Arousal-But Not Valence-Reduces False Memories at Retrieval

Contradictory findings in the study of emotional false memory: a review on the inadvisability of controlling valence and arousal

Emotional false memories are the erroneous recollection of events accompanied by an emotional experience. In high-risk domains like psychotherapy and the legal system, emotional false memories are of particular importance. Despite the systematic research conducted on emotional false memories in recent years, findings remain contradictory. Some studies have suggested that negative emotion reduces false memories, while others have suggested that negative emotion increases false memories. Research has mainly employed words and pictures as experimental stimuli, and studies using both types of memory stimuli are reviewed here. From this examination, it emerged that the main reasons for contradictory findings are as follows: (1) different materials have varying effects on inducing false memories, with pictures demonstrating a memory advantage compared to words; (2) recall and recognition tests have been used interchangeably, leading to different false-memory effects depending on the memory test employed; and (3) different studies have adopted different levels of control over valence and arousal when manipulating emotional variables. Future studies should distinguish between the use of different memory materials, examine specific differences in recall and recognition tests, and measure the impact of specific emotions on false memory beyond the dimensions of valence and arousal.

When is memory more reliable? Scientific findings, theories, and myths

The question of whether human memory is reliable generated extensive research. Memory is open to reconstruction and false retrieval of unpresented information or unexperienced events. These can create problems in judgments and decisions that rely on memory accuracy. In the case of eyewitness testimony, these problems can result in injustice. Then again, memory is also reliable enough. Information acquisition, processing, and retrieval capacity of our memory made it possible to survive the course of evolution. Our memory also makes it possible to continue our daily lives, most of the time without major problems. In the present review, we suggest that the right question to ask may not be whether memory is reliable, but rather to ask when and under what circumstances memory is more reliable. The review's educational aim is to identify the conditions under which memory is more versus less reliable, and its theoretical aim is to discuss memory reliability. We reviewed the literature on situational, emotional, social, and individual difference variables that affect memory reliability, identified the conditions under which memory is more versus less reliable, summarized these outcomes as easy-to-reach items, and discussed them in the light of major theories. Our discussion also touched upon the differentiation of societal myths about the reliability of memory from scientific findings, since believing in memory myths can also affect the reliability of memory. Awareness of the specific circumstances under which memory is more reliable can lead to the consideration of how much memory can be trusted under those specific circumstances.

Emotional dissociations in temporal associations: opposing effects of arousal on memory for details surrounding unpleasant events

Research targeting emotion's impact on relational episodic memory has largely focused on spatial aspects, but less is known about emotion's impact on memory for an event's temporal associations. The present research investigated this topic. Participants viewed a series of interspersed negative and neutral images with instructions to create stories linking successive images. Later, participants performed a surprise memory test, which measured temporal associations between pairs of consecutive pictures where one picture was negative and one was neutral. Analyses focused on how the order of negative and neutral images during encoding influenced retrieval accuracy. Converging results from a discovery study (N = 72) and pre-registered replication study (N = 150) revealed a "forward-favouring" effect of emotion in temporal memory encoding: Participants encoded associations between negative stimuli and subsequent neutral stimuli more strongly than associations between negative stimuli and preceding neutral stimuli. This finding may reflect a novel trade-off regarding emotion's effects on memory and is relevant for understanding affective disorders, as key clinical symptoms can be conceptualised as maladaptive memory retrieval of temporal details.

Associations between the misinformation effect, trauma exposure and symptoms of posttraumatic stress disorder and depression

This research aimed to conduct an initial investigation into the relationships between the "misinformation effect" and trauma exposure, posttraumatic stress disorder (PTSD) and depression. Study 1 was a pilot study developing an online misinformation paradigm that could assess the influence of emotion and arousal on memory distortions. Participants (n = 162, M_age = 39.90; SD = 10.90) were recruited through TurkPrime. In Study 2 community members (n = 116, M_age = 28.96; SD = 10.33) completed this misinformation paradigm and measures of trauma exposure, PTSD, and depression. Study 1 found memory for central details was better for high-arousal than low-arousal and neutral-arousal images. Peripheral memory appeared worse for negative and neutral images than positive images. Study 2 found that, when controlling for age and gender, PTSD symptoms significantly predicted proportion of correct responses on control items. However, there was no evidence to indicate that trauma exposure, PTSD symptoms nor depression symptoms, were associated with proportion of correct responses on misled items. Valence and arousal did not influence these associations. These findings have important implications in clinical and legal contexts where individuals with a history of trauma, or who are experiencing symptoms of PTSD or depression, are often required to recall emotionally-laden events. There is a surprising dearth of research into the misinformation effect in clinical populations and further research is required.

