Post-encoding emotional arousal enhances consolidation of item memory,but not reality-monitoring source memory

The current study examined whether the effect of post-encoding emotional arousal on item memory extends to reality-monitoring source memory and, if so, whether the effect depends on emotionality of learning stimuli and testing format. In Experiment 1, participants encoded neutral words and imagined or viewed their corresponding object pictures. Then they watched a neutral, positive, or negative video. The 24-hour delayed test showed that emotional arousal had little effect on both item memory and reality-monitoring source memory. Experiment 2 was similar except that participants encoded neutral, positive, and negative words and imagined or viewed their corresponding object pictures. The results showed that positive and negative emotional arousal induced after encoding enhanced consolidation of item memory, but not reality-monitoring source memory, regardless of emotionality of learning stimuli. Experiment 3, identical to Experiment 2 except that participants were tested only on source memory for all the encoded items, still showed that post-encoding emotional arousal had little effect on consolidation of reality-monitoring source memory. Taken together, regardless of emotionality of learning stimuli and regardless of testing format of source memory (conjunction test vs. independent test), the facilitatory effect of post-encoding emotional arousal on item memory does not generalize to reality-monitoring source memory.     

情绪效价和唤醒对熟悉性和回想的不同影响

本研究检验了情绪的效价和唤醒对记忆提取阶段熟悉性过程和回想过程的影响及其心理机制。结果发现,编码阶段无分心任务时,积极图片的高、低自信再认准确率均高于消极图片,而唤醒对于高自信再认准确率的影响只限于消极图片;在编码阶段设置分心任务时,发现积极和消极的高唤醒图片的高自信再认准确率显著高于低唤醒图片。这些结果说明情绪的效价影响了熟悉性和回想两类记忆过程,而唤醒只影响回想过程,效价效应是编码阶段被试调用认知资源对积极图片进行精细加工的结果,而唤醒对回想过程的影响是自动编码高唤醒刺激细节的结果。     

情绪效价的记忆增强效应:存储或提取优势?

情绪效价和情绪唤醒是描述情绪的两个维度。情绪增强记忆效应表明情绪唤醒事件的记忆往往优于非情绪唤醒事件的记忆,但关于积极情绪记忆和消极情绪记忆哪个在记忆中处于优势仍存在争论。实验以情绪词对和中性词对为实验材料。实验一探讨积极情绪词语或消极情绪词语的记忆优势; 实验二探讨积极情绪环境或消极情绪环境中中性词语的记忆优势。在两种实验条件下,积极情绪下的自由回忆都优于消极情绪下的自由回忆; 多项加工树的存储—提取模型使用实验自由回忆和线索回忆的结果将记忆的存储和提取优势分离开来,结果表明:积极情绪事件记忆优势发生在存储阶段,而积极情绪环境记忆优势发生在存储和提取阶段; 积极情绪事件记忆偏向支持“刺激后编码增强假设”,积极情绪环境记忆偏向支持“唤醒—偏向竞争假设”。     

Time-limited effects of emotional arousal on item and source memory

Two experiments investigated the time-limited effects of emotional arousal on consolidation of item and source memory. In Experiment 1, participants memorized words (items) and the corresponding speakers (sources) and then took an immediate free recall test. Then they watched a neutral, positive, or negative video 5, 35, or 50?min after learning, and 24 hours later they took surprise memory tests. Experiment 2 was similar to Experiment 1 except that (a) a reality monitoring task was used; (b) elicitation delays of 5, 30, and 45?min were used; and (c) delayed memory tests were given 60?min after learning. Both experiments showed that, regardless of elicitation delay, emotional arousal did not enhance item recall memory. Second, both experiments showed that negative arousal enhanced delayed item recognition memory only at the medium elicitation delay, but not in the shorter or longer delays. Positive arousal enhanced performance only in Experiment 1. Third, regardless of elicitation delay, emotional arousal had little effect on source memory. These findings have implications for theories of emotion and memory, suggesting that emotion effects are contingent upon the nature of the memory task and elicitation delay.     

