Age differences in the neural correlates underlying control of emotional memory: An event-related potential study

Health appeal appraisal and memory in older adults: the effects of goal and valence framing

Relative to younger adults, older adults have a preference and memory advantage for appeals framed to focus on emotion goals (e.g., loving or caring) or positive outcomes (e.g., benefits of health behaviors). Here we examined whether combining goal (emotion vs. future) and valence framing (positive vs. negative) could optimize older adults' appraisal and memory for health appeals. Sixty younger (ages 18-29) and 60 older (ages 64-87) adults viewed, rated and recalled one of the four versions of a health pamphlet, each with a unique combination of goal and valence framing. The results showed a memory advantage for pamphlets focusing on emotion over future goals in both age groups. Older adults also showed a more favorable appraisal and a weak memory advantage for the positively- and emotion-framed pamphlet, relative to younger adults. Thus combining goal and valence framing could optimize the effectiveness of older adults' health appeal communication..

Extremely negative emotion interferes with cognition: Evidence from ERPs and time-varying brain network

In recent years, the relationship between emotion and cognition was a hot topic. However, it remains unclear which specific emotions can significantly interfere with cognition and how they do so. In this study, we designed a novel Affective Stroop experiment paradigm to investigate these issues. The extremely negative (EN), moderately negative (MN), moderately positive (MP), extremely positive (EP) and neutral pictures were displayed before Stroop tasks. The behavioral results revealed that EN emotion significantly interfered with cognitive performance compared to other types of emotions, with a significant increase in reaction time under the EN emotion condition (P < 0.05). Furthermore, the dynamic brain mechanisms were analyzed from both Event-Related Potential (ERP) and time-varying brain network perspectives. Results showed that EN emotion evoked larger N2, P3, and LPP amplitudes in the frontal, parietal, and occipital brain regions. In contrast, the Stroop task under EN condition led to smaller N2, P3, and LPP amplitudes compared to neutral condition. This indicates that EN emotion was prioritized and consumed more cognitive resources relative to neutral emotion. During the P3 and LPP stages, we observed enhanced bottom-up connections between the parietal and frontal regions while the processing of EN emotion. Additionally, there were stronger top-down cognitive control connections from the frontal to the occipital regions while processing the Stroop task under EN condition. These findings consistently suggest that EN emotion interferes with cognition by consuming more cognitive resources, and the brain needs to enhance cognitive control to support Stroop task execution.

Aging and distractor resistance in working memory: Does emotional valence matter?

Background

Emotional stimuli used as targets of working memory (WM) tasks can moderate age-related differences in WM performance, showing that aging is associated with reductions in negativity bias. This phenomenon is referred to as the positivity effect. However, there is little research on whether emotional distractors have a similar moderating effect. Moreover, the underlying neural mechanism of this effect has not been studied. In this study, we examined the behavioral and neurophysiological basis for age differences in resistance to emotional distractors within WM.

Methods

Older adults (n = 30, ages 60–74) and young adults (n = 35, ages 19–26) performed a 2-back task in which a digit was superimposed on a face with a happy, angry, or neutral expression as a distractor. Event-related potential (ERP) was simultaneously recorded to assess P2, N2, and later positive potential (LPP) amplitudes.

Results

Older adults were less accurate and slower than young adults on the WM task. Moreover, the results demonstrated a significant interaction between age and emotional valence on response accuracy, young adults' performance was worse when the distractor was neutral or positive than when it was negative, but there was no effect of the emotional valence of distractors on older adults’ WM performance. ERP analyses revealed greater P2 amplitude in older adults than young adults, regardless of the emotional valence of distractors. However, older adults and young adults did not differ on N2 or LPP amplitude, and negative distractors elicited greater N2 than positive distractors in both age groups.

Conclusions

The behavioral findings provided evidence of age-related reductions in negativity bias. Thus, the behavioral measures indicated a positivity effect in WM. However, the ERP results did not show this same interaction. These discrepant results raise questions about whether and to what extent older and young adults differ in controlling the effect of emotional distractors in WM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40359-022-00953-y.

The effect of memory cue duration on performance in the directed forgetting task in healthy aging

Although forgetting is usually considered a memory error, intentional forgetting can function as an adaptive mechanism. The current study examined the effect of increased processing time on directed forgetting in aging as a mechanism to compensate for age-related forgetting. Specifically, an item-method directed forgetting paradigm was used in conjunction with Remember/Know/New responding to examine the effect of cue duration (1, 3, 5 s) on directed forgetting and remembering in younger and older adults. Results indicated that increased processing time improved performance in both age groups. Critically, older adults exhibited a linear increase in directed remembering performance across all cue durations which was related to individual differences in cognitive reserve. Specifically, those older adults with the highest levels of cognitive functioning showed the greatest memory benefit in the longest cue duration condition. These findings indicate the importance of processing time in accounting for intentional memory performance in older adults.

Emotional Modulation of Episodic Memory in School-Age Children and Adults: An Event-Related Potential Study

The Emotional Enhancement of Memory (EEM) has been well-demonstrated in adults, but less is known about EEM in children. The present study tested the impact of emotional valence of pictures on episodic memory using behavioral and neurophysiological measures. Twenty-six 8- to 11-year-old children were tested and compared to 30 young adults. Both groups participated in pictures' intentional encoding tasks while event-related potentials (ERPs) were recorded, followed by immediate free recall tasks. Behavioral results revealed a general EEM in free recall performances in both groups, along with a negativity effect in children. ERP responses revealed a particular sensitivity to negative pictures in children with a late emotion effect at anterior clusters, as well as a greater successful encoding effect for emotional pictures compared to neutral ones. For adults, the emotion effect was more pronounced for positive pictures across all time windows from the centro-parietal to the frontal part, and localized in the left hemisphere. Positive pictures also elicited a greater successful encoding effect at anterior clusters in adults. By combining behavioral and neurophysiological measures to assess the EEM in children compared with adults, our study provides new knowledge concerning the interaction between emotional and memory processes during development.

