Perturbed threat monitoring following a traumatic event predicts risk for post-traumatic stress disorder

What Are the Predictors of Post-traumatic Stress Disorder Among Road Traffic Accident Survivors: A Systematic Review

ABSTRACT

Traffic accidents put tremendous burdens on the psychosocial aspects of communities. Post-traumatic stress disorder (PTSD), after an accident, is one of the most prevalent and incapacitating psychiatric conditions worldwide. In this systematic review, we aimed to investigate the predictors of PTSD in traffic accident victims. Primary search was conducted in November 2021 and updated in 2023. Studies were excluded if they used any analysis except regression for predictors. Cumulatively, primary and update searches retrieved 10,392 articles from databases, and of these, 87 studies were systematically reviewed. The predictors were categorized into sociodemographics, pretrauma, peritrauma, and post-trauma factors. The PTSD assessment time varied between 2 weeks and 3 years. Being a woman, having depression and having a history of road traffic accidents pretraumatically, peritraumatic dissociative experiences, acute stress disorder diagnosis, rumination, higher injury severity, and involvement in litigation or compensation after the trauma were significant predictors of PTSD.

Examining the role of trait anxiety and attentional bias to negative information in intrusion vulnerability following an emotionally negative event

BACKGROUND AND OBJECTIVES

Research shows that individuals with heightened trait anxiety are more likely to experience intrusions; however, the mechanism that accounts for this relationship is unclear. Two alternative hypotheses were tested to determine the nature of the associations between trait anxiety, attentional bias to negative information, and intrusion vulnerability.

METHODS

Intrusions were elicited using the trauma film paradigm, and post-event attentional bias to negative information was assessed using the dot-probe task. Participants then completed a week-long intrusions diary.

RESULTS

Results showed that attentional bias to negative information mediated the effect of heightened trait anxiety on elevated intrusion frequency. It was also revealed that heightened trait anxiety was associated with elevated intrusion-related distress, though attentional bias to negative information did not mediate this relationship.

LIMITATIONS

Our sample was comprised of undergraduate students who were not selected based on a previous pathology. Replication in clinical samples is warranted.

CONCLUSIONS

These findings provide new insight regarding individual differences in the experience of intrusions and suggest that both the frequency and distress associated with intrusions could represent clinical targets.

Experimental control of conflict in a predictive visual probe task: Highly reliable bias scores related to anxiety

Concerns have been raised about the low reliability of measurements of spatial attentional bias via RT differences in dot-probe tasks. The anticipatory form of the bias, directed towards predicted future stimuli, appears to have relatively good reliability, reaching around 0.70. However, studies thus far have not attempted to experimentally control task-related influence on bias, which could further improve reliability. Evoking top-down versus bottom-up conflict may furthermore reveal associations with individual differences related to mental health. In the current study, a sample of 143 participants performed a predictive Visual Probe Task (predVPT) with angry and neutral face stimuli online. In this task, an automatic bias is induced via visually neutral cues that predict the location of an upcoming angry face. A task-relevant bias was induced via blockwise shifts in the likely location of target stimuli. The bias score resulting from these factors was calculated as RTs to target stimuli at locations of predicted but not actually presented angry versus neutral faces. Correlations were tested with anxiety, depression, self-esteem and aggression scales. An overall bias towards threat was found with a split-half reliability of 0.90, and 0.89 after outlier removal. Avoidance of threat in blocks with a task-relevant bias away from threat was correlated with anxiety, with correction for multiple testing. The same relationship was nominally significant for depression and low self-esteem. In conclusion, we showed high reliability of spatial attentional bias that was related to anxiety.

