The role of the amygdala in emotional experience during retrieval of personal memories

ABSTRACT

Although the role of the amygdala in emotional memory retrieval has long been established, how such engagement varies depending on valence and retrieval context is less clearly understood. Participants retrieved personal memories associated with primarily positive, primarily negative, and mixed-valence images, pressing a button when successful. The button press divided trials into search and elaboration phases. Participants provided positivity and negativity ratings immediately following each trial, and then again in a post-retrieval survey. The relation between amygdala recruitment and emotionality exhibited a four-way interaction, with no other significant main effects or interactions. The interaction was driven by a temporal shift in the role of amygdala recruitment during retrieval of memories associated with mixed-valence images: Negativity ratings were supported more by search-related activity whereas positivity was more strongly associated with elaboration. Amygdala activity during retrieval relates to emotional experience in more complicated ways than previously understood. When participants were able to consider positive and negative aspects of the same event, amygdala recruitment during search and elaboration were associated with opposite behavioural effects. Such findings suggest that the amygdala may support distinct aspects of emotional experience for the same memory depending on when during retrieval it is recruited.     

The anger–distress model of temper tantrums: associations with emotional reactivity and emotional competence

The goals of this investigation were (a) to assess the structural validity of the anger–distress model of temper tantrums, and (b) to examine the associations among temper tantrums, emotional reactivity and emotional competence in a community sample of preschoolers. A parent‐report measure, the Temper Tantrum Grid, was used to measure the frequency of common tantrum behaviours. Laboratory and parent‐report measures of emotional reactivity and emotional competence were administered. Confirmatory factor analysis supported the proposal that anger and distress are separate but overlapping tantrum processes. Correlation analyses showed that temper tantrum anger and distress were related to emotional reactivity and emotional competence. There was no evidence to support the notion that emotional competence moderated the effect of emotional reactivity on temper tantrums. In contrast, emotional competence was a significant mediator of the association between emotional reactivity and temper tantrums. Overall, the results support the anger–distress model of temper tantrums. The findings suggest that children's temper tantrums are systematically related to the overall organization of emotion and behaviour in preschool children. Copyright © 2010 John Wiley & Sons, Ltd.     

The robustness of false memory for emotional pictures

Emotional material is commonly reported to be more accurately recognised; however, there is substantial evidence of increased false alarm rates (FAR) for emotional material and several reports of stronger influences on response bias than accuracy. This pattern is more frequently reported for words than pictures. Research on the mechanisms underlying bias differences has mostly focused on word lists under short retention intervals. This article presents four series of experiments examining recognition memory for emotional pictures while varying arousal and the control over the content of the pictures at two retention intervals, and one study measuring the relatedness of the series picture sets. Under the shorter retention interval, emotion increased false alarms and reduced accuracy. Under the longer retention interval emotion increased hit rates and FAR, resulting in reduced accuracy and/or bias. At both retention intervals, the pattern of valence effects differed based on the arousal associated with the picture sets. Emotional pictures were found to be more related than neutral pictures in each set; however, the influence of relatedness alone does not provide an adequate explanation for all emotional differences. The results demonstrate substantial emotional differences in picture recognition that vary based on valence, arousal and retention interval.     

Dysregulated negative emotional reactivity as a predictor of chronic peer victimization in childhood

This study examined the relations of dysregulated negative emotional reactivity, emotional distress, and chronic peer victimization in childhood. A model was proposed whereby dysregulated reactivity was directly and indirectly related to concurrent peer victimization through victimization‐related emotional distress. The model further proposed that dysregulated reactivity directly incrementally predicted longitudinal peer victimization above and beyond the effect of concurrent victimization. Two hundred thirteen 9‐ to 13‐year‐old children and their parents completed measures of dysregulated reactivity and victimization experiences at baseline and 6‐month follow‐up. Children also related narratives of personal victimization experiences at baseline that were coded to assess victimization‐related emotional distress. Model testing strongly supported the direct association of dysregulated reactivity with concurrent victimization and incremental predictive effects of dysregulated reactivity on peer victimization over time. Model testing also provided support for an indirect effect of dysregulated reactivity on concurrent peer victimization through victimization‐related emotional distress. This study demonstrated the powerful role that dysregulated negative emotional reactivity plays in the development of chronic peer victimization over time. Aggr. Behav. 38:414‐427, 2012. © 2012 Wiley Periodicals, Inc.     