Emotional memories are (usually) harder to forget: A meta-analysis of the item-method directed forgetting literature

The current meta-analysis explored whether emotional memories are less susceptible to item-method directed forgetting than neutral memories. Basic analyses revealed superior memory for remember (R) than forget (F) items in both the neutral, M = 19.6%, CI_95% [16.1, 23.1], and the emotional, M = 15.1%, CI_95% [12.4, 17.7], conditions. Directed forgetting in either valence condition was larger for (a) words than for other stimuli; (b) recall than recognition tests; (c) studies that used recall prior to recognition testing; (d) shorter lists; and (e) studies that included buffer items. Direct comparison of the magnitude of the directed forgetting effect across neutral and emotional conditions within studies revealed relatively diminished directed forgetting of emotional items compared to neutral items, with an average difference of 4.2%, CI_95% [2.0, 6.4]. However, the nature of this finding varied broadly across studies, meaning that whether - and to what degree - emotional memories are more resilient than neutral memories likely depends on the methodological features of the study in question. Moderator analyses revealed larger differences (a) in studies for which the emotional items were more arousing than the neutral items, and (b) when buffer items were included. Together, these findings suggest that emotional memories are often more resilient to intentional forgetting than neutral memories, although further research is necessary to characterize the circumstances under which these differences emerge.

Interactions of Emotion and Self-reference in Source Memory: An ERP Study

The way emotional information is encoded (e.g., deciding whether it is self-related or not) has been found to affect source memory. However, few studies have addressed how the emotional quality and self-referential properties of a stimulus interactively modulate brain responses during stimulus encoding and source memory recognition. In the current study, 22 participants completed five study-test cycles with negative, neutral, and positive words encoded in self-referential versus non-self-referential conditions, while event-related potentials of the electroencephalogram were recorded. An advantage of self-referential processing in source memory performance, reflected in increased recognition accuracy, was shown for neutral and positive words. At the electrophysiological level, self-referential words elicited increased amplitudes in later processing stages during encoding (700-1,200 ms) and were associated with the emergence of old/new effects in the 300-500 ms latency window linked to familiarity effects. In the 500-800 ms latency window, old/new effects emerged for all valence conditions except for negative words studied in the non-self-referential condition. Negative self-referential words also elicited a greater mobilization of post-retrieval monitoring processes, reflected in an enhanced mean amplitude in the 800-1,200 ms latency window. Together, the current findings suggest that valence and self-reference interactively modulate source memory. Specifically, negative self-related information is more likely to interfere with the recollection of source memory features.

ERP and behavioural measures of cognitive effort associated to forget negative and neutral words

The cognitive effort associated with remembering (R) vs forgetting (F) neutral and negative words was analyzed through a visual detection task integrated in an item-method directed forgetting task. Thirty-three younger adults participated in the experiment while their electrophysiological activity was registered in the study phase. The results shown: (1) negative words evoked more positive ERPs than neutral words on frontal regions, suggesting a preferential processing of negative words. (2) F-cues evoked more positive ERPs than R-cues did for neutral rather than negative words between 500 and 900 ms. This effect could reflect the difficulty in implementing inhibitory mechanisms on negative words. (3) At visual detection task, RTs for post-F probes were longer than for post-R probes. In 350-550 ms time window, ERPs were more positive for post-F probes than post-R probes in over right frontal regions and left medial parietal regions. Additionally, larger P2 were evoked by post-F negative probes than by post-R negative and post-F neutral ones. (4) In recognition test, participants recognized more negative TBF words than neutral ones. The ERP and behavioral results indicate that forgetting is more difficult than remembering, especially when words have a negative content, which implies a greater recruitment of parietal and frontal regions.

Influence of Reward Motivation on Directed Forgetting in Younger and Older Adults

An important feature of the memory system is the ability to forget, but aging is associated with declines in the ability to intentionally forget potentially due to declines in cognitive control. Despite cognitive deficits, older adults are sensitive to affective manipulations, such as reward motivation, and reward anticipation can improve older adults' memory performance. The goal of the current studies was to examine the effect of reward motivation on directed remembering and forgetting. Participants were healthy CloudResearch/Turk Prime workers aged 18-35 and 60-85. In Experiment 1, we conducted a typical item-method directed forgetting task using neutral words presented one at a time followed by a to-be-remembered (TBR) or to-be-forgotten (TBF) cue. A recognition memory test followed that included all words from the encoding task, as well as new words. We replicated prior findings of better memory for TBR compared to TBF items, but not typical age-related differences in recognition of TBF items. In Experiments 2-4, we repeated this paradigm except that in the second block of trials, each word was presented with a high ($0.75) or low ($0.01) reward cue indicating the value that could be earned if the item was successfully Remembered or Forgotten (depending on cue). During recognition, correct responses to target items (both TBR and TBF) resulted in the associated reward, but incorrect "old" responses resulted in a loss of $0.50. In three experiments, high rewards led to better memory for younger and older adults compared to low rewards, regardless of the directed cue to remember or forget the word. In Experiments 3 and 4, older adults showed typical deficits in directed forgetting, but this was across reward conditions. For older adults, there was no evidence that including reward motivation improved cognitive control abilities as high value reward anticipation did not improve directed forgetting. Instead, in line with hypotheses, high compared to low value reward anticipation leads to engagement of processes that result in better memory regardless of the TBR or TBF cue, and reward anticipation bolsters memory in a relatively automatic, rather than strategic, fashion that overrides one's ability to cognitively control encoding processes.