Threat Bias and Emotion Recognition in Victims of IPV

Although there is growing evidence of the association between threat bias and psychopathology in many trauma-exposed populations, there are few studies with intimate partner violence (IPV) victims. The present study assessed threat bias in IPV victims. It also examined potential differences in facial recognition ability between victims and nonvictims. Participants were 153 female college students currently in a dating relationship. Participants completed demographic and abuse severity measures. They then completed a dot-probe task to assess threat bias, and a facial expression recognition task to assess speed and accuracy of recognition. Approximately 32% of the students sampled were currently in a physically abusive relationship. Results indicated that IPV victims had a bias toward fearful faces, and showed worse recognition of happy faces than nonvictims. These data suggest that the psychological impact of threat bias might vary temporally. Vigilance during threat may serve as a protective mechanism, whereas postthreat vigilance might be associated with psychopathology. Researchers should carefully consider the presence of threat bias in victim samples and include other victim groups in future assessments of threat bias. It will be important to test these relationships in other IPV victim samples, such as help-seeking victims and other community living victims.

A systematic review of the association between fault or blame-related attributions and procedures after transport injury and health and work-related outcomes

Attributions of fault are often associated with worse injury outcomes; however, the consistency and magnitude of these impacts is not known. This review examined the prognostic role of fault on health, mental health, pain and work outcomes after transport injury. A systematic search of five electronic databases (Medline, Embase, CINAHL, PsycINFO, Cochrane Library) yielded 16,324 records published between 2000 and January 2018. Eligibility criteria were: adult transport injury survivors; prospective design; multivariable analysis; fault-related factor analysed; pain, mental health, general health or work-related outcome. Citations (n = 10,558, excluding duplicates) and full text articles (n = 555) were screened manually (Reviewer 1), and using concurrent machine learning and text mining (Reviewer 2; using Abstrackr, WordStat and QDA miner). Data from 55 papers that met all inclusion criteria were extracted, papers were evaluated for risk of bias using the QUIPS tool, and overall level of evidence was assessed using the GRADE tool. There were six main fault-related factors classified as: fault or responsibility, fault-based compensation, lawyer involvement or litigation, blame or guilt, road user or position in vehicle, and impact direction. Overall there were inconsistent associations between fault and transport injury outcomes, and 60% of papers had high risk of bias. There was moderate evidence that fault-based compensation claims were associated with poorer health-related outcomes, and that lawyer involvement was associated with poorer work outcomes beyond 12 months post-injury. However, the evidence of negative associations between fault-based compensation claims and work-related outcomes was limited. Lawyer involvement and fault-based compensation claims were associated with adverse mental health outcomes six months post-injury, but not beyond 12 months. The most consistent associations between fault and negative outcomes were not for fault attributions, per se, but were related to fault-related procedures (e.g., lawyer engagement, fault-based compensation claims).

Validity of Attention Bias Variability Indices for Posttraumatic Stress Disorder Research: Evidence From Patient Data

Although initial findings indicated that threat-related attention bias variability (ABV), an index designed to capture dynamic shifts in threat-related attention over time, was positively correlated with the severity of posttraumatic stress disorder (PTSD) symptoms, a recent study relying on simulated data has raised questions regarding the validity and empirical utility of ABV. Specifically, the simulations suggested that core features of reaction time data distinct from threat-related attention bias, such as the reaction time standard deviation and mean, could explicate the reported elevated ABV among samples with PTSD. In the present study, we evaluated these suggestions in 95 PTSD-diagnosed participants. The results showed that ABV significantly and uniquely predicted PTSD symptom severity beyond the predictive value of core reaction time features, ΔR² = .05-.23. Some of the predictions stemming from the simulated results were replicated, whereas others were not. Contrary to the conclusion drawn from the simulated data, the results from the current study suggest that ABV is a valid and replicable correlate of PTSD symptom severity.

Computational Modeling Applied to the Dot-Probe Task Yields Improved Reliability and Mechanistic Insights

BACKGROUND

Biased patterns of attention are implicated as key mechanisms across many forms of psychopathology and have given rise to automated mechanistic interventions designed to modify such attentional preferences. However, progress is substantially hindered by limitations in widely used methods to quantify attention, bias leading to imprecision of measurement.

METHODS

In a sample of patients who were clinically anxious (n = 70), we applied a well-validated form of computational modeling (drift-diffusion model) to trial-level reaction time data from a two-choice "dot-probe task"-the dominant paradigm used in hundreds of attention bias studies to date-in order to model distinct components of task performance.

