Threat-Related Attention Bias Variability and Posttraumatic Stress

Attentional bias and its temporal dynamics among war veterans suffering from chronic pain: Investigating the contribution of post-traumatic stress symptoms

BACKGROUND

Cognitive models propose that attentional dysregulation, including an attentional bias towards threat, is one of the factors through which chronic pain and post-traumatic stress symptoms (PTSS) maintain and exacerbate one another. The current investigation assessed the attentional bias for painful facial expressions and its relationship with PTSS, using both traditional and variability-based attentional bias measures, among veterans with chronic pain and PTSS and controls.

METHOD

Fifty-four veterans with chronic pain and 30 age/education-matched controls participated in this investigation. Participants completed a self-report measure of PTSS and a modified version of the dot-probe task with painful, happy, and neutral facial expressions. Attention was assessed using both traditional and variability-based reaction time measures of attentional bias.

RESULTS

Veterans directed attention away from painful facial expressions (i.e., avoidance) relative to both the control group (between-subject effect) and relative to neutral faces (within-subject effect). Veterans also showed significantly elevated attentional bias variability for both happy and painful facial expressions compared to controls. Attentional bias variability for happy and painful facial expressions was correlated with PTSS among all participants.

CONCLUSION

Veterans with chronic pain and PTSS avoided pain-related stimuli and displayed an overall attentional dysregulation for emotional facial expressions. Avoidance of pain cues may be a coping strategy that these individuals develop under stressful conditions. Implications, limitations, and directions for future research are discussed.

Internet-delivered computerized cognitive & affective remediation training for the treatment of acute and chronic posttraumatic stress disorder: Two randomized clinical trials

Treatment of posttraumatic stress disorder (PTSD) is time and cost-intensive. New, readily implementable interventions are needed. Two parallel randomized clinical trials tested if cognitive/affective computerized training improves cognitive/affective functions and PTSD symptoms in acute (N = 80) and chronic PTSD (N = 84). Adults age 18-65 were recruited from an Israeli hospital emergency room (acute) or from across the United States (chronic). Individuals were randomized to an active intervention (acute N = 50, chronic N = 48) that adaptively trains cognition and an affective positivity bias, or a control intervention (acute N = 30, chronic N = 36) of engaging computer games. Participants, blind to assignment, completed exercises at home for 30 min/day over 30 days (acute) or 45 min/day over 45 days (chronic). Primary outcomes were computerized cognitive/affective function metrics. Secondary outcomes were Clinician-Administered PTSD Scale (CAPS) total scores. In chronic PTSD, the active arm demonstrated facilitated speed of fearful face identification (F = 20.96, q < 0.001; d = 1.21) and a trend towards improvement in total PTSD symptoms (F = 2.91, p = 0.09, d = 0.47), which was due to improvement in re-experiencing symptoms (F = 6.14, p = 0.015; d = 0.73). Better cognitive performance at baseline moderated the training effect and was associated with more favorable improvements on both metrics. Cognitive and affective training does not have widespread benefit on symptoms and cognitive/affective functions in PTSD. Future studies targeting re-experiencing a priori, stratifying on cognitive capacity, and with modified methods to infer on mechanisms and optimized training parameters may be warranted. ClinicalTrials.gov Identifiers: NCT01694316 &NCT02085512.

Processing of affective words in adolescent PTSD-Attentional bias toward social threat

Post-traumatic stress disorder (PTSD) is associated with a hypersensitivity to potential threat. This hypersensitivity manifests through differential patterns of emotional information processing and has been demonstrated in behavioral and neurophysiological experimental paradigms. However, the majority of research has been focused on adult patients with PTSD. To examine possible differences in underlying neurophysiological patterns for adolescent patients with PTSD after childhood sexual and/or physical abuse (CSA/CPA), ERP correlates of emotional word processing in 38 healthy participants and 40 adolescent participants with PTSD after experiencing CSA/CPA were studied. The experimental paradigm consisted of a passive reading task with neutral, positive (e.g., paradise), physically threatening (e.g., torment), and socially threatening (i.e., swearing, e.g., son of a bitch) words. A modulation of P3 amplitudes by emotional valence was found, with positive words inducing less elevated amplitudes over both groups. Interestingly, in later processing, the PTSD group showed augmented early late positive potential (LPP) amplitudes for socially threatening stimuli, while there were no modulations within the healthy control group. Also, region-specific emotional modulations for anterior and posterior electrode clusters were found. For the anterior LPP, highest activations have been found for positive words, while socially and physically threatening words led to strongest modulations in the posterior LPP cluster. There were no modulations by group or emotional valence at the P1 and EPN stage. The findings suggest an enhanced conscious processing of socially threatening words in adolescent patients with PTSD after CSA/CPA, pointing to the importance of a disjoined examination of threat words in emotional processing research.