Forget about the future: effects of thought suppression on memory for imaginary emotional episodes

Whether intentional suppression of an unpleasant or unwanted memory reduces the ability to recall that memory subsequently is a contested issue in contemporary memory research. Building on findings that similar processes are recruited when individuals remember the past and imagine the future, we measured the effects of thought suppression on memory for imagined future scenarios. Thought suppression reduced the ability to recall emotionally negative scenarios, but not those that were emotionally positive. This finding suggests that intentionally avoiding thoughts about emotionally negative episodes may inhibit representations of those memories, progressively reducing their availability to recall.     

Cognitive and emotional covariates of violence exposure among former prisoners: links to antisocial behavior and emotional distress and implications for theory

In this study, formerly incarcerated men (N = 123) were assessed for their experiences with violence in the community as well as their current behavioral and mental health status (antisocial behavior and emotional distress). Participants also completed measures of two constructs theorized to moderate relations between exposure to violence and outcomes: cognitive beliefs supporting aggressive responding and negative emotional reactivity to witnessed violence. Data on key social-demographic background factors affecting outcomes were also collected. Analyses showed that, after controlling the effects of background factors, relationships between experiences with violence in the community and behavioral/mental health were moderated by cognitive beliefs and emotional reactivity. At high levels of support for aggressive responding, significant positive links were observed between exposure to violence and antisocial behavior as well as emotional distress. At high levels of negative reactivity to violence, a significant positive link was observed between exposure to violence and emotional distress (but not antisocial behavior). Findings are discussed with respect to research and theory on the effects of exposure to violence in high-risk adult populations.     

The emotional carryover effect in memory for words

Emotional material rarely occurs in isolation; rather it is experienced in the spatial and temporal proximity of less emotional items. Some previous researchers have found that emotional stimuli impair memory for surrounding information, whereas others have reported evidence for memory facilitation. Researchers have not determined which types of emotional items or memory tests produce effects that carry over to surrounding items. Six experiments are reported that measured carryover from emotional words varying in arousal to temporally adjacent neutral words. Taboo, non-taboo emotional, and neutral words were compared using different stimulus onset asynchronies (SOAs), recognition and recall tests, and intentional and incidental memory instructions. Strong emotional memory effects were obtained in all six experiments. However, emotional items influenced memory for temporally adjacent words under limited conditions. Words following taboo words were more poorly remembered than words following neutral words when relatively short SOAs were employed. Words preceding taboo words were affected only when recall tests and relatively short retention intervals were used. These results suggest that increased attention to the emotional items sometimes produces emotional carryover effects; however, retrieval processes also contribute to retrograde amnesia and may extend the conditions under which anterograde amnesia is observed.     

A misleading feeling of happiness: metamemory for positive emotional and neutral pictures

Emotional information is often remembered better than neutral information, but the emotional benefit for positive information is less consistently observed than the benefit for negative information. The current study examined whether positive emotional pictures are recognised better than neutral pictures, and further examined whether participants can predict how emotion affects picture recognition. In two experiments, participants studied a mixed list of positive and neutral pictures, and made immediate judgements of learning (JOLs). JOLs for positive pictures were consistently higher than for neutral pictures. However, recognition performance displayed an inconsistent pattern. In Experiment 1, neutral pictures were more discriminable than positive pictures, but Experiment 2 found no difference in recognition based on emotional content. Despite participants’ beliefs, positive emotional content does not appear to consistently benefit picture memory.     

Effect of post-encoding emotion on recollection and familiarity for pictures

Although prior studies have examined the effect of post-encoding emotional arousal on recognition memory for words, it is unknown whether the enhancement effect observed on words generalizes to pictures. Furthermore, prior studies using words have showed that the effect of emotional arousal can be modulated by stimuli valence and delay in emotion induction, but it is unclear whether such modulation can extend to pictures and whether other factors such as encoding method (incidental vs. intentional encoding) can be modulatory. Five experiments were conducted to answer these questions. In Experiment 1, participants encoded a list of neutral and negative pictures and then watched a 3-min neutral or negative video. The delayed test showed that negative arousal impaired recollection regardless of picture valence but had no effect on familiarity. Experiment 2 replicated the above findings. Experiment 3 was similar to Experiment 1 except that participants watched a 3-min neutral, negative, or positive video and conducted free recall before the recognition test. Unlike the prior two experiments, the impairment effect of negative arousal disappeared. Experiment 4, where the free recall task was eliminated, replicated the results from Experiment 3. Experiment 5 replicated Experiments 1 and 2 and further showed that the impairment effects of negative arousal could be modulated by delay in emotion induction but not by encoding method or stimuli valence. Taken together, the current study suggests that the enhancement effect observed on words may not generalize to pictures.     