Psychopathic personality traits are linked to reduced false memories for negative events

Individuals scoring high on psychopathic personality traits process emotional material to a different extent than individuals with few psychopathic traits. Evidence exists that these individuals have impaired emotional memory. The question arises whether this emotional memory impairment has ramifications for the production of emotional false memories. In the present study, we investigated the production of false and true memories for emotional events in a community sample (N = 120) of individuals varying in psychopathic traits (evaluated with the Psychopathic Personality Inventory-Revised [PPI-R] questionnaire). The fearless dominance (FD) component of psychopathy interacted with the emotional impact of to-be-remembered events in the production of false memories, showing fewer negative false memories with increasing levels of FD. At the subjective level, negative false memories were not perceived as vivid memory experiences in high FD individuals. Concerning true memories, higher scores in cold-heartedness were related to fewer true memories for neutral and negative (but not positive) events. These results show that individuals with high psychopathy traits - in particular, FD - do not have a general emotional memory impairment but they process negative material in a different way than individuals with low psychopathic traits and thus are less susceptible to producing false memories for negative events.

A systematic review of the relationship between emotion and susceptibility to misinformation

Inaccurate memory reports can have serious consequences within forensic and clinical settings, where emotion and misinformation are two common sources of memory distortion. Many studies have investigated how these factors are related; does emotion protect memory or leave it more vulnerable to the distorting effects of misinformation? The findings remain diffused. Thus, the present review aimed to clarify the relationship between emotion and susceptibility to misinformation. 39 eligible studies were reviewed. Results varied according to the type and dimension of emotion measured. Level of arousal may be unrelated to susceptibility to misinformation when retrieval occurs without delay; studies including delayed retrieval were limited. Stimuli valence may be associated with increased susceptibility to peripheral misinformation but unrelated to other misinformation. The following results were reported by limited studies: short-term distress and moderate levels of stress may decrease susceptibility, while anger and greater cortisol response to stress may increase susceptibility to misinformation. Source memory may also be unaffected by emotion. The results have important potential implications for forensic and clinical practice, for example by highlighting the value of enquiring witnesses' source memory. Methodological recommendations for future studies are made.

Working Memory Beats Age: Evidence of the Influence of Working Memory on the Production of Children's Emotional False Memories

Emotional valence and working memory ability (WM) affect false memories’ production in adults. Whereas a number of studies have investigated the role of emotional valence in children’s tendency to produce spontaneous false memories, individual differences in WM have not been previously included. In the current article, we were interested in investigating whether emotion and WM would interact in influencing the propensity to incur inferential false memories for scripted events. Ninety-eight typically developing children (first-, third-, and eighth- graders) were administered the Emotional false memory paradigm – allowing to study false memories for negative, positive, and neutral events – and a WM task. Results showed that regardless of age, valence influenced false memories’ production, such that positive events protected against incurring distortions. Furthermore, WM interacted with valence, such that children with higher WM abilities produced fewer false memories for negative events. Concerning confidence judgments, only the youngest group of children claimed to be overconfident when committing false memories for negative and neutral events. Results are discussed in terms of the role of individual differences in higher cognitive abilities interacting with the emotional content of to-be-remembered events.

Bridging the Translational Divide in Pain Research: Biological, Psychological and Social Considerations

A gap exists between translating basic science research into effective pain therapies in humans. While preclinical pain research has primarily used animal models to understand biological processes, a lesser focus has been toward using animal models to fully consider other components of the pain experience, such as psychological and social influences. Herein, we provide an overview of translational studies within pain research by breaking them down into purely biological, psychological and social influences using a framework derived from the biopsychosocial model. We draw from a wide landscape of studies to illustrate that the pain experience is highly intricate, and every attempt must be made to address its multiple components and interactors to aid in fully understanding its complexity. We highlight our work where we have developed animal models to assess the cognitive and social effects on pain modulation while conducting parallel experiments in people that provide proof-of-importance for human pain modulation. In some instances, human pain research has sparked the development of novel animal models, with these animal models used to better understand the complexity of phenomena considered to be uniquely human such as placebo responses and empathy.

False memory for pictorial scripted material: the role of distinctiveness and negative emotion

Emotional content has complex effects on false memory. Under certain circumstances, emotional material may reduce the likelihood of false memory, a phenomenon that some consider related to it being more distinctive than neutral stimuli. In the present study we tested inferential false memory related to emotionally neutral or negative, and distinctive (but not emotionally charged) scripted material. Remember/familiar judgements were required for recognised stimuli. Data were analysed using mixed-effects multinomial regressions and a Bayesian inferential approach. Results obtained with 82 adult participants showed that, compared with neutral material: distinctive material reduced their false memory associated with "remember" and "familiar" judgements, virtually to the same extent; negatively-charged material reduced false memory associated with "remember" judgements but it had no effect on false memory associated with "familiar" judgements. In short, negatively-charged and distinctive material seems to affect false memory in different ways: the latter affects both recollection and familiarity, the former only recollection.

