex tend to be relatively preserved with aging both structurally Salat et al 2004 Salat Kaye Janowsky 2001 Chow Cummings 2000 Tisserand Visser van Boxtel Jolles 2000 and functionally Gutchess Kensinger Schacter 2007 Williams et al 2006 On the other hand however are studies that have suggested that the valence of information whether positive or negative may fundamentally influence the way in which older adults process and remember emotional information A number of studies have revealed a positivity shift with aging whereas young adults are more likely to remember negative information than positive or neutral information older adults may be at least as likely or even more likely to remember positive information compared with negative information Mather Carstensen 2005 It has been proposed that this positivity shift may occur because older adults put more emphasis on emotion regulation goals than do young adults with older adults having a greater motivation to derive emotional meaning from life and to maintain positive affect e g Mather Carstensen 2005 In the service of these goals older adults may focus their attention on things that will elicit pleasant feelings Mather 2006 Carstensen Isaacowitz Charles 1999 and may process positive information in a more self referential fashion Gutchess et al 2007 Although this argument has some empirical Journal of Cognitive Neuroscience 20 7 pp 1161 1173 support behavioral data do not always support the conclusion that older adults positivity shift results from changes in encoding processes For example when performing a digit parity task in which positive or negative distractor words were presented in between the two numbers that were to be evaluated older adults did not show a disproportionate interference effect from the positive words compared to the negative words Nevertheless the older adults did later remember the positive words better than the negative words Thomas Hasher 2006 These findings suggest that older adults positivity bias may not arise from increased attention toward positive items at the time of encoding However when older adults attentional resources are taxed during encoding by use of a divided attention manipulation their positivity effect disappears Mather Knight 2005 suggesting that there may be a link between the way in which older adults process positive versus negative at encoding that leads to their mnemonic benefit for positive information The present functional magnetic resonance imaging study used a subsequent memory paradigm in which encoding related activity to items of different valences was analyzed as a function of whether the items were later remembered or forgotten for more information on the use of the subsequent memory paradigm see review by Paller Wagner 2002 Thus the present study could examine whether there are age related changes in the neural processes supporting the successful encoding of emotional information and whether such changes could explain older adults positivity shift If age related changes in encoding processes correspond with the positivity shift then it should be possible to demonstrate age related changes in the neural processes that predict subsequent memory for positive information We therefore compared the neural processes that young and older adults recruited as they encoded positive negative and neutral information This design allowed us to examine subsequent memory effects that generalize to all emotional items i e positive and negative ones and also to uncover subsequent memory effects that are valence specific i e that correspond with

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