Effect of negative emotional pictures on associative memory for peripheral information

We investigated the influence of negative emotional pictures on associative memory. A visual object was embedded in the periphery of negative emotional or neutral pictures. Memory was assessed for central item (pictorial) information, peripheral (object) information, and the association between item and peripheral information. On tests of item information, negative emotional pictures were remembered better than neutral pictures. However, associative memory between item and peripheral information was less accurate when the pictures were negative compared to neutral. This occurred despite equivalent recall (Experiments 1 and 2) and recognition (Experiment 2) for the peripheral objects themselves. Further experiments confirmed that performance on the associative test was not influenced by testing order (Experiment 3). These findings suggest that negative emotional arousal can particularly disrupt the associative binding of peripheral information to a central emotional event.     

Effect of positive emotion on consolidation of memory for faces: The modulation of facial valence and facial gender

Studies have shown that emotion elicited after learning enhances memory consolidation. However, no prior studies have used facial photos as stimuli. This study examined the effect of post-learning positive emotion on consolidation of memory for faces. During the learning participants viewed neutral, positive, or negative faces. Then they were assigned to a condition in which they either watched a 9-minute positive video clip, or a 9-minute neutral video. Then 30 minutes after the learning participants took a surprise memory test, in which they made “remember”, “know”, and “new” judgements. The findings are: (1) Positive emotion enhanced consolidation of recognition for negative male faces, but impaired consolidation of recognition for negative female faces; (2) For males, recognition for negative faces was equivalent to that for positive faces; for females, recognition for negative faces was better than that for positive faces. Our study provides the important evidence that effect of post-learning emotion on memory consolidation can extend to facial stimuli and such an effect can be modulated by facial valence and facial gender. The findings may shed light on establishing models concerning the influence of emotion on memory consolidation.     

The effects of age and emotional valence on recognition memory: An ex‐Gaussian components analysis

The aim of this work was to study the effects of valence and age on visual image recognition memory. The International Affective Picture System (IAPS) battery was used, and response time data were analyzed using analysis of variance, as well as an ex‐Gaussian fit method. Older participants were slower and more variable in their reaction times. Response times were longer for negative valence pictures, however this was statistically significant only for young participants. This suggests that negative emotional valence has a strong effect on recognition memory in young but not in old participants. The τ parameter, often related to attention in the literature, was smaller for young than old participants in an ex‐Gaussian fit. Differences on the τ parameter might suggest poorer attentional performance in old participants.     

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.     

Effects of emotional content on working memory capacity

Emotional events tend to be remembered better than neutral events, but emotional states and stimuli may also interfere with cognitive processes that underlie memory performance. The current study investigated the effects of emotional content on working memory capacity (WMC), which involves both short term storage and executive attention control. We tested competing hypotheses in a preregistered experiment (N?=?297). The emotional enhancement hypothesis predicts that emotional stimuli attract attention and additional processing resources relative to neutral stimuli, thereby making it easier to encode and store emotional information in WMC. The emotional impairment hypothesis, by contrast, predicts that emotional stimuli interfere with attention control and the active maintenance of information in working memory. Participants completed a common measure of WMC (the operation span task; Turner, M. L., &; Engle, R. W. [1989]. Is working memory capacity task dependent? Journal of Memory and Language, 28, 127–154) that included either emotional or neutral words. Results revealed that WMC was reduced for emotional words relative to neutral words, consistent with the emotional impairment hypothesis.     

Distraction and reappraisal efficiency on immediate negative emotional responses: role of trait anxiety

Background and Objectives: Emotion regulation involves attempts to influence emotion unfolding and may target experiential, expressive and physiological responses. Several strategies can be used, such as reappraisal (re-evaluating the emotional situation to reduce its emotional meaning) or distraction (turning the attention toward non-emotional aspects of the situation). Previous research on these regulation strategies produced contrasting results regarding their efficiency and we hypothesize that this could be due to individual differences such as trait anxiety.

