Source of arousal and memory for detail

Two questions about the relationship between arousal and memory were investigated: First, does the source of arousal influence memory, and, second, what impact does arousal have on memory for detail? In Experiment 1, physiological arousal (running or not running in place) was factorially combined with emotional arousal (viewing a neutral or an emotional slide sequence). Recognition memory was tested for gist, central detail, and background detail. Experiments 2 and 3 were similar to Experiment 1, with the exception that a cued recall task was used in Experiment 2 and physiological arousal was manipulated with stationary biking in Experiment 3. The results of these experiments indicated that physiological arousal had little impact on memory and that emotional arousal led to improvements in memory for both central and background detail. Overall, these results supported the notions that the source of arousal is an important determinant of an event’s memorability (Christianson, 1992a) and that emotional arousal serves to enhance the scope of memory (i.e., flashbulb memory; Brown &; Kulik, 1977).     

Encoding details: positive emotion leads to memory broadening

In the current experiment we tested the hypothesis that unlike negative arousal, which leads to memory narrowing effects whereby an increase in memory for the central details is accompanied by a decrease in memory for the peripheral details, positive arousing events might lead to a memory broadening effect such that positive arousal would increase memory for both central and peripheral details. This was assessed by testing recognition for central and peripheral details of pictures that were selected to vary in a continuous manner across a wide range of arousal for both positive and negative items. The results indicated that increases in both positive and negative stimulus arousal levels led to gradual increases in memory for the central aspects of the photos. In contrast, negative arousal first increased then decreased memory for peripheral detail as arousal levels increased, whereas positive arousal led to a continuous increase in memory for peripheral details. Thus, arousing negative materials lead to memory narrowing, whereas arousing positive materials can lead to memory broadening.     

Encoding details: Positive emotion leads to memory broadening

In the current experiment we tested the hypothesis that unlike negative arousal, which leads to memory narrowing effects whereby an increase in memory for the central details is accompanied by a decrease in memory for the peripheral details, positive arousing events might lead to a memory broadening effect such that positive arousal would increase memory for both central and peripheral details. This was assessed by testing recognition for central and peripheral details of pictures that were selected to vary in a continuous manner across a wide range of arousal for both positive and negative items. The results indicated that increases in both positive and negative stimulus arousal levels led to gradual increases in memory for the central aspects of the photos. In contrast, negative arousal first increased then decreased memory for peripheral detail as arousal levels increased, whereas positive arousal led to a continuous increase in memory for peripheral details. Thus, arousing negative materials lead to memory narrowing, whereas arousing positive materials can lead to memory broadening.     

Sex-related impairment of memory for emotional events with beta-adrenergic blockade

On the basis of recent evidence indicating a sex-related lateralization of amygdala function in memory for emotional events, together with substantial evidence suggesting hemispheric specialization in processing global (central) versus local (detail) aspects of a situation, and the established dependence of the amygdala's memory modulating function on beta-adrenergic receptor activation, we predicted differential effects of a beta-adrenergic receptor antagonist (propranolol) on long-term memory for an emotionally arousing story in men and women. Specifically, we predicted that, relative to placebo, propranolol would impair memory for information central to the story line, but not memory for peripheral story details in men. Conversely, propranolol would impair memory for peripheral details, but not for central information in women. Here we confirm this prediction with a novel analysis of data from our two published studies of propranolol's effect on memory for an emotionally arousing story. These findings demonstrate a sex-related impairment of memory for emotional information by beta-adrenergic blockade. Additionally, they provide support for the hypothesis that, in this paradigm, emotional arousal enhances long-term memory for central information in men via activation of right amygdala/hemisphere function, and enhances long-term memory for peripheral details in women via activation of left amygdala/hemisphere function.     

Vivid memories of emotional events: The accuracy of remembered minutiae

It has been claimed that emotional arousal causes a narrowing of attention, and, therefore, impoverished memory encoding. On this view, if details of an emotional event are reported subsequently, these details must be after-the-fact reconstructions that are open to error. Our study challenges these claims. Using a long-term (2-week), incidental learning procedure, we found that emotion promotes memory both for information central to an event and for peripheral detail. This contrasts with the results of explicit instructions to remember or to attend closely to the event, both of which seem to promote memory for the event's gist at the expense of detail. The likely mechanisms underlying these effects are discussed.     

Effects of emotional arousal on memory binding in normal aging and Alzheimer's disease

Previous research suggests that associative memory declines in normal aging and is severely affected by Alzheimer's disease (AD); however, it is unclear whether and how this deficit can be minimized. The present study investigated whether emotional arousal improves associative memory in healthy younger and older adults and patients with probable AD. We examined the effect of arousal on memory for item-location associations. Arousal improved memory for item location similarly across the three groups, whereas valence had no effect in any groups. Overall, our results suggest that arousal has beneficial effects on associative memory in healthy older adults and patients with AD, as previously observed in younger adults.     

