Children's false memories: easier to elicit for a negative than for a neutral event

The present study examined the role of valence in the development of children's implanted false memories. Seventy-six 7-year-old children listened to two true and one false narrative. The false narrative was either neutral ("moving to another classroom") or emotional negative ("being accused by the teacher for copying off your neighbor"). In addition, half of the children were presented with their class photograph while listening to the narratives. During two interviews, children recalled as many details as possible from the true and false events. Results showed that the negative event elicited more false memories than the neutral event. The presentation of a true photograph did not promote the development of false memories.     

Phenomenal characteristics of autobiographical memories for positive,negative, and neutral events

We investigated memory qualities for positive, negative, and neutral autobiographical events. Participants recalled two personal experiences of each type and then rated their memories on several characteristics (e.g. sensorial and contextual details). They also reported whether they ‘see’ the events in their memories from their own perspective (‘field’ memories) or whether they ‘see’ the self engaged in the event as an observer would (‘observer’ memories). Positive memories contained more sensorial (visual, smell, taste) and contextual (location, time) details than both negative and neutral events, whereas negative and neutral memories did not differ on most dimensions. Positive and negative events were more often recollected with a field perspective than neutral events. Finally, participants were classified in four groups according to the repressive coping style framework. Emotional memories of repressors were not less detailed than those of the other groups. Copyright © 2002 John Wiley & Sons, Ltd.     

The cost in remembering of ruminating on negative memories

This study investigated retrieval mechanisms that may be involved in memory for distressing stimuli. Forty-one nonclinical participants watched a video clip depicting the immediate aftermath of a serious car accident. Following this, half of the participants were instructed to focus attention on the victims of the accident and to consider the negative sequelae of their injuries. The remaining participants were not given any instructions. Following the Victim Focus/Control period, all participants completed a cued-recall task assessing their memory of the video clip. Overall, victim-related details were better recalled than nonvictim related details. It is important to note that participants in the Victim Focus condition retrieved fewer peripheral details than participants in the Control condition. These results suggest that people focusing attention on distressing aspects of an event can experience a cost in remembering other aspects of the event. These findings may be interpreted in terms of enhanced recollection of central events or retrieval-induced forgetting mechanisms to explain patterns of diminished memory for aspects of distressing events.     

False memories of emotional and neutral words

This study used the Deese-Roediger-McDermott paradigm to investigate the direction and the extent to which emotional valence in semantic word lists influences the formation of false memories (FM). The experimental paradigm consisted of 1) a study phase (learning of neutral and negative lists of words semantically associated to a non-presented critical lure (CL), 2) a free recall phase, and 3) a recognition phase. Participants had to indicate whether the displayed item was "new" (new item or non-studied CL) or "old" (studied list item). CL associated with negative word lists elicited significantly more FM than CL associated with neutral word lists. This finding is in contrast to previous work showing that emotional words elicit fewer FM than neutral words. The results of our study also suggest that valence is capable of influencing emotional memory in terms of encoding and retrieval processes.     

The neural correlates of visual self-recognition

This paper presents a review of studies that were aimed at determining which brain regions are recruited during visual self-recognition, with a particular focus on self-face recognition. A complex bilateral network, involving frontal, parietal and occipital areas, appears to be associated with self-face recognition, with a particularly high implication of the right hemisphere. Results indicate that it remains difficult to determine which specific cognitive operation is reflected by each recruited brain area, in part due to the variability of used control stimuli and experimental tasks. A synthesis of the interpretations provided by previous studies is presented. The relevance of using self-recognition as an indicator of self-awareness is discussed. We argue that a major aim of future research in the field should be to identify more clearly the cognitive operations induced by the perception of the self-face, and search for dissociations between neural correlates and cognitive components.     

The neural correlates of alcohol-related aggression

Alcohol intoxication is implicated in approximately half of all violent crimes. Over the past several decades, numerous theories have been proposed to account for the influence of alcohol on aggression. Nearly all of these theories imply that altered functioning in the prefrontal cortex is a proximal cause. In the present functional magnetic resonance imaging (fMRI) experiment, 50 healthy young men consumed either a low dose of alcohol or a placebo and completed an aggression paradigm against provocative and nonprovocative opponents. Provocation did not affect neural responses. However, relative to sober participants, during acts of aggression, intoxicated participants showed decreased activity in the prefrontal cortex, caudate, and ventral striatum, but heightened activation in the hippocampus. Among intoxicated participants, but not among sober participants, aggressive behavior was positively correlated with activation in the medial and dorsolateral prefrontal cortex. These results support theories that posit a role for prefrontal cortical dysfunction as an important factor in intoxicated aggression.     