Induced affective states do not modulate effort avoidance

Recent research reveals that when faced with alternative lines of action, humans tend to choose the less cognitively demanding one, suggesting that cognitive control is intrinsically registered as costly. This idea is further supported by studies showing that the exertion of cognitive control evokes negative affective states. Despite extensive evidence for mood-induced modulations on control abilities, the impact of affective states on the avoidance of cognitive demand is still unknown. Across two well-powered experiments, we tested the hypothesis that negative affective states would increase the avoidance of cognitively demanding tasks. Contrary to our expectations, induced affective states did not modulate the avoidance of demand, despite having an effect on task performance and subjective experience. Altogether, our results indicate that there are limits to the effect of affective signals on cognitive control and that such interaction might depend on specific affective and control settings.

Emotional Recognition in Schizophrenia: An Analysis of Response Components in Middle-Aged Adults

Ageing seems to present a bias towards positive stimuli that might be reflected in response times. However, this process is more complex for middle-aged adults, and even more in schizophrenia. In order to examine this issue, an experimental study was carried out in which 48 participants were divided into two groups: an experimental group of 24 participants diagnosed with schizophrenia and a control group of 24 subjects with no disorders. The main objective of the study was to evaluate response time components according to the emotional valence of the stimulus, to test recognition and discrimination in both groups. A battery of 120 images from the International Affective Picture System (IAPS), representing positive, negative and neutral emotional valences, was employed. Response times were evaluated in terms of analysis of variance, as well as its inherent response times components. The results showed slower responses in the group with schizophrenia than in the control one. Moreover, a poorer performance was depicted in the latency components this group. Finally, a differential deficit pattern for emotion between groups was not found.

Inferential false memories for emotional events in older adults

Emotional events have been shown to protect individuals against false memory when remembering scripted material. Whether the same is true also for older adults, however, is unclear, and it has been investigated in the present study. Seventy-six older adults (age range 65-89 years) were presented with a series of photographs depicting scripted events. Each event included the consequence of an action whose corresponding cause was not presented; the consequence was either neutral, negative, or positive. False recognitions of unseen causes of the consequences (i.e., 'causal errors') were calculated. A Bayesian inferential approach was adopted in order to include evidence from previous studies and to use it as a benchmark for newly collected information. Older adults showed enhanced false memories and lower accuracy than previously reported in studies on young adults. Compared to neutral ones, both negative and positive events were associated with fewer false memories in older adults. The emotional false memory 'profile' of older adults was very similar, in terms of the effect size, to the one previously found in young adults, although the overall chances of older adults incurring errors were higher. Results are discussed considering both cognitive and socioemotional hypotheses on emotional memory in late adulthood.

Hippocampal morphology mediates biased memories of chronic pain

Experiences and memories are often mismatched. While multiple studies have investigated psychological underpinnings of recall error with respect to emotional events, the neurobiological mechanisms underlying the divergence between experiences and memories remain relatively unexplored in the domain of chronic pain. Here we examined the discrepancy between experienced chronic low back pain (CBP) intensity (twice daily ratings) and remembered pain intensity (n = 48 subjects) relative to psychometric properties, hippocampus morphology, memory capabilities, and personality traits related to reward. 77% of CBP patients exaggerated remembered pain, which depended on their strongest experienced pain and their most recent mood rating. This bias persisted over nearly 1 year and was related to reward memory bias and loss aversion. Shape displacement of a specific region in the left posterior hippocampus mediated personality effects on pain memory bias, predicted pain memory bias in a validation CBP group (n = 21), and accounted for 55% of the variance of pain memory bias. In two independent groups (n = 20/group), morphology of this region was stable over time and unperturbed by the development of chronic pain. These results imply that a localized hippocampal circuit, and personality traits associated with reward processing, largely determine exaggeration of daily pain experiences in chronic pain patients.

What happened first? Working memory and negative emotion tell you better: evidence from a temporal binding task

Emotionally arousing events may disrupt the ability to bind together different features of items to their context; this holds true both for spatial binding (i.e. remembering the locations of previously presented items) and temporal binding (i.e. remembering the order in which different items were previously presented). Nonetheless, memory for emotional events may be enhanced in certain situations. A key factor that might explain the memory-emotion relation is represented by individual differences in cognition. The present study investigated temporal binding for neutral and negative events in a group of 50 undergraduate students, focusing on the role of individual differences in working memory (measured through forward and backward digit span tasks). Temporal binding was assessed with sorting accuracy of various pictorial scripted events, 24 h after encoding. Results showed that higher backward digit span predicted higher binding accuracy; importantly, this was qualified by the interaction with valence, such that higher backward digit span predicted better performance for negative, but not neutral, events. It is concluded that working memory facilitates binding of emotional events to their temporal context during encoding, creating a strong representation, and favouring later retrieval of such bound representations.