RESULTS

While drift-diffusion model-derived attention bias indices exhibited convergent validity with previous approaches (e.g., conventional bias scores, eye tracking), our novel analytic approach yielded substantially improved split-half reliability, modestly improved test-retest reliability, and revealed novel mechanistic insights regarding neural substrates of attention bias and the impact of an automated attention retraining procedure.

CONCLUSIONS

Computational modeling of attention bias task data may represent a new way forward to improve precision.

Emotional intelligence in patients with posttraumatic stress disorder, borderline personality disorder and healthy controls

Emotional intelligence as a part of social cognition has, to our knowledge, never been investigated in patients with Posttraumatic Stress Disorder (PTSD), though the disorder is characterized by aspects of emotional dysfunctioning. PTSD often occurs with Borderline Personality Disorder (BPD) as a common comorbidity. Studies about social cognition and emotional intelligence in patients with BPD propose aberrant social cognition, but produced inconsistent results regarding emotional intelligence. The present study aims to assess emotional intelligence in patients with PTSD without comorbid BPD, PTSD with comorbid BPD, and BPD patients without comorbid PTSD, as well as in healthy controls. 71 patients with PTSD (41 patients with PTSD without comorbid BPD, 30 patients with PTSD with comorbid BPD), 56 patients with BPD without PTSD, and 63 healthy controls filled in the Test of Emotional Intelligence (TEMINT). Patients with PTSD without comorbid BPD showed impairments in emotional intelligence compared to patients with BPD without PTSD, and compared to healthy controls. These impairments were not restricted to specific emotions. Patients with BPD did not differ significantly from healthy controls. This study provides evidence for an impaired emotional intelligence in PTSD without comorbid BPD compared to BPD and healthy controls, affecting a wide range of emotions.

When stress becomes the new normal: Alterations in attention and autonomic reactivity in repeated traumatization

There is need for further work clarifying attention-physiology interactions by degree of exposure to early victimization, as it is clear that cumulative trauma in childhood, that is, polyvictimization, may have lasting effects on the stress response that differ from those of acute traumatization. The present study examined relationships between baseline and task-related physiology (indexed by respiratory sinus arrhythmia [RSA] and heart rate [HR], respectively), and attention biases (via the dot probe task), in 63 community-dwelling adult women stratified on the basis of self-reported exposure to multiple types of childhood interpersonal victimization (i.e., sexual, physical, and emotional abuse). Consistent with hypotheses, a pattern of threat hypervigilance was found in the single victimization group, while threat avoidance was found in the polyvictimization group. Additionally, avoidance of threat in the polyvictimized group was associated with lower baseline RSA. Moderation analyses indicated that condition-wise HR moderated the relationship between level of exposure and attention biases in the high-threat condition. The present findings may clarify basic regulatory mechanisms that play a role in lifetime revictimization in individuals with cumulative childhood trauma exposure and may have implications for their prognostic and therapeutic outcomes.

Different attention bias patterns in anorexia nervosa restricting and binge/purge types

Patients with anorexia nervosa (AN) have been shown to display both elevated anxiety and attentional biases in threat processing. In this study, we compared threat-related attention patterns of patients with AN restricting type (AN-R; n = 32), AN binge/purge type (AN-B/P; n = 23), and healthy controls (n = 19). A dot-probe task with either eating disorder-related or general and social anxiety-related words was used to measure attention patterns. Severity of eating disorder symptoms, depression, anxiety, and stress were also assessed. Patients with AN-R showed vigilance to both types of threat words, whereas patients with AN-B/P showed avoidance of both threat types. Healthy control participants did not show any attention bias. Attention bias was not associated with any of the demographic, clinical, and psychometric parameters introduced. These findings suggest that there are differential patterns of attention allocation in patients with AN-R and AN-B/P. More research is needed to identify what causes/underlies these differential patterns.

