Cognitive avoidance of intrusive memories: recall vantage perspective and associations with depression

Although recent research demonstrates that intrusive memories represent an overlapping cognitive feature of depression and post-traumatic stress disorder (PTSD), there is still a general paucity of research investigating the prevalence and maintenance of intrusive memories in depression. The current study investigated the association between a range of cognitive avoidant mechanisms that characterize PTSD samples (i.e., suppression, rumination, emotional detachment, and an observer vantage perspective) and intrusive memories of negative autobiographical events in relation to dysphoria. Hypotheses were based on the proposition that employment of these cognitive mechanisms would hinder the emotional processing of the negative event, thus contributing to the maintenance of intrusions. Results supported an association between negative intrusive memories, dysphoria, and avoidant mechanisms. Significant differences were also found between field and observer memories and measures of emotional detachment and rumination. Implications relating to intrusive memory maintenance and treatment approaches are discussed.     

Trauma‐related rumination mediates the effect of naturally occurring depressive symptoms but not momentary low mood on trauma intrusions

Comorbid depression is known to contribute to the maintenance of posttraumatic stress disorder (PTSD) including distressing intrusive trauma memories. It is theorised that depression is a risk factor for persistent PTSD through preventing optimal habituation of distress provoked by trauma memories and reminders, but the underlying cognitive mechanisms responsible are uncertain. The present study investigated trauma‐related rumination as a possible mediator for the effect of depression on trauma intrusions. Participants received a low mood induction or control procedure. Following viewing an analogue trauma film, frequency of film‐related intrusions and associated distress levels were measured and at 1‐week follow‐up. Between the two occasions, participants rated their levels of rumination about the film. Existing depression symptoms but not induced momentary sad mood predicted frequency of film intrusions and associated distress at 1‐week follow‐up. Some evidence was found that ruminative trauma processing mediated the relationship between baseline depressive symptoms and later intrusion frequency and associated distress. Future research is warranted to better understand the role of rumination in the depression–intrusion relationship, which may shed light on the clinical applicability of rumination‐targeted intervention for PTSD and comorbid depression.     

The Effects of Experimentally Induced Rumination Versus Distraction on Analogue Posttraumatic Stress Symptoms

Rumination has been suggested to be an important factor maintaining posttraumatic stress disorder (PTSD). Using an analogue design, this study aimed to experimentally test the hypothesis that trauma-related rumination maintains PTSD symptoms. Fifty-one participants were first asked to give a detailed narrative of a negative life event and were then randomly assigned to a rumination or distraction condition. In line with the hypotheses, rumination about the event resulted in the maintenance of negative mood and intrusive memories immediately after the manipulation whereas distraction resulted in symptom reduction. However, this effect was reversed during a subsequent symptom provocation task, in which distraction led to a greater increase in some of the symptoms than rumination. Results are in line with the idea that rumination is involved in the maintenance of PTSD but may suggest a complex relationship between rumination and posttraumatic stress symptoms.     

Intrusive re‐experiencing in post‐traumatic stress disorder: Phenomenology,theory, and therapy

The article describes features of trauma memories in post‐traumatic stress disorder (PTSD), including characteristics of unintentional re‐experiencing symptoms and intentional recall of trauma narratives. Re‐experiencing symptoms are usually sensory impressions and emotional responses from the trauma that appear to lack a time perspective and a context. The vast majority of intrusive memories can be interpreted as re‐experiencing of warning signals, i.e., stimuli that signalled the onset of the trauma or of moments when the meaning of the event changed for the worse. Triggers of re‐experiencing symptoms include stimuli that have perceptual similarity to cues accompanying the traumatic event. Intentional recall of the trauma in PTSD may be characterised by confusion about temporal order, and difficulty in accessing important details, both of which contribute to problematic appraisals. Recall tends to be disjointed. When patients with PTSD deliberately recall the worst moments of the trauma, they often do not access other relevant (usually subsequent) information that would correct impressions/predictions made at the time. A theoretical analysis of re‐experiencing symptoms and their triggers is offered, and implications for treatment are discussed. These include the need to actively incorporate updating information ( “I know now …”) into the worst moments of the trauma memory, and to train patients to discriminate between the stimuli that were present during the trauma ( “then”) and the innocuous triggers of re‐experiencing symptoms ( “now”).     

