The influence of data-driven versus conceptually-driven processing on the development of PTSD-like symptoms

Relationship between anxiety sensitivity and post-traumatic stress symptoms in trauma-exposed adults: A meta-analysis

Given the high rate of trauma exposure among the general population, it is important to delineate the risk factors for post-traumatic stress disorder (PTSD). While historically implicated in panic disorder, anxiety sensitivity is increasingly found to play a role in PTSD. The present review investigated the size of the relationship between anxiety sensitivity and PTSD symptoms among trauma exposed adults. A systematic search on multiple electronic databases (PTSDpubs, CINAHL, MEDLINE and PsycINFO) generated a total of 1025 records, among which 52 (n = 15173) met study inclusion criteria and were included in our random effects meta-analysis. Our results indicated a medium effect size (r = .46, 95% CI =.41,.50) for the relationship between anxiety sensitivity and PTSD symptoms. There was significant between-study heterogeneity. Furthermore, sub-group analyses revealed that study design (cross-sectional vs. longitudinal) may significantly moderate the association between anxiety sensitivity and PTSD severity. No moderation effect was found for assessment of PTSD through interview versus questionnaire, interpersonal versus non-interpersonal trauma, or low versus high study quality. Such patterns of results are consistent with cognitive models of PTSD. Clinical implications, strengths and limitations of the review were discussed.

Exposure to continuous political violence: rational and experiential thinking styles, coping styles and post traumatic stress symptoms

Cognitive style is considered an important determinant of individual behavior. The aim of the present study was to examine the relations between rational and experiential thinking styles, coping styles and Post Traumatic Stress (PTS) symptoms among civilians exposed to continuous and ongoing exposure to political violence. Three-hundred and thirty-two Israeli adult citizens living in the south region of Israel reported on their experiences of exposure to political violence as well as level of PTS, coping styles, and preference toward rational and experiential processing style. Results showed that low rational thinking was related with elevated PTS, both directly and indirectly through the mediation of high emotion-focused coping. The findings suggest that rational thinking may serve as a protective factor against stress related to chronic exposure to political violence; conversely, a preference for low rationality may be a risk factor.

Lifetime adversity interacts with peritraumatic data-driven processing to predict intrusive memories

BACKGROUND AND OBJECTIVES

Although most trauma survivors experience some intrusive recollections of the traumatic event, only few subsequently develop posttraumatic stress disorder (PTSD). A well-established proximal risk-factor predictive of post-trauma psychopathology is peritraumatic cognitive processing. Another, more distal risk-factor is pre-trauma lifetime adversity. The present experimental analogue study tested the hypothesis that pre-trauma lifetime adversity interacts with peritraumatic perceptual (i.e., data-driven) processing to predict intrusive memory development.

METHODS

Fifty-three young adult women (non-clinical sample) indicated how much data-driven and conceptual processing they had engaged in while watching aversive film-clips (i.e., analogue trauma). On the subsequent three days, they reported intrusions of those clips. Moderation analyses tested for an interaction effect between lifetime adversity and data-driven processing in predicting intrusion load (number of intrusions weighted for their overall distress).

RESULTS

Increased data-driven processing predicted intrusion load primarily in individuals reporting more than three lifetime adversities, explaining 55% of variance. No such relationship was found for conceptual processing.

LIMITATIONS

Present analogue findings have yet to be replicated in a clinical population. Moreover, the conceptual processing scale was restricted by low internal consistency.

CONCLUSION

Present findings support the idea that intrusions are the result of poorly elaborated and primarily perceptually-formed memory traces; however, this was primarily the case in vulnerable individuals reporting several lifetime adversities. Results replicate the importance of peritraumatic processing in intrusion development but additionally point to a moderating effect of lifetime adversity.