The effects of trauma on brain and body: A unifying role for the midbrain periaqueductal gray

Post-traumatic stress disorder (PTSD), a diagnosis that may follow the experience of trauma, has multiple symptomatic phenotypes. Generally, individuals with PTSD display symptoms of hyperarousal and of hyperemotionality in the presence of fearful stimuli. A subset of individuals with PTSD; however, elicit dissociative symptomatology (i.e., depersonalization, derealization) in the wake of a perceived threat. This pattern of response characterizes the dissociative subtype of the disorder, which is often associated with emotional numbing and hypoarousal. Both symptomatic phenotypes exhibit attentional threat biases, where threat stimuli are processed preferentially leading to a hypervigilant state that is thought to promote defensive behaviors during threat processing. Accordingly, PTSD and its dissociative subtype are thought to differ in their proclivity to elicit active (i.e., fight, flight) versus passive (i.e., tonic immobility, emotional shutdown) defensive responses, which are characterized by the increased and the decreased expression of the sympathetic nervous system, respectively. Moreover, active and passive defenses are accompanied by primarily endocannabinoid- and opioid-mediated analgesics, respectively. Through critical review of the literature, we apply the defense cascade model to better understand the pathological presentation of defensive responses in PTSD with a focus on the functioning of lower-level midbrain and extended brainstem systems.

Heterogeneity of the Anxiety-Related Attention Bias: A Review and Working Model for Future Research

The anxiety-related attention bias (AB) has been studied for several decades as a clinically-relevant output of the dynamic and complex threat detection-response system. Despite research enthusiasm for the construct of AB, current theories and measurement approaches cannot adequately account for the growing body of mixed, contradictory, and null findings. Drawing on clinical, neuroscience, and animal models, we argue that the apparent complexity and contradictions in the empirical literature can be attributed to the field's failure to clearly conceptualize AB heterogeneity and the dearth of studies in AB that consider additional cognitive mechanisms in anxiety, particularly disruptions in threat-safety discrimination and cognitive control. We review existing research and propose a working model of AB heterogeneity positing that AB may be best conceptualized as multiple subtypes of dysregulated processing of and attention to threat anchored in individual differences in threat-safety discrimination and cognitive control. We review evidence for this working model and discuss how it can be used to advance knowledge of AB mechanisms and inform personalized prevention and intervention approaches.

Anxiety-Linked Attentional Bias: Is It Reliable?

There is substantial evidence that heightened anxiety vulnerability is characterized by increased selective attention to threatening information. The reliability of this anxiety-linked attentional bias has become the focus of considerable recent interest. We distinguish between the potential inconsistency of anxiety-linked attentional bias and inconsistency potentially reflecting the psychometric properties of the assessment approaches used to measure it. Though groups with heightened anxiety vulnerability often exhibit, on average, elevated attention to threat, the evidence suggests that individuals are unlikely to each display a stable, invariant attentional bias to threat. Moreover, although existing assessment approaches can differentiate between groups, they do not exhibit the internal consistency or test-retest reliability necessary to classify individuals in terms of their characteristic pattern of attentional responding to threat. We discuss the appropriate uses of existing attentional bias assessment tasks and propose strategies for enhancing classification of individuals in terms of their tendency to display an attentional bias to threat.

Dispositional negativity, cognition, and anxiety disorders: An integrative translational neuroscience framework

When extreme, anxiety can become debilitating. Anxiety disorders, which often first emerge early in development, are common and challenging to treat, yet the underlying mechanisms have only recently begun to come into focus. Here, we review new insights into the nature and biological bases of dispositional negativity, a fundamental dimension of childhood temperament and adult personality and a prominent risk factor for the development of pediatric and adult anxiety disorders. Converging lines of epidemiological, neurobiological, and mechanistic evidence suggest that dispositional negativity increases the likelihood of psychopathology via specific neurocognitive mechanisms, including attentional biases to threat and deficits in executive control. Collectively, these observations provide an integrative translational framework for understanding the development and maintenance of anxiety disorders in adults and youth and set the stage for developing improved intervention strategies.