Immediate emotion-enhanced memory dependent on arousal and valence: The role of automatic and controlled processing

The phenomenon that emotional stimuli are better remembered than neutral ones is called emotion-enhanced memory (EEM). Previous studies have shown that both valence and arousal of stimuli contributed to EEM. Kensinger and Corkin (2004) proposed that the EEM dependent on arousal was associated with automatic encoding processes, whereas the EEM dependent on valence was associated with controlled encoding processes. Their experiment with negative words provided some evidence for this associative pattern. However, it is unclear whether the observed association that occurred with negative emotional stimuli could be replicated with positive emotional stimuli. To further examine this issue, two experiments were conducted to investigate the immediate EEM of emotional words in three different attention conditions using a divided attention (DA) paradigm. Results indicated that the immediate EEM dependent on valence was associated with controlled processing, while the immediate EEM dependent on arousal was not always associated with automatic processing. The immediate EEM dependent on arousal for negative stimuli was associated with automatic processing, whereas the immediate EEM dependent on arousal for positive stimuli was associated with controlled processing. Therefore, the immediate EEM dependent on arousal, whether it is associated with automatic or controlled processing, is moderated by the valence of stimuli.     

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.     

Timing matters: Negative emotion elicited 5 min but not 30 min or 45 min after learning enhances consolidation of internal-monitoring source memory

Two experiments examined the time-dependent effects of negative emotion on consolidation of item and internal-monitoring source memory. In Experiment 1, participants (n = 121) learned a list of words. They were asked to read aloud half of the words and to think about the remaining half. They were instructed to memorize each word and its associative cognitive operation (“reading” versus “thinking”). Immediately following learning they conducted free recall and then watched a 3-min either neutral or negative video clip when 5 min, 30 min or 45 min had elapsed after learning. Twenty-four hours later they returned to take surprise tests for item and source memory. Experiment 2 was similar to Experiment 1 except that participants, without conducting an immediate test of free recall, took tests of source memory for all encoded words both immediately and 24 h after learning. Experiment 1 showed that negative emotion enhanced consolidation of item memory (as measured by retention ratio of free recall) regardless of delay of emotion elicitation and that negative emotion enhanced consolidation of source memory when it was elicited at a 5 min delay but reduced consolidation of source memory when it was elicited at a 30 min delay; when elicited at a 45 min delay, negative emotion had little effect. Furthermore, Experiment 2 replicated the enhancement effect on source memory in the 5 min delay even when participants were tested on all the encoded words. The current study partially replicated prior studies on item memory and extends the literature by providing evidence for a time-dependent effect of negative emotion on consolidation of source memory based on internal monitoring.     

The effect of cognitive reappraisal on long‐term emotional experience and emotional memory

One's ability to properly regulate emotion is critical to psychological and physical well‐being. Among various strategies to regulate emotion, cognitive reappraisal has been shown to modulate both emotional experience and emotional memory. However, most studies of reappraisal have focused on reappraisal of negative situations, with reappraisal of positive emotion receiving considerably less attention. In addition, the effects of reappraisal on emotional reactions to stimuli are typically only assessed either immediately or after a short delay, and it remains unclear whether reappraisal effects persist over longer time periods. We investigated the effect of cognitive reappraisal on emotional reactions and long‐term episodic memory for positive and negative stimuli. Men and women viewed emotionally negative, positive, and neutral pictures while they were instructed to either increase, decrease, or maintain the initial emotional reactions elicited by the pictures. Subjective ratings of emotional valence and arousal were assessed during the regulation task and again after 1 week. Memory for the pictures was assessed with free recall. Results indicated that pictures accompanied by instructions to increase emotion were better recalled than pictures reappraised to decrease emotion. Modulation of emotional arousal elicited by stimuli persisted over a week, but this effect was observed only for men. These findings suggest that cognitive reappraisal can have long‐lasting effects on emotional reactions to stimuli. However, the sex differences observed for the effects of reappraisal on emotional reactions highlight the importance of considering individual differences in the effects of regulation.     

Memory enhancement for emotional words: Are emotional words more vividly remembered than neutral words?