The neural correlates of everyday recognition memory

We used a novel automatic camera, SenseCam, to create a recognition memory test for real-life events. Adapting a 'Remember/Know' paradigm, we asked healthy undergraduates, who wore SenseCam for 2 days, in their everyday environments, to classify images as strongly or weakly remembered, strongly or weakly familiar or novel, while brain activation was recorded with functional MRI. Overlapping, widely distributed sets of brain regions were activated by recollected and familiar stimuli. Within the medial temporal lobes, 'Remember' responses specifically elicited greater activity in the right anterior and posterior parahippocampal gyrus than 'Know' responses. 'New' responses activated anterior parahippocampal regions. A parametric analysis, across correctly recognised items, revealed increasing activation in the right hippocampus and posterior parahippocampal gyrus (pPHG). This may reflect modulation of these regions by the degree of recollection or, alternatively, by increasing memory strength. Strong recollection elicited greater activity in the left posterior hippocampus/pPHG than weak recollection indicating that this region is specifically modulated by the degree of recollection.     

The effect of cognitive load and hyperarousal on negative intrusive memories

Clinical theories of post-traumatic stress suggest that encoding processes at the time of a trauma are critical in determining whether intrusive memories will develop. Potential mechanisms that might influence the development of intrusive memories were studied, as was objective memory performance. In an analogue design, 65 participants were randomised to three conditions (cognitive load, hyperventilation, and control), and then watched a film of traumatic content. Intrusive memories were recorded during the experimental phase and at 1-week follow-up. Support was found for the prediction that verbal cognitive load and hyperventilation would facilitate intrusion development immediately following exposure to the trauma film; however, this was not maintained at follow-up. Consistent with cognitive models of post-traumatic stress, thought suppression and the distress associated with intrusive experiences mediated the relationship between distress caused by the film and intrusions at 1-week follow-up. Objective memory testing indicated that the three experimental groups showed similar recall and recognition performance for the content of the film; however, relative to the control group, individuals in the cognitive load condition were significantly less able to place film scenes in the correct order.     

The effect of limited attention and delay on negative arousing false memories

ABSTRACT

Previous research has shown that, in comparison to neutral stimuli, false memories for high arousing negative stimuli are greater after very fast presentation and limited attention at study. However, full compared to limited attention conditions still produce comparably more false memories for all stimuli types. Research has also shown that emotional stimuli benefit from a period of consolidation. What effect would such consolidation have on false memory formation even when attention is limited at study? The aim of the present study was to investigate the effect of fast presentation on false memory production for negatively-arousing and neutral items over time using the DRM paradigm. Sixty-eight participants studied Negative and neutral DRM lists with fast or slow presentation conditions. Half completed a recognition test immediately and half completed a recognition test after one-week. Results revealed that, for fast presentation, negative critical lures increased after one week and were comparable to negative critical lures in the slow presentation encoding conditions. Neutral critical lures in the fast presentation condition did not change and remained lower compared to the slow presentation condition. These findings are the first demonstration that arousing negative false memories can increase over time when attention at encoding is limited.     

Stress administered prior to encoding impairs neutral but enhances emotional long-term episodic memories

Stressful events frequently comprise both neutral and emotionally arousing information, yet the impact of stress on emotional and neutral events is still not fully understood. The hippocampus and frontal cortex have dense concentrations of receptors for stress hormones, such as cortisol, which at high levels can impair performance on hippocampally dependent memory tasks. Yet, the same stress hormones can facilitate memory for emotional information, which involves interactions between the hippocampus and amygdala. Here, we induced psychosocial stress prior to encoding and examined its long-term effects on memory for emotional and neutral episodes. The stress manipulation disrupted long-term memory for a neutral episode, but facilitated long-term memory for an equivalent emotional episode compared with a control condition. The stress manipulation also increased salivary cortisol, catecholamines as indicated by the presence of alpha-amylase, heart rate, and subjectively reported stress. Stressed subjects reported more false memories than nonstressed control subjects, and these false memories correlated positively with cortisol levels, providing evidence for a relationship between stress and false memory formation. Our results demonstrate that stress, when administered prior to encoding, produces different patterns of long-term remembering for neutral and emotional episodes. These differences likely emerge from differential actions of stress hormones on memory-relevant regions of the brain.     

The awareness of thirst: proposed neural correlates

The neural and endocrine bases of the generation of thirst are reviewed. Based on this review, a hierarchical system of neural structures that regulate water conservation and acquisition is proposed. The system includes primary sensory-receptive areas; secondary sensory structures (circumventricular organs), which detect levels of hormones, including angiotensin II and vasopressin, which are involved in generating thirst; preoptic and hypothalamic structures; and an area within the ventrolateral quadrant of the periaqueductal gray matter. Hodological and other data are used to determine the hierarchical organization of the system. Based on studies of the effects of lesions to various structures within the hierarchy of the system, it is proposed that the awareness of thirst in rodents is either entirely or predominantly due to neuronal activities in a subsection of the ventrolateral periaqueductal gray matter. It is also hypothesized that the awareness of thirst in primates is due to neuronal activities in both the ventrolateral periaqueductal gray and in a region within the medial prefrontal and anterior cingulate cortex.     

