Generation and memory for contextual detail

Generation enhances item memory but may not enhance other aspects of memory. In 12 experiments, the author investigated the effect of generation on context memory, motivated in part by the hypothesis that generation produces a trade-off in encoding item and contextual information. Participants generated some study words (e.g., hot-c__) and read others (e.g., hot-cold). Generation consistently enhanced item memory but did not enhance context memory. More specifically, generation disrupted context memory for the color of the target word but did not affect context memory for location, background color, and cue-word color. The specificity of the negative generation effect in context memory argues against a general item-context trade-off. A processing account of generation meets greater success. In addition, the results provide no evidence that generation enhances recollection of contextual details.     

Arousal,valence, and memory for detail

A common finding in the emotion‐memory literature is that memory is enhanced for positively arousing stimuli and negatively arousing stimuli relative to neutral stimuli. We tested the notion that post‐stimulus elaboration is responsible for these effects. Post‐stimulus elaboration refers to the process of thinking about an event (after its offset) more frequently or more in‐depth. We tested the hypothesis by presenting participants with 36 slides depicting events that varied in arousal (low and high) and valence (positive and negative). The opportunity for elaboration was manipulated by requiring participants, during the inter‐slide interval, to complete addition problems, simply view the addition problems, or view a blank slide. Cued recall memory was tested for central and background details. Based on the post‐stimulus elaboration hypothesis it was expected that the greatest memory decline would occur for the central details of negatively and positively arousing slides when participants were required to complete addition problems (i.e., a distractor task × arousal × detail interaction). Contrary to the hypothesis, we found that filling the inter‐slide interval with a distractor task decreased memory for negative stimuli compared to positive stimuli. This effect was independent of arousal. We also found that arousal increased central detail memory for positive and negative stimuli and background detail memory for positive stimuli but not for negative stimuli. This interaction was explained on the basis of pre‐attentive encoding and cue utilisation. It was concluded that in order to understand the complex relationship between emotion and memory, future studies should include, as a minimum, the variables of valence, arousal, and detail.     

Arousal, valence, and memory for detail

A common finding in the emotion-memory literature is that memory is enhanced for positively arousing stimuli and negatively arousing stimuli relative to neutral stimuli. We tested the notion that post-stimulus elaboration is responsible for these effects. Post-stimulus elaboration refers to the process of thinking about an event (after its offset) more frequently or more in-depth. We tested the hypothesis by presenting participants with 36 slides depicting events that varied in arousal (low and high) and valence (positive and negative). The opportunity for elaboration was manipulated by requiring participants, during the interslide interval, to complete addition problems, simply view the addition problems, or view a blank slide. Cued recall memory was tested for central and background details. Based on the post-stimulus elaboration hypothesis it was expected that the greatest memory decline would occur for the central details of negatively and positively arousing slides when participants were required to complete addition problems (i.e., a distractor task x arousal x detail interaction). Contrary to the hypothesis, we found that filling the inter-slide interval with a distractor task decreased memory for negative stimuli compared to positive stimuli. This effect was independent of arousal. We also found that arousal increased central detail memory for positive and negative stimuli and background detail memory for positive stimuli but not for negative stimuli. This interaction was explained on the basis of pre-attentive encoding and cue utilisation. It was concluded that in order to understand the complex relationship between emotion and memory, future studies should include, as a minimum, the variables of valence, arousal, and detail.     

The role of arousal in memory for conversation

In the first experimental study of memory for natural conversation, Keenan, MacWhinney, and Mayhew (1977) found that, even after 30 h, subjects had extremely good recognition memory for the exact wording of statements that contained information about a speaker’s “intentions, beliefs, and his relations with the listener.” Such sentences were said to be high in “interactionai content.” One possible interpretation of the results of Keenan et al. is that it is the immediate affective response to an utterance, rather than its interactional content, that increases its memorability. In the present study, the strong relationship between interactional content and memory found by Keenan et al. was replicated. Subjects showed excellent recognition memory for high interactional content statements from a conversation, even after a 72-h interval. However, there was very little relationship between arousal, as determined by subjects’ electrodermal response (EDR), and subsequent memory. Moreover, involvement had its greatest effect not on memory, but on subjects’ arousal as measured by EDR.     