Individuals are more likely to remember negative information than neutral information. In the experiments reported here, we examined whether individuals were also more likely to remember details of the presentation of negative words, as compared with neutral words. In Experiment 1, the remember-know procedure was used to examine the effect of emotion on the vividness of an individual's memory, showing that remember responses were more frequently assigned to negative words than neutral words. In Experiment 2, a source memory paradigm was used, and again, evidence that individuals' memories were more detailed for negative than for neutral words was found. In Experiments 3-6, we examined the relative contribution of valence and arousal, finding that both dimensions increased the vividness of remembered information (i.e., items with valence only and those that elicited arousal were better remembered than neutral information) but that the effect was greater for words that evoked arousal than for those with valence only. The results support a qualitative, as well as a quantitative, memory benefit for emotional, as compared with neutral, words.     

Event-related potentials of emotional memory: encoding pleasant,unpleasant, and neutral pictures

Emotional events tend to be remembered better than nonemotional events. We investigated this phenomenon by measuring two event-related potential (ERP) effects: the emotion effect (more positive ERPs for pleasant or unpleasant stimuli than for neutral stimuli) and the subsequent memory effect (more positive ERPs for subsequently remembered items than for subsequently forgotten items). ERPs were measured while subjects rated the emotional content of pleasant, unpleasant, and neutral pictures. As was expected, subsequent recall was better for pleasant and unpleasant pictures than for neutral pictures. The emotion effect was sensitive to arousal in parietal electrodes and to both arousal and valence in frontocentral electrodes. The subsequent memory effect at centroparietal electrodes was greater for emotional pictures than for neutral pictures during an early epoch (400-600 msec). This result suggests that emotional information has privileged access to processing resources, possibly leading to better memory formation.     

Do emotional stimuli interfere with response inhibition? Evidence from the stop signal paradigm

Participants performed a stop signal task in which an emotional picture preceded a neutral stimulus. They were asked to respond on the basis of the identity of the neutral stimulus unless an auditory tone was presented, in which case participants should try to withhold their response. In Experiment 1, we used positive, neutral and negative pictures. Results demonstrated that the presentation of an emotional stimulus prolonged both response and stopping latencies regardless of the valence of the emotional stimulus. This suggested that the degree of arousal could modulate the interference effect. In Experiment 2, high- and low-arousing pictures with a positive or negative valence were used. In line with the arousal hypothesis, high-arousal pictures interfered more with responding and stopping than low-arousing pictures whereas the valence of the pictures had little or no effect. These findings support the hypothesis that emotional stimuli interrupt ongoing cognitively controlled activities because they attract attention away from these ongoing activities.     

双加工再认提取中的情绪记忆增强效应

根据双加工理论, 再认提取可以划分为两种不同的加工：熟悉性与回想。以往的研究普遍认为情绪对再认提取具有增强效应, 但是情绪对再认记忆中两种不同加工方式(熟悉性与回想)的增强效应的神经机制尚存争议。本研究以ERP作为测量手段, 采用修正的“记得/知道”范式对情绪图片进行再认测验, 旨在探究在学习?测验间隔较长的条件下, 情绪信息如何对熟悉性与回想产生增强效应。在行为结果中, 对于知道判断, 情绪图片的记忆表现显著高于中性图片, 情绪效价间没有差异; 对于记得判断, 负性情绪图片的记忆表现要显著高于正性与中性图片。在ERP数据上, 对于知道判断, 情绪图片的FN400新旧效应有增强作用。对于记得判断, 负性图片的LPC的新旧效应波幅显著高于中性与负性图片; 而正性图片的LPC新旧效应增强作用不显著。以上证据表明：学习?测验间隔较长的情况下, 熟悉性再认提取中, 情绪记忆增强效应主要体现在情绪唤醒对记忆强度的提高, 而不仅仅体现在情绪效价对熟悉判断反应倾向的影响。在回想的再认提取中, 情绪效价的调节占据主导地位, 负性情绪图片有显著的情绪记忆增强效应; 正性情绪图片则不具有增强效应。     