Prevalence of posttraumatic stress disorder among road traffic accident survivors: A PRISMA-compliant meta-analysis

BACKGROUND

Involvement in road traffic accidents (RTAs) may put individuals at increased risk for a wide range of psychiatric disorders, among which posttraumatic stress disorder (PTSD) presents a public health issue. However, a great disparity was observed among studies exploring the prevalence of PTSD among RTA survivors. This meta-analysis aimed to explore the pooled prevalence of PTSD among RTA survivors.

METHODS

Electronic databases of PubMed, Embase, Web of Science, PsycARTICLES, PsycINFO, and CINAHL were searched to identify relevant studies. Study selection and data extraction were conducted independently by 2 investigators, and a meta-analysis was performed to synthesize the data. Heterogeneity among studies was evaluated using the Cochran Q test and quantified using the I statistic. Subgroup analyses were performed to identify the source of the heterogeneity. The possibility of publication bias was assessed using Egger linear test.

RESULTS

Fifteen eligible studies containing 6804 RTA survivors were identified in this meta-analysis, of which 1489 were identified with PTSD. The pooled prevalence of PTSD among RTA survivors was 22.25% (95% confidence interval: 16.71%-28.33%). A high degree of heterogeneity was observed across studies (I = 97.1%, P < .001), with reported PTSD prevalence ranging from 6.3% to 58.3%. Subgroup analyses found that the prevalence of PTSD among RTA survivors varied significantly across studies in relation to the instrument used to assess PTSD, country, race, gender, and education level (P < .05).

CONCLUSION

The high pooled prevalence of PTSD among RTA survivors found in this study significantly underscores the need for providing timely and effective intervention strategies for RTA survivors.

Less is more: Patient-level meta-analysis reveals paradoxical dose-response effects of a computer-based social anxiety intervention targeting attentional bias

BACKGROUND

The past decade of research has seen considerable interest in computer-based approaches designed to directly target cognitive mechanisms of anxiety, such as attention bias modification (ABM).

METHODS

By pooling patient-level datasets from randomized controlled trials of ABM that utilized a dot-probe training procedure, we assessed the impact of training "dose" on relevant outcomes among a pooled sample of 693 socially anxious adults.

RESULTS

A paradoxical effect of the number of training trials administered was observed for both posttraining social anxiety symptoms and behavioral attentional bias (AB) toward threat (the target mechanism of ABM). Studies administering a large (>1,280) number of training trials showed no benefit of ABM over control conditions, while those administering fewer training trials showed significant benefit for ABM in reducing social anxiety (P = .02). These moderating effects of dose were not better explained by other examined variables and previously identified moderators, including patient age, training setting (laboratory vs. home), or type of anxiety assessment (clinician vs. self-report).

CONCLUSIONS

Findings inform the optimal dosing for future dot-probe style ABM applications in both research and clinical settings, and suggest several novel avenues for further research.

Associations Among Posttraumatic Stress Disorder Symptoms, Substance Use, and Affective Attentional Processing in OEF/OIF/OND Veterans

The majority of research examining affective attentional bias in posttraumatic stress disorder (PTSD) has not examined the influence of co-occurring psychiatric disorders. This study examined the individual and interactive effects of PTSD symptoms and substance use disorders (SUDs) on affective attentional processing among 323 veterans deployed to Iraq or Afghanistan. Participants were divided into those with SUD (SUD+, n = 46) and those without (SUD-, n = 277). Substance use disorder was determined using the Structured Clinical Interview for DSM-IV. Posttraumatic stress disorder was measured using the Clinician Administered PTSD Scale. A computerized go/no-go task (Robbins et al., 1994, Robbins et al.,1998) assessed affective attentional processing. Relative to those without SUD, those with SUD showed a significant association between PTSD symptoms and increased omission and commission accuracy rates and decreased d prime. No effects of valence were found. Findings suggest the need to consider co-occurring SUD when investigating the effects of PTSD on attentional control.