Angiotensin involvement in trauma processing-exploring candidate neurocognitive mechanisms of preventing post-traumatic stress symptoms

The angiotensin-II antagonist losartan is a promising candidate that has enhanced extinction in a post-traumatic stress disorder (PTSD) animal model and was related to reducing PTSD symptom development in humans. Here, we investigate the neurocognitive mechanisms underlying these results, testing the effect of losartan on data-driven and contextual processing of traumatic material, mechanisms proposed to be relevant for PTSD development. In a double-blind between-subject design, 40 healthy participants were randomised to a single oral dose of losartan (50 mg) or placebo, 1 h before being exposed to distressing films as a trauma analogue while heart rate (HR) was measured. Peritraumatic processing was investigated using blurry picture stimuli from the films, which transformed into clear images. Data-driven processing was measured by the level of blurriness at which contents were recognised. Contextual processing was measured as the amount of context information retrieved when describing the pictures' contents. Negative-matched control images were used to test perceptual processing of peripheral trauma-cues. Post-traumatic stress symptoms were assessed via self-report questionnaires after analogue trauma and an intrusion diary completed over 4 days following the experiment. Compared to placebo, losartan facilitated contextual processing and enhanced detail perception in the negative-match pictures. During the films, the losartan group recorded lower HR and higher HR variability, reflecting lower autonomic stress responses. We discuss potential mechanisms of losartan in preventing PTSD symptomatology, including the role of reduced arousal and increased contextual processing during trauma exposure, as well as increased threat-safety differentiation when encountering peripheral trauma-cues in the aftermaths of traumatic events.

Improving mental health and physiological stress responses in mothers following traumatic childbirth and in their infants: study protocol for the Swiss TrAumatic biRth Trial (START)

INTRODUCTION

Emergency caesarean section (ECS) qualifies as a psychological trauma, which may result in postnatal post-traumatic stress disorder (PTSD). Maternal PTSD may not only have a significant negative impact on mother-infant interactions, but also on long-term infant development. The partner's mental health may also affect infant development. Evidence-based early interventions to prevent the development of postpartum PTSD in mothers are lacking. Immediately after a traumatic event, memory formation is vulnerable to interference. There is accumulating evidence that a brief behavioural intervention including a visuospatial task may result in a reduction in intrusive memories of the trauma.

METHODS AND ANALYSIS

This study protocol describes a double-blind multicentre randomised controlled phase III trial testing an early brief maternal intervention including the computer game 'Tetris' on intrusive memories of the ECS trauma (≤1 week) and PTSD symptoms (6 weeks, primary outcome) of 144 women following an ECS. The intervention group will carry out a brief behavioural procedure including playing Tetris. The attention-placebo control group will complete a brief written activity log. Both simple cognitive tasks will be completed within the first 6 hours following traumatic childbirth. The intervention is delivered by midwives/nurses in the maternity unit.The primary outcome will be differences in the presence and severity of maternal PTSD symptoms between the intervention and the attention-placebo control group at 6 weeks post partum. Secondary outcomes will be physiological stress and psychological vulnerability, mother-infant interaction and infant developmental outcomes. Other outcomes will be psychological vulnerability and physiological regulation of the partner and their bonding with the infant, as well as the number of intrusive memories of the event.

ETHICS AND DISSEMINATION

Ethical approval was granted by the Human Research Ethics Committee of the Canton de Vaud (study number 2017-02142). Dissemination of results will occur via national and international conferences, in peer-reviewed journals, public conferences and social media.

TRIAL REGISTRATION NUMBER

NCT03576586.