Enhanced conflict-driven cognitive control by emotional arousal,not by valence

Emotion is widely agreed to have two dimensions, valence and arousal. Few studies have explored the effect of emotion on conflict adaptation by considering both of these, which could have dissociate influence. The present study aimed to fill the gap as to whether emotional valence and arousal would exert dissociable influence on conflict adaptation. In the experiments, we included positive, neutral, and negative conditions, with comparable arousal between positive and negative conditions. Both positive and negative conditions have higher arousal than neutral ones. In Experiment 1, by using a two-colour-word Flanker task, we found that conflict adaptation was enhanced in both positive and negative contexts compared to a neutral context. Furthermore, this effect still existed when controlling stimulus–response repetitions in Experiment 2, which used a four-colour-word Flanker task. The findings suggest emotional arousal enhances conflict adaptation, regardless of emotional valence. Thus, future studies should consider emotional arousal when studying the effect of emotion on conflict adaptation. Moreover, the unique role of the emotional context in conflict-driven cognitive control is emphasised.     

Gender differences in the effects of post-learning emotion on consolidation of item memory and source memory

Item memory and source memory are two integral elements of episodic memory. Although many studies have examined the effect of emotion on item memory, little research has simultaneously taken into account item memory and source memory. In addition, in the majority of previous studies, learning stimuli are used as the source of emotion, making it difficult to understand whether emotion has an effect on encoding or on consolidation of episodic memory. Furthermore, although gender differences exist in neurophysiological responses to emotional stimuli, in many studies gender differences were neglected and this leaves the picture incomplete regarding the effect of emotion on episodic memory. In this study, we examined gender differences in the effects of post-learning emotion on consolidation of item memory and source memory. Participants learned neutral Chinese nouns, took a memory pretest, and were then randomly assigned to three conditions, in which they either watched a 3-min negative video clip, or watched a 3-min positive video clip, or remained calm and relaxed for 3 min. Thirty minutes after the initial learning, participants took a memory posttest. We found that: (1) For females, post-learning negative emotion enhanced consolidation of item memory; however, neither negative emotion nor positive emotion had a significant effect on consolidation of source memory; (2) For males, neither negative nor positive emotion after learning had a significant effect on either item memory or source memory. Possible reasons for the gender differences, as well as the theoretical significance and practical implications of this study were discussed.     

Emotion processing effects on interference resolution in working memory

The interaction between emotion and working memory maintenance, load, and performance has been investigated with mixed results. The effect of emotion on specific executive processes such as interference resolution, however, remains relatively unexplored. In this series of studies, we examine how emotion affects interference resolution processes within working memory by modifying the Recency-probes paradigm (Monsel, 1978) to include emotional and neutral stimuli. Reaction time differences were compared between interference and non-interference trials for neutral and emotional words (Studies 1 & 3) and pictures (Study 2). Our results indicate that trials using emotional stimuli show a relative decrease in interference compared with trials using neutral stimuli, suggesting facilitation of interference resolution in the former. Furthermore, both valence and arousal seem to interact to produce this facilitation effect. These findings suggest that emotion facilitates response selection amid interference in working memory.     

回忆任务对合作抑制和错误修剪的调节——情绪效价和编码水平的影响

前人在项目回忆条件的合作记忆研究中记录到明显的合作抑制和错误修剪,背景提取条件的相关研究尤显不足;同时,情绪效价和编码水平对两类现象调节的研究尚未涉及。为此,本文在两个实验中采用经典合作记忆研究范式,以不同情绪效价的词汇为实验材料并以词汇在学习阶段的呈现颜色为背景展开研究。实验1和实验2分别在学习阶段采用了深编码和浅编码任务,回忆阶段则均含项目回忆(回忆已学词汇)和背景提取(回忆词汇在学习阶段的呈现颜色)两种任务。采用深编码条件的实验1的结果显示,项目回忆比背景提取条件的合作抑制更强、错误修剪更弱,回忆任务与词汇情绪效价交互影响合作抑制强度;采用浅编码条件的实验2则发现错误修剪在两种任务间的差异不显著。两实验的联合分析显示,回忆任务与编码水平交互影响合作抑制和错误修剪强度。上述结果表明:回忆任务对合作抑制和错误修剪的调节支持双重加工模型;回忆任务与情绪效价对合作抑制强度的交互影响支持权衡说,且与双重加工模型相吻合;回忆任务与编码水平交互影响合作抑制和错误修剪强度。     