Modification of cognitive biases related to posttraumatic stress: A systematic review and research agenda

Cognitive models of Posttraumatic Stress Disorder (PTSD) postulate that cognitive biases in attention, interpretation, and memory represent key factors involved in the onset and maintenance of PTSD. Developments in experimental research demonstrate that it may be possible to manipulate such biases by means of Cognitive Bias Modification (CBM). In the present paper, we summarize studies assessing cognitive biases in posttraumatic stress to serve as a theoretical and methodological background. However, our main aim was to provide an overview of the scientific literature on CBM in (analogue) posttraumatic stress. Results of our systematic literature review showed that most CBM studies targeted attentional and interpretation biases (attention: five studies; interpretation: three studies), and one study modified memory biases. Overall, results showed that CBM can indeed modify cognitive biases and affect (analog) trauma symptoms in a training congruent manner. Interpretation bias procedures seemed effective in analog samples, and memory bias training proved preliminary success in a clinical PTSD sample. Studies of attention bias modification provided more mixed results. This heterogeneous picture may be explained by differences in the type of population or variations in the CBM procedure. Therefore, we sketched a detailed research agenda targeting the challenges for CBM in posttraumatic stress.

Accessible Neurobehavioral Anger-Related Markers for Vulnerability to Post-Traumatic Stress Symptoms in a Population of Male Soldiers

Identifying vulnerable individuals prone to develop post-traumatic stress symptoms (PTSS) is of paramount importance, especially in populations at high risk for stress exposure such as combat soldiers. While several neural and psychological risk factors are known, no post-traumatic stress disorder (PTSD) biomarker has yet progressed to clinical use. Here we present novel and clinically applicable anger-related neurobehavioral risk markers for military-related PTSS in a large cohort of Israeli soldiers. The psychological, electrophysiological and neural (Simultaneous recording of scalp electroencephalography [EEG] and functional magnetic resonance imaging [fMRI]) reaction to an anger-inducing film were measured prior to advanced military training and PTSS were recorded at 1-year follow-up. Limbic modulation was measured using a novel approach that monitors amygdala modulation using fMRI-inspired EEG, hereafter termed amygdala electrical fingerprint (amyg-EFP). Inter-subject correlation (ISC) analysis on fMRI data indicated that during movie viewing participants' brain activity was synchronized in limbic regions including the amygdala. Self-reported state-anger and amyg-EFP modulation successfully predicted PTSS levels. State-anger significantly accounted for 20% of the variance in PTSS, and amyg-EFP signal modulation significantly accounted for additional 15% of the variance. Our study was limited by the moderate PTSS levels and lack of systematic baseline symptoms assessment. These results suggest that pre-stress neurobehavioral measures of anger may predict risk for later PTSS, pointing to anger-related vulnerability factors that can be measured efficiently and at a low cost before stress exposure. Possible mechanisms underlying the association between the anger response and risk for PTSS are discussed.

ATTENTIONAL BIAS TEMPORAL DYNAMICS PREDICT POSTTRAUMATIC STRESS SYMPTOMS: A PROSPECTIVE-LONGITUDINAL STUDY AMONG SOLDIERS

BACKGROUND

Attentional bias (AB) to threat is thought to play a key role in the development and maintenance of posttraumatic stress symptomatology (PTS). Empirical evidence though is inconsistent. Some studies report associations between AB towards, threat and PTS; other studies report associations between AB away from threat and PTS; yet other studies fail to find any association. We propose that prospective-longitudinal study of AB as a dynamic process, expressed from moment to moment in time, may help to understand these mixed findings and the role of AB in PTS.

METHODS

We tested cross-sectional and prospective-longitudinal associations between AB and PTS among German soldiers from pre- to post-deployment in Afghanistan (n = 144). AB to threat and positive emotion stimuli (angry/happy faces) was measured using the dot-probe task. PTS was assessed by the PTSD Checklist. The number of traumatic experiences was assessed using CIDI-traumatic experience lists for military.

RESULTS

We found that AB dynamics (i.e., towards, away, temporal variability) at pre- and post-deployment, with respect to angry and happy faces, predicted higher levels of PTS after deployment as a function of number of intermediate traumatic experiences. Traditional aggregated mean bias scores did not similarly prospectively predict PTS post deployment.