Hormonal contraception usage is associated with altered memory for an emotional story

Substantial evidence now documents sex-related influences on the neurobiology of emotional memory. Robust sex influences exist, for example, on the amygdala’s role in emotional memory formation, as well as on retention of central information (gist) and detail for an emotional event. Evidence also suggests that the well-documented effects of stress hormones on memory depend upon sex hormone levels. Since hormonal contraception alters sex hormone levels, and must by extension alter sex/stress hormone interactions in memory, we examined whether the use of hormonal contraception also alters memory for an emotional story. Two groups of healthy female subjects—one naturally cycling, one using hormonal contraception—viewed either a brief, emotionally arousing story, or a closely matched, but more emotionally neutral story. Each subject’s eye movements and pupil dilation changes were recorded as they viewed the story. Additionally, saliva samples were taken throughout the experimental session to examine salivary alpha-amylase, a biomarker for norepinephrine. A surprise free recall test one week later measured story memory in all subjects. Naturally cycling women exhibited enhanced memory of story details, but not of central information (gist), in the emotional compared with neutral story conditions. In contrast, women using hormonal contraception exhibited enhanced memory of gist, but not story details, in the emotional compared with neutral story conditions. Analysis of eye movements made while watching the stories indicated that the differences in memory could not be attributed either to a differential attention focus or to the degree of arousal induced by the stories in the two groups. These findings suggest that the use of hormonal contraception alters memory for an emotional event, perhaps by altering sex/stress hormone interactions in memory formation. They also suggest that further investigation of the mnemonic effects of these very widely used treatments is warranted.     

The effects of emotion on younger and older adults’ monitoring of learning

Age-related differences in memory monitoring appear when people learn emotional words. Namely, younger adults’ judgments of learning (JOLs) are higher for positive than neutral words, whereas older adults’ JOLs do not discriminate between positive versus neutral words. In two experiments, we evaluated whether this age-related difference extends to learning positive versus neutral pictures. We also evaluated the contribution of two dimensions of emotion that may impact younger and older adults’ JOLs: valence and arousal. Younger and older adults studied pictures that were positive or neutral and either high or low in arousal. Participants made immediate JOLs and completed memory tests. In both experiments, the magnitude of older adults’ JOLs was influenced by emotion, and both younger and older adults demonstrated an emotional salience effect on JOLs. As important, the magnitude of participants’ JOLs was influenced by valence, and not arousal. Emotional salience effects were also evident on participants’ free recall, and older adults recalled as many pictures as did younger adults. Taken together, these data suggest that older adults do not have a monitoring deficit when learning positive (vs. neutral) pictures and that emotional salience effects on younger and older adults’ JOLs are produced more by valence than by arousal.     

简化的联合再认范式中情绪对错误记忆影响的年龄差异

以康奈尔情绪DRM词表为主要实验材料, 使用简化的联合再认范式(DRM范式的变式), 结合多项式加工树建模的统计手段, 对34名年轻人(23 ± 2岁)和28名老年人(68 ± 5岁)的再认记忆进行比较, 以考察不同年龄组中情绪效价对错误记忆的作用机制。结果发现材料的情绪效价对错误记忆的影响存在显著年龄差异：(1) 积极情绪能够有效降低老年人的错误记忆, 其作用机制为积极情绪增强了老年人的字面痕迹而减弱了要点痕迹提取; (2) 消极情绪能够有效地降低年轻人的错误记忆, 其作用机制为消极情绪使年轻人反应偏向降低, 但不影响其记忆痕迹的提取。结果表明, 简化的联合再认范式下, 情绪效价对错误记忆的效应存在明显的年龄差异：老年人表现出积极情绪降低错误记忆的积极偏向; 年轻人表现出消极情绪降低错误记忆的消极偏向; 情绪效应对错误记忆的认知机制存在年龄差异。     

The influence of sex versus sex-related traits on long-term memory for gist and detail from an emotional story

Recent findings demonstrate sex-related differences in the neurobiological mechanisms by which emotional arousal influences memory, and raise questions about the extent to which memory for emotional events may differ between males and females. Here we examine whether sex-related differences exist in the recall of central (gist) information and peripheral detail from an emotional story. Healthy subjects viewed a brief, narrated slide-show containing emotional elements in its middle section. One week later, they received an incidental multiple-choice recognition test for the story. Following the test, each subject completed the BEM Sex-Role Inventory, an assessment of sex-related masculine and feminine traits. The results reveal no differences in recall of either central or peripheral story information when considering the performance of actual men and women, but a significant difference when considering male and females as determined by their BEM test scores. "BEM" males (subjects with net male BEM scores) showed significantly enhanced recall of central emotional information. "BEM" females did not. Both groups showed significantly enhanced recall of peripheral emotional information, although this effect appeared larger in BEM females than in BEM males. The influences of "BEM" sex and type of information (central, peripheral) significantly interacted to influence emotional memory performance. These findings confirm the existence of sex-related influences in the recall of emotional information, and suggest that sex-related traits, rather than actual sex per se, may be a more sensitive indicator of these influences.     