Overgeneral memory extends to pictorial retrieval cues and correlates with cognitive features in posttraumatic stress disorder

Individuals with posttraumatic stress disorder (PTSD) show overgeneral memory (OGM) when retrieving autobiographical memories to word cues. We investigated whether OGM extends to picture cues and whether it is related to PTSD symptoms and cognitions. Trauma survivors with (n = 29) and without (n = 26) PTSD completed the standard Autobiographical Memory Test (AMT) and a novel picture version. Compared to the no-PTSD group, the PTSD group showed OGM in both test versions. Pictures facilitated specific memory retrieval, but this effect was no longer significant when verbal intelligence or depressive symptoms were controlled. OGM correlated with PTSD symptoms and perceived self-change; with intrusive memories, their perceived "nowness," responses to intrusions (thought suppression, rumination, dissociation), and negative interpretations of symptoms.     

Overgeneral memory and suppression of trauma memories in post-traumatic stress disorder

The study investigated the relationship between the suppression of trauma memories and overgeneral memory in 42 assault survivors with and without PTSD. Overgeneral memory (OGM) was assessed with a standard autobiographical memory test (AMT). Participants completed two further AMTs under the instructions to either suppress or not suppress assault memories, in counterbalanced order. Participants with PTSD retrieved fewer and more general memories when following the suppression instruction than participants without PTSD, but not under the control instruction. OGM correlated with PTSD symptom severity, and measures of cognitive avoidance. The results are discussed with reference to current theories of overgeneral memory and its possible relationship with PTSD.     

Reliving,emotions, and fragmentation in the autobiographical memories of veterans diagnosed with PTSD

Fifty veterans diagnosed with posttraumatic stress disorder (PTSD) each recalled four autobiographical memories: one from the 2 years before service, one non‐combat memory from the time in service, one from combat, and one from service that had often come as an intrusive memory. For each memory, they provided 21 ratings about reliving, belief, sensory properties, reexperiencing emotions, visceral emotional responses, fragmentation, and narrative coherence. We used these ratings to examine three claims about traumatic memories: a separation of cognitive and visceral aspects of emotion, an increased sense of reliving, and increased fragmentation. There was evidence for a partial separation of cognitive judgments of reexperiencing an emotion and reports of visceral symptoms of the emotion, with visceral symptoms correlating more consistently with scores on PTSD tests. Reliving, but not fragmentation of the memories, increased with increases in the trauma relatedness of the event and with increases in scores on standardized tests of PTSD severity. Copyright © 2004 John Wiley & Sons, Ltd.     

The impact of depression and PTSD symptom severity on trauma memory

Posttraumatic stress disorder (PTSD) and depression frequently co-occur following a traumatic event. Differences in the processing of autobiographical memory have been observed in both disorders in the form of overgeneralised memories and negative intrusive memories. The current study examined how symptoms of PTSD and depression influence the phenomenological characteristics of trauma memories. Undergraduate students who had experienced a traumatic event (n?=?696) completed questionnaires online including measures of PTSD and depressive symptom severity. They rated their trauma memory on several phenomenological characteristics using the Memory Experiences Questionnaire [Sutin, A. R., &; Robins, R. W. (2007). Phenomenology of autobiographical memories: The memory experiences questionnaire. Memory.]. Moderated multiple regression was used to examine how PTSD and depressive symptom severity related to each phenomenological characteristic. Symptoms of PTSD and depression were related separately and uniquely to the phenomenological characteristics of the trauma memory. PTSD severity predicted trauma memories that were more negative, contained higher sensory detail, and were more vivid. In contrast, depressive symptom severity predicted trauma memories that were less accessible and less coherent. These findings suggest that depressive and PTSD symptomatology affect traumatic memory differently and support a distinction between these two disorders.     