CONCLUSIONS

Findings indicate that AB to emotionally arousing stimuli may play an important function in the development and maintenance of PTS. We argue that mixed and null findings appear to be due to failure to model the within-subject temporal variability in AB expression. Theoretical, empirical, and clinical implications of these findings are discussed.

Cognitive Load Undermines Thought Suppression in Acute Stress Disorder

Thought suppression studies demonstrate that attempts to suppress can be undermined by cognitive load. We report the first instance in which this has been tested experimentally in a sample of recently traumatized individuals. Individuals with and without acute stress disorder (ASD) were recruited following recent trauma and randomized to load or no load conditions (N=56). They monitored intrusive memories during baseline, suppression, and think anything phases. The impact of suppression and load on self-reported intrusions, attention bias (dot-probe), and memory priming (word-stem task) was assessed. The ASD load group were less able to suppress memories (d=0.32, CI95 [-0.15, 0.83], p=.088) than the ASD no load group (d=0.63, CI95 [0.08, 1.24], p<.001). In the think anything phase, the ASD load group reported more intrusions than the ASD no load or non-ASD groups (with and without load). No consistent findings were observed in relation to attentional bias. ASD load individuals exhibited stronger priming responses for motor vehicle accident and assault words than all other groups (ds between 0.35-0.73). Working memory did not moderate any outcomes of interest. The findings indicate that cognitive load interferes with suppression and may enhance access to trauma memories and associated material. The study extends previous research by demonstrating these effects for the first time in a clinical sample of recent survivors of trauma.

Threat-Related Attention Bias Variability and Posttraumatic Stress

OBJECTIVE

Threat monitoring facilitates survival by allowing one to efficiently and accurately detect potential threats. Traumatic events can disrupt healthy threat monitoring, inducing biased and unstable threat-related attention deployment. Recent research suggests that greater attention bias variability, that is, attention fluctuations alternating toward and away from threat, occurs in participants with PTSD relative to healthy comparison subjects who were either exposed or not exposed to traumatic events. The current study extends findings on attention bias variability in PTSD.

METHOD

Previous measurement of attention bias variability was refined by employing a moving average technique. Analyses were conducted across seven independent data sets; in each, data on attention bias variability were collected by using variants of the dot-probe task. Trauma-related and anxiety symptoms were evaluated across samples by using structured psychiatric interviews and widely used self-report questionnaires, as specified for each sample.

RESULTS

Analyses revealed consistent evidence of greater attention bias variability in patients with PTSD following various types of traumatic events than in healthy participants, participants with social anxiety disorder, and participants with acute stress disorder. Moreover, threat-related, and not positive, attention bias variability was correlated with PTSD severity.

CONCLUSIONS

These findings carry possibilities for using attention bias variability as a specific cognitive marker of PTSD and for tailoring protocols for attention bias modification for this disorder.

Infant attachment predicts bodily freezing in adolescence: evidence from a prospective longitudinal study

Early life-stress, particularly maternal deprivation, is associated with long-lasting deviations in animals’ freezing responses. Given the relevance of freezing for stress-coping, translational research is needed to examine the relation between insecure infant-parent attachment and bodily freezing-like behavior in humans. Therefore, we investigated threat-related reductions in body sway (indicative of freezing-like behavior) in 14-year-old adolescents (N = 79), for whom attachment security was earlier assessed in infancy. As expected, insecure (vs. secure) attachment was associated with less body sway for angry vs. neutral faces. This effect remained when controlling for intermediate life events. These results suggest that the long-lasting effects of early negative caregiving experiences on the human stress and threat systems extend to the primary defensive reaction of freezing. Additionally, we replicated earlier work in adults, by observing a significant correlation (in adolescents assessed as securely attached) between subjective state anxiety and reduced body sway in response to angry vs. neutral faces. Together, this research opens venues to start exploring the role of freezing in the development of human psychopathology.