The effects of dual-tasks on intrusive memories following analogue trauma

Patients with post-traumatic stress disorder frequently and involuntarily experience intrusions, which are strongly linked to the trauma hotspot. Voluntary memory characteristics (i.e., vividness and unpleasantness) of this hotspot can be reduced by performing a dual-task, such as making horizontal eye movements, which is frequently used in Eye Movement Desensitization and Reprocessing. We tested whether such dual-task interventions would also reduce involuntary memory (i.e., intrusions). Moreover, we examined if changes in hotspot vividness and unpleasantness predicted intrusion frequency. Additionally, we examined whether the effects were dependent on dual-task modality. We tested this in three experiments. Participants watched a trauma film and performed one of the interventions 10-min post-film (1) Recall + Eye movements, (2) Recall + Counting, or (3) No-Task Control. Before and after the intervention, participants rated the hotspot vividness and unpleasantness. They recorded intrusive memories about the film in a diary for a week. Unexpectedly, we found that hotspot vividness and unpleasantness ratings were not affected by the intervention. However, the prolonged (experiment 2), but not standard (experiment 1), dual-task interventions resulted in a lower number of intrusions, regardless of modality. However, this effect was not replicated in experiment 3. We discuss potential explanations and present suggestions for future research.

Can't get it out of my mind: A systematic review of predictors of intrusive memories of distressing events

Intrusive memories, when persistent and distressing, are theorized to underlie a range of transdiagnostic psychological symptoms and associated impairment. However, little is known about factors predicting the development and persistence of intrusive memories. The aim of this systematic review is to evaluate the literature on pre-event, event-based, and post-event predictors of intrusive memories. A systematic review was conducted, searching for studies that examined intrusive, event-based memories. One hundred and six articles were identified from PsycInfo, PubMed, and Medline databases. Experimental and prospective studies with clinical (N = 14) and nonclinical (N = 92) samples were critically reviewed, provided the inclusion of an analogue stressor with nonclinical samples, and that intrusive memories frequency and/or distress were assessed as primary dependent variables. Pre-existing psychopathology and pre-event appraisal style appear to predict intrusive memories (small to medium effects), whereas trait dissociation did not predict intrusive memories. Of studies examining event-based predictors, higher data-driven processing appears to predict intrusive memories with generally large effects. Post-event negative appraisals consistently predicted intrusive memories (medium to large effects), and preliminary evidence suggests higher post-event conceptual processing predicting fewer intrusive memories. This review synthesizes findings regarding a broad range of pre-event, event-based, and post-event factors that may influence the development of intrusive memories. Methodological issues of current paradigms and the lack of emphasis on memory retrieval processes limit our understanding of what predicts intrusive memory persistence. These limitations are particularly important given that individuals typically seek treatment for distressing intrusive memories once a memory has been fully consolidated, where retrieval processes are of utmost importance. (PsycINFO Database Record

Frightened by the perpetrator's voice: Startle responsivity and cognitive processing predict earwitness speaker identification

This study was inspired by the case of a robbery victim who was startled and reminded of the crime upon hearing a stranger's voice, while not clearly recognizing the speaker. To investigate whether specific voices can modulate startle reactions and thereby predict speaker identification, we presented an audio hijack scenario to 84 participants and afterwards asked them to identify the perpetrator among neutral and negative speech fragments, while measuring flash-evoked eye-blink startle responses. Furthermore, we addressed data-driven cognitive processing during the audio scenario as a potential moderator in voice discrimination. Negative speech and the perpetrator's voice led to potentiated startle. Enhanced startle was positively associated with voice discrimination, but only in neutral speech fragments. In negative fragments, this association was weakened as a function of self-reported levels of data-driven processing during encoding. Thus, startle responses can generally predict accurate voice recognition, but speech emotionality and cognitive processing moderate this relationship.

Playing the computer game Tetris prior to viewing traumatic film material and subsequent intrusive memories: Examining proactive interference

BACKGROUND AND OBJECTIVES

Visuospatial working memory (WM) tasks performed concurrently or after an experimental trauma (traumatic film viewing) have been shown to reduce subsequent intrusive memories (concurrent or retroactive interference, respectively). This effect is thought to arise because, during the time window of memory consolidation, the film memory is labile and vulnerable to interference by the WM task. However, it is not known whether tasks before an experimental trauma (i.e. proactive interference) would also be effective. Therefore, we tested if a visuospatial WM task given before a traumatic film reduced intrusions. Findings are relevant to the development of preventative strategies to reduce intrusive memories of trauma for groups who are routinely exposed to trauma (e.g. emergency services personnel) and for whom tasks prior to trauma exposure might be beneficial.

