Role of prior negative cognitions on the development of intrusive thoughts

This analogue study examined how individuals' prior negative cognitions influenced intrusion frequency, intrusion‐related distress and thought suppression. Participants at high (HR) and low risk (LR) for interpreting their intrusive thoughts in a negative manner viewed a graphic trauma film and their subsequent intrusion development was assessed. HR participants experienced a greater frequency of intrusions and intrusion‐related distress compared to LR participants. Trait thought suppression moderated the relationship between risk for the negative interpretation of intrusions and intrusion frequency. The findings suggest that pre‐existing negative cognitions are influential in the development of intrusions following exposure to an analogue trauma.     

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.     

Depressed mood mediates the relationship between rumination and intrusions

Research suggests that rumination is a causal factor for intrusive memories. These are disturbing autobiographical memories that pop into one's mind involuntarily, spontaneously, and repetitively. A three‐wave longitudinal study was conducted to replicate this finding and to test whether one route via which rumination leads to (an increase in) intrusive memories is via depressed affect. Secondary school students (n = 72) filled out self‐report questionnaires measuring their level of rumination, depressive symptoms (DS), and intrusive memories. These were administered at three different points, with 3 weeks in between each measurement. Two types of rumination were measured, that is, depressive rumination and rumination in response to intrusions. Both bootstrapping analyses and cross‐lagged analyses yielded evidence for DS as a partial mediator of the relationship between rumination and intrusion frequency. Both depressive rumination and rumination about the content of intrusive memories seemed to be maladaptive: They may exacerbate negative emotions, which in turn trigger intrusive memories. Ruminative thinking also directly led to (an increase in) intrusive memories. These findings might suggest that people suffering from intrusive memories may benefit not only from therapies directly aimed at reducing intrusions but also from therapies aimed at reducing rumination and DS.     

Inducing and modulating intrusive emotional memories: a review of the trauma film paradigm

Highly affect-laden memory intrusions are a feature of several psychological disorders with intrusive images of trauma especially associated with post-traumatic stress disorder (PTSD). The trauma film paradigm provides a prospective experimental tool for investigating analogue peri-traumatic cognitive mechanisms underlying intrusion development. We review several historical papers and some more recent key studies that have used the trauma film paradigm. A heuristic diagram is presented, designed to simplify predictions about analogue peri-traumatic processing and intrusion development, which can also be related to the processing elements of recent cognitive models of PTSD. Results show intrusions can be induced in the laboratory and their frequency amplified/attenuated in line with predictions. Successful manipulations include competing task type (visuospatial vs. verbal) and use of a cognitive coping strategy. Studies show that spontaneous peri-traumatic dissociation also affects intrusion frequency although attempts to manipulate dissociation have failed. It is hoped that further use of this paradigm may lead to prophylactic training for at risk groups and an improved understanding of intrusions across psychopathologies.     

Reducing depressive intrusions via a computerized cognitive bias modification of appraisals task: Developing a cognitive vaccine

A feature of depression is the distressing experience of intrusive, negative memories. The maladaptive appraisals of such intrusions have been associated with symptom persistence. This study aimed to experimentally manipulate appraisals about depressive intrusions via a novel computerized cognitive bias modification (CBM) of appraisals paradigm, and to test the impact on depressive intrusion frequency for a standardized event (a depressive film). Forty-eight participants were randomly assigned to either a session of positive or negative CBM. Participants then watched a depressing film (including scenes of bereavement and bullying) and subsequently monitored the occurrence of depressive intrusions related to the film in a diary for one week. At one-week follow-up, participants completed additional measures of intrusions – the Impact of Event Scale (IES) and an intrusion provocation task. As predicted, compared to the negative condition, participants who underwent positive CBM showed a more positive appraisal bias. Further, one week later, positive CBM participants reported fewer intrusions of the film and had lower IES scores. Our findings demonstrate that it is possible to manipulate maladaptive appraisals about depressive intrusions via a computerized CBM task. Further, this effect transfers to reducing intrusive symptomatology related to a standardized event (a depressive film) over one week, suggesting novel clinical implications.     

Vantage perspective in analogue trauma memories: an experimental study

Vantage perspective during recall is thought to affect the emotionality and accessibility of distressing memories. This study aimed to test the effects of vantage perspective during recall on memory associated distress and intrusion development. An adapted version of the trauma film paradigm was used in an experimental design with three conditions. Participants were asked to listen to eyewitness reports of car accidents (e.g. Trauma Analogue Induction) and imagine the scenes vividly using mental imagery. Afterwards, they were asked to recall the most distressing scene from field perspective, observer perspective, or to recall a neutral image from observer perspective (control condition) (e.g. Trauma Analogue Recall). Recall from field perspective resulted in higher negative mood, state-anxiety, and a higher number of short-term intrusions compared to the observer perspective condition and control condition. Negative mood and state-anxiety were mediators in the relationship between vantage perspective and intrusions. In comparison to observer perspective, field perspective increased the amount of short-term intrusions as a result of higher levels of negative mood and state-anxiety after memory retrieval. Future research on the interaction between vantage perspective at recall and negative mood and anxiety effects is warranted.     