Crossmodal transfer of arousal, but not pleasantness, from the musical to the visual domain

Arousal and valence (pleasantness) are considered primary dimensions of emotion. However, the degree to which these dimensions interact in emotional processing across sensory modalities is poorly understood. We addressed this issue by applying a crossmodal priming paradigm in which auditory primes (Romantic piano solo music) varying in arousal and/or pleasantness were sequentially paired with visual targets (IAPS pictures). In Experiment 1, the emotion spaces of 120 primes and 120 targets were explored separately in addition to the effects of musical training and gender. Thirty-two participants rated their felt pleasantness and arousal in response to primes and targets on equivalent rating scales as well as their familiarity with the stimuli. Musical training was associated with elevated familiarity ratings for high-arousing music and a trend for elevated arousal ratings, especially in response to unpleasant musical stimuli. Males reported higher arousal than females for pleasant visual stimuli. In Experiment 2, 40 nonmusicians rated their felt arousal and pleasantness in response to 20 visual targets after listening to 80 musical primes. Arousal associated with the musical primes modulated felt arousal in response to visual targets, yet no such transfer of pleasantness was observed between the two modalities. Experiment 3 sought to rule out the possibility of any order effect of the subjective ratings, and responses of 14 nonmusicians replicated results of Experiment 2. This study demonstrates the effectiveness of the crossmodal priming paradigm in basic research on musical emotions.     

Independent effects of word concreteness and word valence on immediate serial recall

The present study examined the roles of word concreteness and word valence in the immediate serial recall task. Emotion words (e.g. happy) were used to investigate these effects. Participants completed study-test trials with 7-item study lists consisting of positive or negative words with either high or low concreteness (Experiments 1 and 2) and neutral (i.e. non-emotion) words with either high or low concreteness (Experiment 2). In serial recall performance, we replicated the typical item concreteness effect (concrete words are better recalled than abstract words) and obtained an item valence effect (positive/neutral words are better recalled than negative words). However, there was no concreteness × valence interaction. We conclude that both word valence and word concreteness independently contribute to the serial order retention of emotion words in the immediate serial recall task.     

Emotion and memory: A recognition advantage for positive and negative words independent of arousal

Much evidence indicates that emotion enhances memory, but the precise effects of the two primary factors of arousal and valence remain at issue. Moreover, the current knowledge of emotional memory enhancement is based mostly on small samples of extremely emotive stimuli presented in unnaturally high proportions without adequate affective, lexical, and semantic controls. To investigate how emotion affects memory under conditions of natural variation, we tested whether arousal and valence predicted recognition memory for over 2500 words that were not sampled for their emotionality, and we controlled a large variety of lexical and semantic factors. Both negative and positive stimuli were remembered better than neutral stimuli, whether arousing or calming. Arousal failed to predict recognition memory, either independently or interactively with valence. Results support models that posit a facilitative role of valence in memory. This study also highlights the importance of stimulus controls and experimental designs in research on emotional memory.     

Vivid: How valence and arousal influence word processing under different task demands

In this study, we used event-related potentials to examine how different dimensions of emotion—valence and arousal—influence different stages of word processing under different task demands. In two experiments, two groups of participants viewed the same single emotional and neutral words while carrying out different tasks. In both experiments, valence (pleasant, unpleasant, and neutral) was fully crossed with arousal (high and low). We found that the task made a substantial contribution to how valence and arousal modulated the late positive complex (LPC), which is thought to reflect sustained evaluative processing (particularly of emotional stimuli). When participants performed a semantic categorization task in which emotion was not directly relevant to task performance, the LPC showed a larger amplitude for high-arousal than for low-arousal words, but no effect of valence. In contrast, when participants performed an overt valence categorization task, the LPC showed a large effect of valence (with unpleasant words eliciting the largest positivity), but no effect of arousal. These data show not only that valence and arousal act independently to influence word processing, but that their relative contributions to prolonged evaluative neural processes are strongly influenced by the situational demands (and by individual differences, as revealed in a subsequent analysis of subjective judgments).