METHODS

Participants were randomly assigned to 1 of 2 conditions. In the Tetris condition (n = 28), participants engaged in the computer game for 11 min immediately before viewing a 12-min traumatic film, whereas those in the Control condition (n = 28) had no task during this period. Intrusive memory frequency was assessed using an intrusion diary over 1-week and an Intrusion Provocation Task at 1-week follow-up. Recognition memory for the film was also assessed at 1-week.

RESULTS

Compared to the Control condition, participants in the Tetris condition did not report statistically significant difference in intrusive memories of the trauma film on either measure. There was also no statistically significant difference in recognition memory scores between conditions.

LIMITATIONS

The study used an experimental trauma paradigm and findings may not be generalizable to a clinical population.

CONCLUSIONS

Compared to control, playing Tetris before viewing a trauma film did not lead to a statistically significant reduction in the frequency of later intrusive memories of the film. It is unlikely that proactive interference, at least with this task, effectively influences intrusive memory development. WM tasks administered during or after trauma stimuli, rather than proactively, may be a better focus for intrusive memory amelioration.

Intrusive Memories of Distressing Information: An fMRI Study

Although intrusive memories are characteristic of many psychological disorders, the neurobiological underpinning of these involuntary recollections are largely unknown. In this study we used functional magentic resonance imaging (fMRI) to identify the neural networks associated with encoding of negative stimuli that are subsequently experienced as intrusive memories. Healthy partipants (N = 42) viewed negative and neutral images during a visual/verbal processing task in an fMRI context. Two days later they were assessed on the Impact of Event Scale for occurrence of intrusive memories of the encoded images. A sub-group of participants who reported significant intrusions (n = 13) demonstrated stronger activation in the amygdala, bilateral ACC and parahippocampal gyrus during verbal encoding relative to a group who reported no intrusions (n = 13). Within-group analyses also revealed that the high intrusion group showed greater activity in the dorsomedial (dmPFC) and dorsolateral prefrontal cortex (dlPFC), inferior frontal gyrus and occipital regions during negative verbal processing compared to neutral verbal processing. These results do not accord with models of intrusions that emphasise visual processing of information at encoding but are consistent with models that highlight the role of inhibitory and suppression processes in the formation of subsequent intrusive memories.

The impact of dissociation on perceptual priming and intrusions after listening to auditory narratives

This study investigates the causal role of dissociation in intrusive memory development and possible underlying aberrant memory processes (e.g., increased perceptual priming). Using an audio-only adaption of the trauma film paradigm, we divided 60 participants into 3 conditions and presented them with different visual tasks-mirror staring, dot staring, or neutral images. The former 2 conditions were hypothesized to induce dissociation. Postaudio, a number of factors were assessed, including state dissociation, perceptual priming and conceptual priming, as well as intrusions over 3 days. Participants in the dissociation conditions displayed an increase in perceptual priming compared to those in the control condition and reported more distressing intrusions. No differences were found in conceptual priming and the overall number of intrusions between conditions. Findings contribute to the growing knowledge on the impact of dissociation and cognitive processing in the etiology of posttraumatic stress disorder intrusions.

Enhanced association between perceptual stimuli and trauma-related information in individuals with posttraumatic stress disorder symptoms

BACKGROUND AND OBJECTIVES

Intrusive memories in traumatized individuals are often triggered by stimuli that are perceptually (rather than conceptually) similar to those present just before or during the trauma. The present study examined whether those individuals with high levels of Posttraumatic Stress Disorder (PTSD) symptoms show a memory bias recall to perceptual cues and trauma target words compared to those with low levels of PTSD.

METHODS

The sample consisted of 30 adult participants who were involved in motor-vehicle or work-related accidents; 15 of the participants endorsed clinically elevated symptoms of PTSD, while a comparison group of 15 participants reported low levels of symptoms. Participants performed an associative recognition task with conceptual or perceptual cue words and trauma-related or neutral target words. Participants were tested for their recognition accuracy by reporting the corresponding target when a cue was given.