Unwanted memories of assault: what intrusion characteristics are associated with PTSD?

Intrusive memories are common in the immediate aftermath of traumatic events, but neither their presence or frequency are good predictors of the persistence of posttraumatic stress disorder (PTSD). Two studies of assault survivors, a cross-sectional study (N=81) and a 6-month prospective longitudinal study (N=73), explored whether characteristics of the intrusive memories improve the prediction. Intrusion characteristics were assessed with an Intrusion Interview and an Intrusion Provocation Task. The distress caused by the intrusions, their "here and now" quality, and their lack of a context predicted PTSD severity. The presence of intrusive memories only explained 9% of the variance of PTSD severity at 6 months after assault. Among survivors with intrusions, intrusion frequency only explained 8% of the variance of PTSD symptom severity at 6 months. Nowness, distress and lack of context explained an additional 43% of the variance. These intrusion characteristics also predicted PTSD severity at 6 months over and above what could be predicted from PTSD diagnostic status at initial assessment. Further predictors of PTSD severity were rumination about the intrusive memories, and the ease and persistence with which intrusive memories could be triggered by photographs depicting assaults. The results have implications for the early identification of trauma survivors at risk of chronic PTSD.     

An investigation of the cognitive and experiential features of intrusive memories in depression

Intrusive autobiographical memories of negative past events are a clinical feature common to post-traumatic stress disorder (PTSD) and depression. Recent investigations provide increasing evidence that shared cognitive processes are linked to the maintenance of intrusive memories in both conditions. Still absent from the existing literature, however, is a systematic examination of the basic content and defining characteristics of intrusive memories in depression. This study sought to: (i) outline the content and features of intrusive memories in depression, and (ii) investigate whether intrusion characteristics linked to the persistence of intrusive memories in PTSD are also characteristic of intrusive memories in depression. A sample of undergraduate students (n=250) were interviewed and assessed for the presence of an intrusive memory in the past week, and completed a battery of measures that indexed cognitive and affective responses to the memory. Consistent with prediction, intrusive memories contained high levels of sensory experience and were marked by a sense of "nowness". In accord with studies with PTSD samples, sensory features accounted for unique variance in the prediction of depression severity, over and above that accounted for by intrusion frequency. This pattern of findings was replicated in a dysphoric (BDI-II>or=12) sub-sample of participants. Our results underscore the value of drawing on theoretical conceptualisations and empirical findings from the post-traumatic stress literature to extend our understanding of intrusive memories in depression.     

An investigation of the cognitive and experiential features of intrusive memories in depression

Intrusive autobiographical memories of negative past events are a clinical feature common to post-traumatic stress disorder (PTSD) and depression. Recent investigations provide increasing evidence that shared cognitive processes are linked to the maintenance of intrusive memories in both conditions. Still absent from the existing literature, however, is a systematic examination of the basic content and defining characteristics of intrusive memories in depression. This study sought to: (i) outline the content and features of intrusive memories in depression, and (ii) investigate whether intrusion characteristics linked to the persistence of intrusive memories in PTSD are also characteristic of intrusive memories in depression. A sample of undergraduate students (n=250) were interviewed and assessed for the presence of an intrusive memory in the past week, and completed a battery of measures that indexed cognitive and affective responses to the memory. Consistent with prediction, intrusive memories contained high levels of sensory experience and were marked by a sense of “nowness”. In accord with studies with PTSD samples, sensory features accounted for unique variance in the prediction of depression severity, over and above that accounted for by intrusion frequency. This pattern of findings was replicated in a dysphoric (BDI-II≥12) sub-sample of participants. Our results underscore the value of drawing on theoretical conceptualisations and empirical findings from the post-traumatic stress literature to extend our understanding of intrusive memories in depression.     