Attention to threat in posttraumatic stress disorder as indexed by eye-tracking indices: a systematic review

BACKGROUND

Cognitive models of posttraumatic stress disorder (PTSD) implicate threat-related attentional biases in the etiology and phenomenology of the disorder. However, extant attentional research using reaction time (RT)-based paradigms and measures has yielded mixed results. Eye-tracking methodology has emerged in recent years to overcome several inherent drawbacks of RT-based tasks, striving to better delineate attentional processes.

METHODS

A systematic review of experimental studies examining threat-related attention biases in PTSD, using eye-tracking methodology and group-comparison designs, was conducted conforming to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were selected following a systematic search for publications between 1980 and December 2017 in PsycINFO, MEDLINE and the National Center for PTSD Research's Published International Literature on Traumatic Stress (PILOTS) database. Additional records were identified by employing the Similar Articles feature in PubMed, and the Cited Reference Search in ISI Web of Science. Reference sections of review articles, book chapters and studies selected for inclusion were searched for further studies. Ongoing studies were also sought through Clinicaltrials.gov.

RESULTS

A total of 11 studies (n = 456 participants in total) were included in the final review. Results indicated little support for enhanced threat detection, hypervigilance and attentional avoidance. However, consistent evidence emerged for sustained attention on threat (i.e. attention maintenance) in PTSD.

CONCLUSIONS

This review is the first to systematically evaluate extant findings in PTSD emanating from eye-tracking studies employing group-comparison designs. Results suggest that sustained attention on threat might serve as a potential target for therapeutic intervention.

Threat-related Attention Bias in Socioemotional Development: A Critical Review and Methodological Considerations

Cross-sectional evidence suggests that attention bias to threat is linked to anxiety disorders and anxiety vulnerability in both children and adults. However, there is a lack of developmental evidence regarding the causal mechanisms through which attention bias to threat might convey risks for socioemotional problems, such as anxiety. Gaining insights into this question demands longitudinal research to track the complex interplay between threat-related attention and socioemotional functioning. Developing and implementing reliable and valid assessments tools is essential to this line of work. This review presents theoretical accounts and empirical evidence from behavioral, eye-tracking, and neural assessments of attention to discuss our current understanding of the development of normative threat-related attention in infancy, as well as maladaptive threat-related attention patterns that may be associated with the development of anxiety. This review highlights the importance of measuring threat-related attention using multiple attention paradigms at multiple levels of analysis. In order to understand if and how threat-related attention bias in real-life, social interactive contexts can predict socioemotional development outcomes, this review proposes that future research cannot solely rely on screen-based paradigms but needs to extend the assessment of threat-related attention to naturalistic settings. Mobile eye-tracking technology provides an effective tool for capturing threat-related attention processes in vivo as children navigate fear-eliciting environments and may help us uncover more proximal bio-psycho-behavioral markers of anxiety.

Zoning out: Automatic and conscious attention biases are differentially related to dissociative and post-traumatic symptoms

Few studies of attention bias in traumatized samples directly compare automatic and conscious (e.g. supraliminal) attentional strategies. Additionally, research to-date indicates inconsistent evidence for threat-related attention bias in individuals with PTSD symptoms. This may be due to the heterogeneity in PTSD symptoms and concurrent dissociation, particularly derealization and depersonalization, since these may contribute to decreased awareness of, or slower responding to, threatening stimuli. Using an internet-based paradigm, the current study measured attention biases in a visual dot-probe task using rapid (250 ms), brief supraliminal (500 ms), and long-latency supraliminal (2000 ms) exposures. One hundred and forty-seven adult participants completed a range of trauma-related symptom measures. Results indicated a significant association between PTSD symptoms and bias toward threat in the 2000 ms exposure. Both state and trait derealization were significantly related to a bias away from threat at the 250 ms exposure, indicating a reflexive avoidance of rapidly presented threat cues. State measures of dissociation were also related to avoidance of threat in the 500 ms condition. Findings highlight the disparate effects of trauma-related symptoms on attention, and have significant clinical implications for dissociative symptoms as a target of treatment in traumatized samples.