Retrieving positive memories to regulate negative mood: consequences for mood-congruent memory

Several researchers have suggested that mood-incongruency effects are due to a mood-regulatory process in which people retrieve positive memories to repair negative moods. The present studies tested this idea by manipulating mood-repair strategies and examining their impact on positive and negative memory retrieval. Mood-congruent retrieval occurred when participants stayed focused on events associated with their negative mood; mood-incongruent retrieval occurred when participants engaged in positive reappraisal (when they reinterpreted events as having positive outcomes). The effects of these strategies on memory retrieval also interacted with personality traits related to negative mood regulation. Individuals high in such traits showed stronger mood-incongruent memory than did individuals low in negative mood-regulation traits. Discussion focuses on integrating mood-regulatory variables and personality variables into existing mood-congruency theories (e.g., associative network models).     

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.     

Prime time news: The influence of primed positive and negative emotion on susceptibility to false memories

We examined the relation between emotion and susceptibility to misinformation using a novel paradigm, the ambiguous stimuli affective priming (ASAP) paradigm. Participants (N = 88) viewed ambiguous neutral images primed either at encoding or retrieval to be interpreted as either highly positive or negative (or neutral/not primed). After viewing the images, they either were asked misleading or non-leading questions. Following a delay, memory accuracy for the original images was assessed. Results indicated that any emotional priming at encoding led to a higher susceptibility to misinformation relative to priming at recall. In particular, inducing a negative interpretation of the image at encoding led to an increased susceptibility of false memories for major misinformation (an entire object not actually present in the scene). In contrast, this pattern was reversed when priming was used at recall; a negative reinterpretation of the image decreased memory distortion relative to unprimed images. These findings suggest that, with precise experimental control, the experience of emotion at event encoding, in particular, is implicated in false memory susceptibility.     

Forgetting to forget: On the duration of voluntary suppression of neutral and emotional memories

Can we control the content of our memory and forget what we do not want to think about by an act of will? If so, is forgetting temporary or permanent, and is it independent of the nature of what we wish to forget? Using Anderson and Green’s (2001) “think/no-think” paradigm with neutral and emotional nouns, we found in agreement with other studies that memory for neutral words was reduced instantly upon repeated attempts at suppression. However, the effect was temporary and vanished after a period of one week, which strongly suggests that intended memory suppression interferes with immediate retrieval but does not lead to long-term forgetting. Furthermore, the amount of training that clearly reduced immediate recall of neutral items did not at all reduce recall of emotional items. This finding is in accordance with the notion that emotional items have a higher degree of salience and tend to attract more attention than neutral items.     

Psychological correlates of negative self-assessed health

The recent growth in the area now subsumed under the title health psychology can be seen to reflect real changes in the societal pre-occupation with health promotion. Established models within health psychology have tended to focus on the interface between the individual and the health care system. Moreover, as a consequence of employing the tripartite model of health, illness and sick-role behaviour as separate entities, research has tended to construct barriers between these behaviours. In is necessary to develop psychological models within health psychology rather than use the education model of the medical orthodoxy. This study explored the distinguishing features of a sub-group of women within the sample who were identified as having relatively negative self-assessed health. Data was obtained on their experience of health and illness, their involvement in health-related behaviours (HRB) and their health beliefs. It was shown that this group was more likely to be involved in damaging HRB, but involvement in positive HRB did not differ from the main sample. They tended to anticipate an improvement over time from their present health status which they felt had been influenced by their own behaviour and by their experience of motherhood.     

Self-ratings of positive and negative affect and retrieval of positive and negative affect memories

Abstract

Based on analysis of self-ratings of mood, positive affect (PA) and negative affect (NA) have been proposed as basic, orthogonal mood dimensions (Watson & Tellegen, 1985). The present study asked subjects (N = 61) to not only provide self-ratings of PA and NA terms but also to retrieve personal memories associated with those terms. Self-rated PA was associated with latency to retrieve PA- but not NA-related memories; self-rated NA was associated with latency to retrieve NA- but not PA-related memories. Self-ratings of PA and NA were not significantly correlated, nor were retrieval latencies for PA and NA memories. Individual item correlations also revealed a strong direct relationship between self-ratings and retrieval latency. The dissociations involving a non-self report measure strengthen the distinction between PA and NA, and the individual item correlations are interpreted as showing that self-ratings of affect are based upon the ease of retrieval of personal memories.