RESULTS

Both groups performed better for the perceptual word pairs than for the conceptual word pairs, irrespective of the target word type. However, only the high PTSD symptoms group exhibited an additional enhancement in performance for the perceptual word pairs with trauma-related target words.

LIMITATIONS

A nonclinical sample was utilized for this study; although PTSD was assessed, diagnoses were not confirmed. In addition, there was lack of a healthy non-traumatized control group.

CONCLUSIONS

These results provide partial support for the cognitive model and the notion that intrusive memories are specific to the trauma-related event rather than to a general associative learning bias.

Cortisol response mediates the effect of post-reactivation stress exposure on contextualization of emotional memories

Retrieval of traumatic experiences is often accompanied by strong feelings of distress. Here, we examined in healthy participants whether post-reactivation stress experience affects the context-dependency of emotional memory. First, participants studied words from two distinctive emotional categories (i.e., war and disease) presented against a category-related background picture. One day later, participants returned to the lab and received a reminder of the words of one emotional category followed by exposure to a stress task (Stress group, n=22) or a control task (Control group, n=24). Six days later, memory contextualization was tested using a word stem completion task. Half of the word stems were presented against the encoding context (i.e., congruent context) and the other half of the word stems were presented against the other context (i.e., incongruent context). The results showed that participants recalled more words in the congruent context than in the incongruent context. Interestingly, cortisol mediated the effect of stress exposure on memory contextualization. The stronger the post-reactivation cortisol response, the more memory performance relied on the contextual embedding of the words. Taken together, the current findings suggest that a moderate cortisol response after memory reactivation might serve an adaptive function in preventing generalization of emotional memories over contexts.

Heart rate, startle response, and intrusive trauma memories

The current study adopted the trauma film paradigm to examine potential moderators affecting heart rate (HR) as an indicator of peritraumatic psychological states and as a predictor of intrusive memories. We replicated previous findings that perifilm HR decreases predicted the development of intrusive images and further showed this effect to be specific to images rather than thoughts, and to detail rather than gist recognition memory. Moreover, a group of individuals showing both an atypical sudden reduction in HR after a startle stimulus and higher trait dissociation was identified. Only among these individuals was lower perifilm HR found to indicate higher state dissociation, fear, and anxiety, along with reduced vividness of intrusions. The current findings emphasize how peritraumatic physiological responses relate to emotional reactions and intrusive memory. The moderating role of individual difference in stress defense style was highlighted.

Perceptual processing during trauma, priming and the development of intrusive memories

BACKGROUND

Intrusive reexperiencing in posttraumatic stress disorder (PTSD) is commonly triggered by stimuli with perceptual similarity to those present during the trauma. Information processing theories suggest that perceptual processing during the trauma and enhanced perceptual priming contribute to the easy triggering of intrusive memories by these cues.

METHODS

Healthy volunteers (N = 51) watched neutral and trauma picture stories on a computer screen. Neutral objects that were unrelated to the content of the stories briefly appeared in the interval between the pictures. Dissociation and data-driven processing (as indicators of perceptual processing) and state anxiety during the stories were assessed with self-report questionnaires. After filler tasks, participants completed a blurred object identification task to assess priming and a recognition memory task. Intrusive memories were assessed with telephone interviews 2 weeks and 3 months later.

RESULTS

Neutral objects were more strongly primed if they occurred in the context of trauma stories than if they occurred during neutral stories, although the effect size was only moderate [Formula: see text] and only significant when trauma stories were presented first. Regardless of story order, enhanced perceptual priming predicted intrusive memories at 2-week follow-up (N = 51), but not at 3 months (n = 40). Data-driven processing, dissociation and anxiety increases during the trauma stories also predicted intrusive memories. Enhanced perceptual priming and data-driven processing were associated with lower verbal intelligence.