Non-monotonic relationships between emotional arousal and memory for color and location

Recent research points to the decreased diagnostic value of subjective retrieval experience for memory accuracy for emotional stimuli. While for neutral stimuli rich recollective experiences are associated with better context memory than merely familiar memories this association appears questionable for emotional stimuli. The present research tested the implicit assumption that the effect of emotional arousal on memory is monotonic, that is, steadily increasing (or decreasing) with increasing arousal. In two experiments emotional arousal was manipulated in three steps using emotional pictures and subjective retrieval experience as well as context memory were assessed. The results show an inverted U-shape relationship between arousal and recognition memory but for context memory and retrieval experience the relationship was more complex. For frame colour, context memory decreased linearly while for spatial location it followed the inverted U-shape function. The complex, non-monotonic relationships between arousal and memory are discussed as possible explanations for earlier divergent findings.     

Cortisol and stimulus-induced arousal level differentially impact memory for items and backgrounds

Most studies examine the effects of stress on memory for visual information test memory for entire scenes. However, arousal levels may differentially influence memory for backgrounds as opposed to items. Participants encoded scenes that included a negative-high-arousal, negative-moderate-arousal, or neutral item on a neutral background. After a 30-minute (Experiment 1) or 48-hour delay (Experiment 2), participants underwent a stressor or control task while heart rate was recorded. A recognition memory task was then given with items and backgrounds presented separately. High-arousal images had a greater detriment in background memory than moderate-arousal images. Further, though there was evidence that change in cortisol level at retrieval was associated with impaired memory for items, it was not associated with detriments in background memory. Increased heart rate was associated with impaired memory for both items and backgrounds. This suggests that the level of sympathetic and cortisol reactivity differentially affects memory for items and backgrounds.     

Source memory enhancement for emotional words

The influence of emotional stimuli on source memory was investigated by using emotionally valenced words. The words were colored blue or yellow (Experiment 1) or surrounded by a blue or yellow frame (Experiment 2). Participants were asked to associate the words with the colors. In both experiments, emotionally valenced words elicited enhanced free recall compared with nonvalenced words; however, recognition memory was not affected. Source memory for the associated color was also enhanced for emotional words, suggesting that even memory for contextual information is benefited by emotional stimuli. This effect was not due to the ease of semantic clustering of emotional words because semantically related words were not associated with enhanced source memory, despite enhanced recall (Experiment 3). It is suggested that enhancement resulted from facilitated arousal or attention, which may act to increase organization processes important for source memory.     

Remembering pictures: pleasure and arousal in memory.

Incidental memory performance for pictures that varied along the affective dimensions of pleasantness and arousal was assessed. For both an immediate and delayed (1 year later) free-recall task, only the arousal dimension had a stable effect on memory performance: Pictures rated as highly arousing were remembered better than low-arousal stimuli. This effect was corroborated in a speeded recognition test, in which high-arousal materials encoded earlier in the experiment produced faster reaction times than their low-arousal counterparts. Pleasantness affected reaction time decisions only for pictures not encoded earlier. These results suggest that whereas both the dimensions of pleasantness and arousal are processed at initial encoding, long-term memory performance is mainly affected by arousal.     

Sensation seeking, recognition memory, and autonomic arousal

Substantial evidence shows that sensation seeking impacts memory; however, research has not examined how sensation seeking impacts automatic familiarity and conscious-controlled recollection memory systems. The present study (N = 80) examined high and low sensation seekers’ familiarity and recollection of high and low arousal images with negative valence using behavioral and skin conductance measures. Low sensation seekers had more accurate familiarity judgments to high than low arousal images, reflecting a heightened aversive motivational system. High sensation seekers showed an opposite pattern with memory enhancement for low arousal images, regardless of old-new status. The lack of any sensation seeking effects in relation to recollection judgments suggests that this personality trait is more influential on automatic than conscious controlled memory systems.     

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.     

Emotional valence and arousal effects on memory and hemispheric asymmetries

This study examined predictions based upon the right hemisphere (RH) model, the valence–arousal model, and a recently proposed integrated model (Killgore & Yurgelun-Todd, 2007) of emotion processing by testing immediate recall and recognition memory for positive, negative, and neutral verbal stimuli among 35 right-handed women. Building upon methodologies of previous studies, we found that words presented to the right visual field/left hemisphere (RVF/LH) were recalled and recognized more accurately than words presented to the left visual field/right hemisphere (LVF/RH), and we found significant valence by visual field interactions. Some findings were consistent with one of the models evaluated whereas others were consistent with none of the models evaluated. Our findings suggest that an integration of the RH and valence–arousal models may best account for the findings with regard to hemispheric lateralization of memory for emotional stimuli.     