Emotional arousal and memory: a test of the poststimulus processing hypothesis

Emotional arousal is believed to enhance memory for details central to an episode but impair memory for peripheral details. However, new research suggests that arousal induced thematically (i.e., through involvement with an unfolding event) produces only memory enhancements. This article examines whether consciously controlled elaborative processing in the aftermath of an arousing experience is responsible. A dual task manipulation was used to prevent participants from ruminating over a video that depicted an abduction and attack. Several indices of recall showed greater memory for emotional event details than for details from a neutral control video, which remained the case when the opportunity for post-stimulus elaboration was prevented. Thus, superior retention of the content of emotional experiences may arise from the way in which arousal is induced rather than through immediate postevent cognitions.     

Emotional organization of autobiographical memory

The emotional organization of autobiographical memory was examined by determining whether emotional cues would influence autobiographical retrieval in younger and older adults. Unfamiliar musical cues that represented orthogonal combinations of positive and negative valence and high and low arousal were used. Whereas cue valence influenced the valence of the retrieved memories, cue arousal did not affect arousal ratings. However, high-arousal cues were associated with reduced response latencies. A significant bias to report positive memories was observed, especially for the older adults, but neither the distribution of memories across the life span nor response latencies varied across memories differing in valence or arousal. These data indicate that emotional information can serve as effective cues for autobiographical memories and that autobiographical memories are organized in terms of emotional valence but not emotional arousal. Thus, current theories of autobiographical memory must be expanded to include emotional valence as a primary dimension of organization.     

Enhanced selective memory consolidation following post-learning pleasant and aversive arousal

It is well established that emotions modulate memory, typically enhancing consolidation through post-learning arousal. However, many aspects of this phenomenon have yet to be delineated. For example, it remains unclear whether or not the type of arousal is relevant (pleasant vs. aversive), whether arousal enhances memory selectively for some stimuli but not others (emotional vs. neutral), which specific aspects of the stimulus representation (gist vs. detail) are affected, and whether these mechanisms are sexually dimorphic. In order to explore these issues, 178 undergraduate participants viewed a series of negative, positive and neutral pictures. They were then subjected to a post-learning arousal manipulation in the form of a pleasantly arousing-, aversively arousing-, or neutral video. Free recall tests one week later indicated that both pleasant and aversive post-learning arousal enhanced memory consolidation for positive and negative but not neutral stimuli, independent of the participants' sex. Further analysis for gist and detail aspects suggests that post-learning arousal enhances memory for the gist of the stimuli. The study has implications for the understanding of healthy and pathological cognitive-affective processes in humans.     

The effects of emotional arousal and gender on the associative memory deficit of older adults

In this study we assessed the potential moderating roles of stimulus type (emotionally arousing) and participants’ characteristics (gender) in older adults’ associative memory deficit. In two experiments, young and older participants studied lists that included neutral and emotionally arousing word pairs (positive and negative) and completed recognition tests for the words and their associations. In Experiment 1, the majority of the word pairs were composed of two nouns, whereas in Experiment 2 they were composed of adjective–noun pairs. The results extend evidence for older adults’ associative deficit and suggest that older and younger adults’ item memory is improved for emotionally arousing words. However, associative memory for the word pairs did not benefit (and even showed a slight decline) from emotionally arousing words, which was the case for both younger and older adults. In addition, in these experiments, gender appeared to moderate the associative deficit of older adults, with older males but not females demonstrating this deficit.     

Reality monitoring and memory distortion: Effects of negative, arousing content

Although individuals often claim to vividly remember negatively arousing information, few studies have been performed to examine whether this emotional information is remembered more accurately than nonemotional information. In the present study, we investigated whether the emotional content of items modulates the accuracy with which individuals make reality-monitoring decisions. Participants (young adults, 18-35 years of age) distinguished imagined from seen words (Experiments 1 and 3A) or objects (Experiments 2 and 3B). Half of the items studied in each condition (presented and imagined) were negative and arousing, and half were neutral. The participants mistook imagined items for presented ones, but the number of reality-monitoring errors was lower for the arousing items than for the neutral items. Negative, arousing items appear to be remembered with contextual detail more frequently than are neutral items, leading memory for this emotional information to be less prone to distortion than is memory for neutral information. Thus, negative arousal can enhance not only the subjective vividness of a memory, but also a memory's accuracy.     