Recurrence of Posttraumatic Stress Disorder in Late Life: A Cognitive Aging Perspective

Clinical experience with older adults shows that many will experience PTSD symptoms in older adulthood because of trauma exposure early in life. Some of these patients struggled with PTSD in the distant past and remained symptomfree for decades only to have a recurrence of PTSD in late life. This paper outlines a cognitive aging explanation for the recurrence of PTSD. It is proposed that the age-related decreases in attention make the intrusion of trauma-related memories more likely. The increase in intrusive memories, combined with age-related decreases in working memory, explicit memory, and prospective memory, increases the subjective distress associated with the memories and results in a recurrence of PTSD.     

Trauma films, information processing, and intrusive memory development

Three experiments indexed the effect of various concurrent tasks, while watching a traumatic film, on intrusive memory development. Hypotheses were based on the dual-representation theory of posttraumatic stress disorder (C. R. Brewin, T. Dalgleish, & S. Joseph, 1996). Nonclinical participants viewed a trauma film under various encoding conditions and recorded any spontaneous intrusive memories of the film over the following week in a diary. Changes in state dissociation, heart rate, and mood were also measured. As predicted, performing a visuospatial pattern tapping task at encoding significantly reduced the frequency of later intrusions, whereas a verbal distraction task increased them. Intrusive memories were largely unrelated to recall and recognition measures. Increases in dissociation and decreases in heart rate during the film were also associated with later intrusions.     

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 role of rumination,attentional biases and stress in psychological distress

This experimental study examines the relationship between rumination and attentional bias. Additionally, the study aims to determine, within a diathesis‐stress framework, whether rumination or attentional bias (or both) can prospectively predict psychological distress. Eighty‐one participants completed selected measures of rumination and psychological distress at time one, in addition to experimental manipulations of rumination and mood, and measures of mood and attentional bias at time two. Seventy‐three participants (90% follow‐up) completed final measures of stress and psychological distress approximately 3 weeks later. In combination with negative mood, inducing rumination decreased positive attentional bias, whilst inducing distraction increased positive attentional bias. Rumination and stress interacted to predict change in psychological distress. Negative attentional bias showed a trend towards interacting with rumination and stress to predict dysphoria. The findings supported the proposed diathesis‐stress models. In addition, a causal relationship between rumination and positive attentional bias has been empirically established for the first time.     

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.     

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.     

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.     

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.     

Intrusive memories and rumination in patients with post-traumatic stress disorder: a phenomenological comparison

The aim of the study was to investigate the phenomenological differences between intrusive memories and rumination in PTSD. The study population consisted of 31 patients with PTSD referred for cognitive behavioural therapy to specialist services. A semi-structured interview was used to examine the characteristics of the most prominent intrusive memory and rumination. Intrusive memories were predominantly sensory experiences of short duration, whereas rumination was predominantly a thought process of longer duration. Shame was associated more with rumination than with intrusive memories. Anxiety, helplessness, numbness, and threat were greater at the time of the trauma than when experiencing the intrusive memory. In contrast, feelings like anger and sadness were greater when experiencing intrusive memories than at the time of the event. The distinction between intrusive memories and rumination is of clinical importance as intrusive memories usually decrease with imaginal reliving of the trauma, whereas rumination may require different therapeutic strategies, such as rumination-focused or mindfulness-based cognitive therapy.     

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.     

An analogue study of intrusions

According to cognitive theorists, intrusive trauma memories have their origin in how information during the event is processed. Two studies investigated functional cognitive strategies during medical crises that might protect against intrusions. In Study 1, interviews with health-care professionals were used to identify cognitive strategies judged to be effective in controlling emotions and dealing with medical crises. Study 2 systematically manipulated the use of those strategies in a trauma analogue film paradigm. Experimental participants reported fewer intrusions, and less fear and avoidance of film-related stimuli during the subsequent week than controls. The manipulation did not affect anxiety during the film or memory disorganization. Implications for cognitive theories of intrusion development are discussed.     

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.     

Distant Memories: A Prospective Study of Vantage Point of Trauma Memories

ABSTRACT— Adopting an observer perspective to recall trauma memories may function as a form of avoidance that maintains posttraumatic stress disorder (PTSD). We conducted a prospective study to analyze the relationship between memory vantage point and PTSD symptoms. Participants ( N = 947) identified the vantage point of their trauma memory and reported PTSD symptoms within 4 weeks of the trauma; 730 participants repeated this process 12 months later. Initially recalling the trauma from an observer vantage point was related to more severe PTSD symptoms at that time and 12 months later. Shifting from a field to an observer perspective a year after trauma was associated with greater PTSD severity at 12 months. These results suggest that remembering trauma from an observer vantage point is related to both immediate and ongoing PTSD symptoms.