LIMITATIONS

It is unclear to what extent these findings generalize to real-life traumatic events and whether they are specific to negative emotional events.

CONCLUSIONS

The results provide some support for the role of perceptual processing and perceptual priming in reexperiencing symptoms.

Is it mere distraction? Peri-traumatic verbal tasks can increase analogue flashbacks but reduce voluntary memory performance

Several experiments have shown that we can reduce the frequency of analogue flashbacks with competing tasks presented during a trauma film (i.e. peri-traumatically). A "distraction" hypothesis suggests that any competing task may reduce flashbacks due to distraction and/or a load on executive control. Alternatively, a "modality" hypothesis based on clinical models of PTSD suggests that certain tasks will not protect against intrusions (Experiment 1) and could actually increase them (Experiment 2). Experiment 1 contrasted two concurrent tasks, Verbal Interference (counting backwards in threes) and Visuospatial tapping, against a no-task Control condition during trauma film viewing. The Visuospatial group had significantly fewer intrusions of the film over 1-week than the Control group. Contrary to a distraction account, the Verbal Interference group did not show this effect. Using a larger sample, Experiment 2 showed that the Verbal Interference group (counting backwards in sevens) had more intrusions (and inferior voluntary memory) than no-task Controls. We propose that this is in line with a modality hypothesis concerning trauma flashbacks. Disrupting verbal/conceptual processing during trauma could be harmful for later flashbacks.

The Effects of Conceptual Processing Versus Suppression on Analogue PTSD Symptoms after a Distressing Film

Background:Researchers have begun to scrutinize the assumption that active processing in response to a traumatic event is beneficial whereas avoidance of thoughts, emotions and reminders about the traumatic event is detrimental. Indications that avoidance is not always detrimental come from studies on grief and debriefing.Aims:In an analogue experimental study, the hypothesis was tested that conceptually-driven processing immediately after a distressing film is more successful in reducing analogue PTSD symptoms than suppression of thoughts and images related to the film.Method:Ninety students watched a distressing film after which they were instructed to either elaborate on the meaning of the film (conceptual processing) (n= 31), suppress all thoughts and images of the film by performing a task (n= 29), or were given no instruction (n= 30). Four hours later, analogue PTSD symptoms were assessed.Results:The results showed that conceptually-driven processing does not result in fewer analogue PTSD symptoms than suppression.Conclusions:It is speculated that suppression may only be dysfunctional when individuals interpret their symptoms negatively or when suppression is believed to be dysfunctional.

Perceptual and conceptual processing as predictors of treatment outcome in PTSD

Cognitive behavioural treatment (CBT) is highly effective in treating post-traumatic stress disorder (PTSD). However, the mechanisms of change are still poorly understood. The aim of the present study was to investigate trauma processing during and after CBT for PTSD. Treatment consisted of imaginal exposure combined with rescripting. The rationale of this treatment is that dysfunctional interpretations may best be corrected by inducing new perspectives on what happened during trauma by experiencing new views and new emotions. In twenty-five chronic patients with PTSD, we tested whether an initial increase of perceptual processing and a subsequent increase of conceptual processing predicted treatment outcome. Possible changes in perceptual/conceptual processing during and after treatment were inferred from changes in trauma memories from pre- to post-treatment and from post- to 1-month follow-up. These memory parameters were assessed by analysing trauma narratives that were produced before the first treatment session, after the last treatment session and at follow-up. Consistent with predictions, a relative increase of conceptual processing after treatment predicted treatment outcome levels for both PTSD symptoms and general psychopathology at 1-month follow-up. Although a relative increase of perceptual processing during treatment also predicted treatment outcome, this effect was explained by the beneficial effect of a subsequent increase of conceptual processing. But an increase of perceptual processing during treatment was strongly related to an increase of conceptual processing after treatment. The results suggest that imaginal reliving during CBT is not crucial for symptom reduction, but it may promote conceptual processing, which in itself predicts a better treatment outcome.