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 influence of data-driven processing on perceptions of memory quality and intrusive symptoms in children following traumatic events

Ehlers and Clark [(2000). A cognitive model of post-traumatic stress disorder. Behaviour Research and Therapy, 38, 319-345] cognitive model of post-traumatic stress disorder (PTSD) has been relatively untested with children. Seventy-five children (7-16 years) were interviewed within 4 weeks of an injury that led to hospital treatment to examine whether peri-traumatic processing strategies (data-driven processing and fear) were associated with perceptions of memory quality and intrusive memories. Perceptions of memory quality mediated the relationship between data-driven processing and intrusive reactions but not avoidance, arousal or depressive reactions. Finally, the relationship between peri-event fear and intrusion reactions was mediated by perceptions of memory quality even after data-driven processing was controlled. The implications of these findings are discussed in the context of a cognitive developmental model of PTSD in children.     

“Why” or “How”: The Effect of Concrete Versus Abstract Processing on Intrusive Memories Following Analogue Trauma

Emergency service workers, military personnel, and journalists working in conflict zones are regularly exposed to trauma as part of their jobs and suffer higher rates of posttraumatic stress compared with the general population. These individuals often know that they will be exposed to trauma and therefore have the opportunity to adopt potentially protective cognitive strategies. One cognitive strategy linked to better mood and recovery from upsetting events is concrete information processing. Conversely, abstract information processing is linked to the development of anxiety and depression. We trained 50 healthy participants to apply an abstract or concrete mode of processing to six traumatic film clips and to apply this mode of processing to a posttraining traumatic film. Intrusive memories of the films were recorded for 1 week and the Impact of Events Scale–Revised (IES-R; Weiss & Marmar, 1997) was completed at 1-week follow-up. As predicted, participants in the concrete condition reported significantly fewer intrusive memories in response to the films and had lower IES-R scores compared with those in the abstract condition. They also showed reduced emotional reactivity to the posttraining film. Self-reported proneness to intrusive memories in everyday life was significantly correlated with intrusive memories of the films, whereas trait rumination, trait dissociation, and sleep difficulties were not. Findings suggest that training individuals to adopt a concrete mode of information processing during analogue trauma may protect against the development of intrusive memories.     

Aussagen ??ber traumatische Erlebnisse

The manner in which traumatic events are processed and recalled remains highly controversial. A central issue in the debate is whether traumatic experiences affect memory differently than other events. In this paper, two lines of research are reviewed: (a) comparisons of characteristics of traumatic and other memories and (b) comparisons of characteristics of traumatic memories of trauma survivors with and without posttraumatic stress disorder (PTSD). While PTSD groups reported more intrusive memories than non-PTSD groups, there is no consistent evidence for memory fragmentation neither for traumatic events in general nor for PTSD patients. Implications for credibility assessments are discussed.     

Path analytic examination of a cognitive model of PTSD

Ehlers and Clark (2000) developed a cognitive model of posttraumatic stress disorder (PTSD) symptom maintenance which implicated the role of posttraumatic cognitions and aspects of the trauma memory in maintaining symptoms via an increased sense of current threat. The aim of the current study was to empirically test a variant of this model using path analysis. Participants in the current study were 514 undergraduates at a midwestern university who reported experiencing at least one traumatic event. Path analyses examined various models of the possible relationships between one’s posttraumatic cognitions and the centrality of the traumatic event to the sense of self (considered an aspect of memory integration) in predicting current level of PTSD symptoms. Results indicate that both event centrality and posttraumatic cognitions are unique and independent predictors of current symptom level. Overall, the results of this study support aspects of Ehlers and Clark’s cognitive model of PTSD; cognitive appraisals of the self and centrality of the event were highly related to levels of distress. However, the current study suggests that overly integrated trauma memories may lead to greater distress and not poorly integrated ones as suggested by Ehlers and Clark.     