Eyewitness memory for arousing events: putting things into context

If attention is focused on central details at high levels of arousal, memory for peripheral details should be diminished (Easterbrook, 1959 ). If this is the case, contextual reinstatement (CR) procedures should not enhance memory because these procedures specifically use peripheral information to cue memory. The present experiment tested how arousal influenced eyewitness memory for an event and how it interacts with CR procedures. Participants first viewed one of three series of slides (neutral, arousal, or unusual/control). Memory for central and peripheral details was tested via photo lineups and recognition tests. Although CR procedures enhanced recognition memory for non‐arousing and unusual events, they did not affect recognition memory for arousing events. Analyses of the peripheral photo lineup and peripheral recognition test data revealed that CR enhanced the hit rate for the neutral and unusual conditions but not for the arousal condition. Although CR procedures tended to enhance recognition of central information (increasing the hit rate and decreasing the false alarm rate), CR had a smaller enhancement effect in the arousal condition relative to the neutral and unusual conditions. The present experiment also replicates the Christianson and Loftus ( 1991 ) finding that peripheral information is not remembered as well in an arousing event, as compared to memory of neutral and unusual events. The theoretical and applied implications of these results are discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

Emotionally arousing pictures increase blood glucose levels and enhance recall

Arousal enhances memory in human participants and this enhancing effect is likely due to the release of peripheral epinephrine. As epinephrine does not readily enter the brain, one way that peripheral epinephrine may enhance memory is by increasing circulating blood glucose levels. The present study investigated the possibility that emotionally arousing color pictures would improve memory and elevate blood glucose levels in human participants. Blood glucose levels were measured before, 15 min, and 30 min after male university students viewed 60 emotionally arousing or relatively neutral pictures. Participants viewed each picture for 6 s and then had 10 s to rate the arousal (emotional intensity) and valence (pleasantness) of each picture. A free-recall memory test was given 30 min after the last picture was viewed. Although the emotionally arousing and neutral picture sets were given comparable valence ratings, participants who viewed the emotionally arousing pictures rated the pictures as being more arousing, recalled more pictures, and had higher blood glucose levels after viewing the pictures than did participants who viewed the neutral pictures. These findings indicate that emotionally arousing pictures increase blood glucose levels and enhance memory, and that this effect is not due to differences in the degree of pleasantness of the stimuli. These findings support the possibility that increases in circulating blood glucose levels in response to emotional arousal may be part of the biological mechanism that allows emotional arousal to enhance memory.     

Effects of aging and encoding instructions on emotion-induced memory trade-offs

The effects of emotion on memory are often described in terms of trade-offs: People often remember central, emotional information at the expense of background details. The present experiment examined the effects of aging and encoding instructions on participants' ability to remember the details of central emotional objects and the backgrounds on which those objects were placed. When young and older adults passively viewed scenes, both age groups showed strong emotion-induced trade-offs. They were able to remember the visual details as well as the general theme of the emotional object, but they had difficulties remembering the visual specifics of the scene background. Age differences emerged, however, when participants were given encoding instructions that emphasized elaborative encoding of the entire scene. With these instructions, young adults overcame the trade-offs (i.e., they no longer showed impairing effects of emotion), whereas older adults continued to show good memory for the emotional object but poor memory for its background. These results suggest that aging impairs the ability to flexibly disengage attention from the negative arousing elements of scenes, preventing the successful encoding of nonemotional aspects of the environment.     

The effect of ageing on the recollection of emotional and neutral pictures

This study investigated age-related differences in recognition memory for emotional and neutral pictures. Younger and older participants were asked to rate pictures according to their emotional valence, arousal, and visual complexity. Two weeks later they had to recognise these pictures and the states of awareness associated with memory were assessed with the "remember/know/guess" paradigm. We found that, although the influence of emotion on recognition accuracy (as assessed by d') was similar in both age groups, the tendency for positive and negative pictures to create a rich recollective experience was weaker in older adults. In addition, "remember" responses were more often based on a recollection of emotional reactions in older than in younger participants. We suggest that the elderly tend to focus on their feelings when confronted with emotional pictures, which could have impaired their memory for the contextual information associated with these stimuli.     

The effect of ageing on the recollection of emotional and neutral pictures

This study investigated age-related differences in recognition memory for emotional and neutral pictures. Younger and older participants were asked to rate pictures according to their emotional valence, arousal, and visual complexity. Two weeks later they had to recognise these pictures and the states of awareness associated with memory were assessed with the “remember/know/guess” paradigm. We found that, although the influence of emotion on recognition accuracy (as assessed by d′) was similar in both age groups, the tendency for positive and negative pictures to create a rich recollective experience was weaker in older adults. In addition, “remember” responses were more often based on a recollection of emotional reactions in older than in younger participants. We suggest that the elderly tend to focus on their feelings when confronted with emotional pictures, which could have impaired their memory for the contextual information associated with these stimuli.