情绪唤醒影响记忆巩固过程的神经生理机制

白鼠和人类都对情绪唤醒的经历有更好的记忆。情绪唤醒影响记忆巩固的神经生理机制主要有以下几种方式:(a)情绪唤醒或急性应激,会引发个体内部应激激素的释放,从而增强其记忆巩固过程。(b1)杏仁核的激活对情绪唤醒影响记忆巩固过程十分重要,杏仁核内部去甲肾上腺素(NE)的释放影响记忆巩固过程。(b2)杏仁核投射到负责不同类型记忆加工的脑区,如海马和皮层,从而影响记忆。(c)应激激素影响记忆巩固的过程中,杏仁核内NE的激活在这一过程中扮演着重要角色。综上,情绪唤醒影响记忆巩固的过程,涉及到激素调节、神经调节及二者的共同作用。     

Comparing two perceived characteristics of autobiographical memory: Memory detail and accessibility

Four samples of participants recalled autobiographical memories. While some evidence emerged from regression analyses suggesting that judgements of the amount of detail contained in each memory and judgements of the ease with which events could be recalled were partially independent, the analyses generally showed that these judgements were similarly predicted by various event characteristics (age, typicality, self-importance, emotional intensity at event occurrence, rehearsal types). Co-occurrence frequency data yielded similar conclusions, showing that while ease ratings and detail ratings occasionally diverged, they were more often consistent with each other. Finally, the data also suggested that events that prompted emotional ambivalence were not judged to be more easily recalled, or to contain more detail, than non-ambivalent events.     

Comparing two perceived characteristics of autobiographical memory: Memory detail and accessibility

Four samples of participants recalled autobiographical memories. While some evidence emerged from regression analyses suggesting that judgements of the amount of detail contained in each memory and judgements of the ease with which events could be recalled were partially independent, the analyses generally showed that these judgements were similarly predicted by various event characteristics (age, typicality, self-importance, emotional intensity at event occurrence, rehearsal types). Co-occurrence frequency data yielded similar conclusions, showing that while ease ratings and detail ratings occasionally diverged, they were more often consistent with each other. Finally, the data also suggested that events that prompted emotional ambivalence were not judged to be more easily recalled, or to contain more detail, than non-ambivalent events.     

The moderating role of arousal on the seductive detail effect in a multimedia learning setting

Arousal has been found to increase learners' attentional resources. In contrast, seductive details (interesting but learning‐irrelevant information) are considered to distract attention away from relevant information and, thus, hinder learning. However, a possibly moderating role of arousal on the seductive detail effect has not been examined yet. In this study, arousal variations were induced via audio files of false heartbeats. In consequence, 100 participants were randomly assigned to a 2 (with or without seductive details) × 2 (lower vs. higher false heart rates) between‐subjects design. Data on learning performance, cognitive load, motivation, heartbeat frequency, and electro‐dermal activity were collected. Results show learning‐inhibiting effects for seductive details and learning‐enhancing effects for higher false heart rates. Cognitive processes mediate both effects. However, the detrimental effect of seductive details was not present when heart rate was higher. Results indicate that the seductive detail effect is moderated by a learner's state of arousal.     

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.     

Effect of arousal and retention delay on memory: a meta-analysis

Two meta-analyses were conducted to examine the magnitude of the interaction between arousal and retention delay on various types of memory, e.g., verbal, visual, etc., as initially reported by Kleinsmith and Kaplan in 1963 and 1964. Results of the first meta-analysis (29 studies, N = 2,637) indicated that the interaction was robust (d = .779), with low arousal leading to better immediate memory than high arousal, whereas high arousal led to better delayed memory than low arousal. Incorporating additional studies, a subsequent meta-analysis (48 studies, N = 3,143) on the effect of arousal on memory, taking retention delay as a moderator, provided further support. At a 2-min. delay, low arousal led to better immediate memory than high arousal (d = -.459). This difference decreased at a 20-min. delay (d = .106), when directions of high and low arousal effects on memory appeared to reverse. At longer delays than 20 min., high arousal led to better delayed memory than low arousal (ds = .753, .219, and .472, for delays of 45-min., 1-day, and more than 1-day, respectively).