The Influence of Thought Suppression and Cognitive Load on Intrusions and Memory Processes Following an Analogue Stressor

Ironic Process Theory and the role of thought suppression have been used in part to explain the phenomenon of intrusive memories in various disorders, including posttraumatic stress disorder. How thought suppression interacts with other cognitive processes believed to be instrumental in the development of traumatic intrusive memory is unclear. In an analogue study, thought suppression and cognitive processing was manipulated in 4 experimental groups after participants (n = 80) viewed a trauma film. The impact of suppression was examined in relation to self-reported intrusive experiences as well as via more objective methods (word stem and dot probe tasks) to assess potential preferential encoding of negative material. Cognitive load appeared to undermine thought suppression ability, with these participants experiencing more intrusions over the week relative to participants in all other conditions. This group also showed greater priming to negative film-related words, and both suppression groups demonstrated enhanced memory for film-related content on recognition testing. Thought suppression mediated the relationship between negative interpretations of initial intrusions and later intrusions experienced over the week. The findings are discussed in the context of ironic process theory and cognitive models of posttraumatic stress.     

Does post-event cognitive load undermine thought suppression and increase intrusive memories after exposure to an analogue stressor?

Ironic process theory has been used in part to explain the phenomenon of intrusive memories in various disorders including post-traumatic stress disorder. How thought suppression interacts with other cognitive processes believed to be instrumental in the development of traumatic intrusive memory was tested. In an analogue design 120 participants were randomised to five conditions, four of which also required participants to attempt to suppress intrusive memories after viewing a film of traumatic content. Participants in three conditions were also required to perform concurrent tasks that acted as a cognitive load during suppression. Intrusive memories were recorded during the experimental phase and at 1-week follow-up. Contrary to predictions, post-film processing did not undermine suppression success. There was some suggestion that post-film processing resulted in those participants experiencing intrusions of shorter duration than the no-suppression control group in two 5-minute intrusion monitoring intervals at the initial and follow-up phase of the experiment, but this was not reflected in a 1-week diary measure of intrusions. All experimental groups performed in a similar fashion in terms of memory testing of the film's content. The findings are discussed in the context of ironic process theory and cognitive models of post-traumatic stress.     

Cognitive predictors of posttraumatic stress disorder in children: results of a prospective longitudinal study

The present study explored whether cognitive factors specified in the Ehlers and Clark model (Behav. Res. Ther. 38 (2000) 319) of posttraumatic stress disorder (PTSD) predict chronic PTSD in children who had experienced a road traffic accident. Children were assessed at 2 weeks, 3 months, and 6 months after the accident. Data-driven processing during the accident, negative interpretation of intrusive memories, alienation from other people, anger, rumination, thought suppression and persistent dissociation at initial assessment predicted PTSD symptom severity at 3 and 6 months. On the basis of sex and stressor severity variables, 14% of the variance of PTSD symptoms at 6 months could be explained. The accuracy of the prediction increased to 49% or 53% when the cognitive variables measured at initial assessment or 3 months, respectively, were taken into account.     

Count out your intrusions: Effects of verbal encoding on intrusive memories

Peri-traumatic information processing is thought to affect the development of intrusive trauma memories. This study aimed to replicate and improve the study by Holmes, Brewin, and Hennessy (2004, Exp. 3) on the role of peri-traumatic verbal processing in analogue traumatic intrusion development. Participants viewed an aversive film under one of three conditions: counting backwards in 3s (“verbal interference”), verbalising emotions and thoughts (“verbal enhancement”), or without an extra task. A dual-process account of PTSD would predict that verbal interference would increase intrusion frequency compared to no task, whereas verbal enhancement would lead to a decrease. In contrast, mainstream memory theory predicts a decrease in intrusion frequency from any concurrent task that diverts attention away from the trauma film. The main finding was that the verbal interference task led to a decrease in intrusive memories of the film compared to the other two conditions. This finding does not support a dual-process account of PTSD, but is in line with general theories of memory and attention.