Age-related Difference In Negative Memory Enhancement Effect In Dual-processing Recognition Retrieval

Since the 21 st century,China’s aging population is becoming larger and larger,which poses a challenging problem for the society.Episodic memory has attracted extensive attention in the field of cognitive aging because it is most closely related to daily life and most affected by aging.With age,the episodic memory of older adults has showed an obvious trend of declining,but emotional memory is largely unaffected,which shows the asymmetric nature of memory decline.It is established that negative emotions can enhance young people’s episodic memory processing,which is also known as the negativity bias in attention and memory.However,studies of older adults have found mixed results.The present study focused on the moderating role of aging in the negative emotional enhancement of memory effects during recollection-base and familiarity-based retrieval,and explored the effect of negative emotions on attention in older adults from the perspective of eye movement behavior,so as to reveal the mechanism of the enhanced negative emotional memory in older adults.The present study has its basis on the national needs of healthy aging and also has important reference significance to alleviate depression or anxiety in older adults.The present study used the canonical R/K paradigm and eyetracker to investigate the agerelated difference in the enhanced negative emotional memory during recollection-base and familiarity-based retrieval after intentional encoding when arousals of emotional stimuli were kept at a moderate level.For behavioral data,with hit rate,false alarm rate,and discrimination as dependent variables respectively,a three-way repeated-measures ANOVA were conducted,with age group(old vs.young),emotion valence(negative vs.neutral),and response type(remember vs.know)as independent variables,to explore whether negative emotions would also enhance older adults’ memory.And if so,is it more related to recollection-based retrieval or familiarity-based retrieval? For eye movement data,with the number of fixations,relative visual attention entropy(r VAE),and relative RMSD values from both encoding and retrieval as dependent variables respectively,linear mixed effect models were fitted with age group,emotional valence,and response type as fixed effects,and with subjects and/or emotional stimuli as random effects to account for individual differences in gaze patterns between subjects and/or between emotional stimuli,so as to explore how negative emotions affect attention in young and older adults during encoding and retrieval.Similar analysis was also done for gaze reinstatement,which measures the spatial overlap between patterns of fixations corresponding to the same image viewed by the same participant during encoding and retrieval while controlling for image-invariant(idiosyncratic)viewing biases(e.g.,center bias),so as to learn age-related difference in the effect of negative emotions on encoding-retrieval similarity of scanpath or memory reinstatement.The results showed that:(1)In terms of behavioral data,for both young and older adults,in the “remember” response,discriminations of negative stimuli were significantly higher than that of neutral stimuli,but in the “know” response,discriminations of negative stimuli were significantly lower than that of neutral stimuli;(2)In terms of eye movement data,for both young and older adults,the pattern of results was shared between encoding and retrieval.That is,fixation counts of negative emotional stimuli was significantly larger than that of neutral stimuli,showing an attentional bias towards negative stimuli;Nonetheless,relative to young adults,in older adults the effect of negative emotions on gaze reinstatement was significantly greater than that of neutral emotions.That is,negative emotions could enhance gaze reinstatement in older adults.In the present study,negative emotional memory enhancement was also found in the recollection-based retrieval in older adults,and eye movement evidence suggests that it may be accounted for by the finding that negative emotions enhanced memory recapitulation of older adults.This study has certain theoretical value and practical significance for understanding the effect of negative emotions on older adults’ attention and memory,and provides direct evidence for the accounts of NEVER(Negative Emotional Valence Enhances Recapitulation).