Design and Methods: Participants (N?=?77) were confronted with negative pictures and we examined the differential emotional reactivity according to trait anxiety, followed by a comparison of the efficiency of reappraisal and distraction in reducing emotional responses.

Results: Results show that trait anxiety has no impact on reactivity at the experiential and expressive levels, but has an impact at the physiological level, where high anxiety individuals show increased cardiac orienting effect, as well as higher skin conductance and respiratory rate. Regarding regulation, reappraisal and distraction successfully reduce emotional experience and expressivity, but not physiological arousal.

Conclusions: Such contrasting results involve that high trait anxiety individuals might benefit from the use of other kinds of strategies than reappraisal and distraction, some that may successfully target physiological responses.     

The role of memory for compounds in cue competition

Revisions of common associative learning models incorporate a within-compound association mechanism in order to explain retrospective cue competition effects (e.g., [Dickinson, A., & Burke, J. (1996). Within-compound associations mediate the retrospective revaluation of causality judgements. Quarterly Journal of Experimental Psychology, 49B, pp. 60-80.]). These models predict a correlation between memory for compounds (as a measure for the strength of within-compound associations) and retrospective cue competition but not forward cue competition. This was indeed found in a study of [Melchers, K. G., Lachnit, H., & Shanks, D. (2004). Within-compound associations in retrospective revaluation and in direct learning: A challenge for comparator theory. Quarterly Journal of Experimental Psychology, 57B, pp. 25-54.]. We argue that a higher-order reasoning account of causal learning can also explain the evidence for the role of within-compound associations in cue competition. Moreover, this account predicts that if making inferences during the learning stage is impeded, a correlation between memory for compounds and forward cue competition should be found as well. The results of a new study confirmed this prediction.     

The paradox of emotion attribution: explanation biases perceptual memory for emotional expressions

People who explain why ambiguous faces are expressing anger perceive and remember those faces as angrier than do people who explain why the same faces are expressing sadness. This phenomenon may be explained by a two-stage process in which language decomposes a facial configuration into its component features, which are then reintegrated with emotion categories available in the emotion explanation itself. This configural-decomposition hypothesis is consistent with experimental results showing that the explanation effect is attenuated when configural face processing is impaired (e.g., when the faces are inverted). Ironically, although people explain emotional expressions to make more accurate attributions, the process of explanation itself can decrease accuracy by leading to perceptual assimilation of the expressions to the emotions being explained.     

Age differences in perceptions of memory strategy effectiveness for recent and remote memory

We examined whether young and older adults hold different beliefs about the effectiveness of memory strategies for specific types of memory tasks and whether memory strategies are perceived to be differentially effective for young, middle-aged, and older targets. Participants rated the effectiveness of five memory strategies for 10 memory tasks at three target ages (20, 50, and 80 years old). Older adults did not strongly differentiate strategy effectiveness, viewing most strategies as similarly effective across memory tasks. Young adults held strategy-specific beliefs, endorsing external aids and physical health as more effective than a positive attitude or internal strategies, without substantial differentiation based on task. We also found differences in anticipated strategy effectiveness for targets of different ages. Older adults described cognitive and physical health strategies as more effective for older than middle-aged targets, whereas young adults expected these strategies to be equally effective for middle-aged and older target adults.     

Sex differences in aversive memory in rats: Possible role of extinction and reactive emotional factors

Studies usually show better spatial learning in males and stronger emotional memory in females. Spatial memory differences could relate to diverse strategies, while dissimilar stress reactions could cause emotional memory differences. We compared male and female rats in two emotional (classical emotional conditioning and aversive discrimination memory) and two emotionally “neutral” tasks: (1) plus-maze discriminative avoidance, containing two open and two enclosed arms, one of which presenting aversive stimuli (light/noise). No differences were found in learning, retrieving, or basal emotional levels, while only male rats presented extinction of the task; (2) contextual fear conditioning – a cage was paired to mild foot shocks. Upon reexposure, freezing behavior was decreased in females; (3) spontaneous alternation – the animals were expected to alternate among the arms of a four-arm maze. No differences between genders were found and (4) open-field habituation was addressed in an arena which the rats were allowed to explore for 10 min. Habituation was similar between genders. Differences were found only in tasks with strong emotional contexts, where different fear responses and stress effects could be determinant. The lack of extinction of discriminative avoidance by females points out to stronger consolidation and/or impaired extinction of aversive memories.