Translating experimental paradigms into individual-differences research: Contributions, challenges, and practical recommendations

Psychological science has long been cleaved by a fundamental divide between researchers who experimentally manipulate variables and those who measure existing individual-differences. Increasingly, however, researchers are appreciating the value of integrating these approaches. Here, we used visual attention research as a case-in-point for how this gap can be bridged. Traditionally, researchers have predominately adopted experimental approaches to investigating visual attention. Increasingly, however, researchers are integrating individual-differences approaches with experimental approaches to answer novel and innovative research questions. However, individual differences research challenges some of the core assumptions and practices of experimental research. The purpose of this review, therefore, is to provide a timely summary and discussion of the key issues. While these are contextualised in the field of visual attention, the discussion of these issues has implications for psychological research more broadly. In doing so, we provide eight practical recommendations for proposed solutions and novel avenues for research moving forward.

The Innate Alarm System and Subliminal Threat Presentation in Posttraumatic Stress Disorder: Neuroimaging of the Midbrain and Cerebellum

BACKGROUND

The innate alarm system, a network of interconnected midbrain, other brainstem, and thalamic structures, serves to rapidly detect stimuli in the environment prior to the onset of conscious awareness. This system is sensitive to threatening stimuli and has evolved to process these stimuli subliminally for hastened responding. Despite the conscious unawareness, the presentation of subliminal threat stimuli generates increased activation of limbic structures, including the amygdala and insula, as well as emotionally evaluative structures, including the cerebellum and orbitofrontal cortex. Posttraumatic stress disorder (PTSD) is associated with an increased startle response and decreased extinction learning to conditioned threat. The role of the innate alarm system in the clinical presentation of PTSD, however, remains poorly understood.

METHODS

Here, we compare midbrain, brainstem, and cerebellar activation in persons with PTSD (n = 26) and matched controls (n = 20) during subliminal threat presentation. Subjects were presented with masked trauma-related and neutral stimuli below conscious threshold. Contrasts of subliminal brain activation for the presentation of neutral stimuli were subtracted from trauma-related brain activation. Group differences in activation, as well as correlations between clinical scores and PTSD activation, were examined. Imaging data were preprocessed utilizing the spatially unbiased infratentorial template toolbox within SPM12.

RESULTS

Analyses revealed increased midbrain activation in PTSD as compared to controls in the superior colliculus, periaqueductal gray, and midbrain reticular formation during subliminal threat as compared to neutral stimulus presentation. Controls showed increased activation in the right cerebellar lobule V during subliminal threat presentation as compared to PTSD. Finally, a negative correlation emerged between PTSD patient scores on the Multiscale Dissociation Inventory for the Depersonalization/Derealization subscale and activation in the right lobule V of the cerebellum during the presentation of subliminal threat as compared to neutral stimuli.

CONCLUSION

We interpret these findings as evidence of innate alarm system overactivation in PTSD and of the prominent role of the cerebellum in the undermodulation of emotion observed in PTSD.

Early adolescent adversity inflates threat estimation in females and promotes alcohol use initiation in both sexes

Childhood adversity is associated with exaggerated threat processing and earlier alcohol use initiation. Conclusive links remain elusive, as childhood adversity typically co-occurs with detrimental socioeconomic factors, and its impact is likely moderated by biological sex. To unravel the complex relationships among childhood adversity, sex, threat estimation, and alcohol use initiation, we exposed female and male Long-Evans rats to early adolescent adversity (EAA). In adulthood, >50 days following the last adverse experience, threat estimation was assessed using a novel fear discrimination procedure in which cues predict a unique probability of footshock: danger (p = 1.00), uncertainty (p = .25), and safety (p = .00). Alcohol use initiation was assessed using voluntary access to 20% ethanol, >90 days following the last adverse experience. During development, EAA slowed body weight gain in both females and males. In adulthood, EAA selectively inflated female threat estimation, exaggerating fear to uncertainty and safety, but promoted alcohol use initiation across sexes. Meaningful relationships between threat estimation and alcohol use initiation were not observed, underscoring the independent effects of EAA. Results isolate the contribution of EAA to adult threat estimation, alcohol use initiation, and reveal moderation by biological sex. (PsycINFO Database Record

Temporal dynamics in attention bias: effects of sex differences, task timing parameters, and stimulus valence

New methods of calculating indices from the dot-probe task measure temporal dynamics in attention bias or fluctuations in attention bias towards and away from emotional stimuli over time. However, it is unclear how task-specific parameters such as stimulus valence and stimulus onset asynchrony (SOA) as well as participant sex affect temporal dynamics in attention bias. To address this, male and female participants (N = 106) completed either a fearful or happy face dot-probe task with four levels of SOA (84 ms, 168 ms, 336 ms, and 672 ms). Results suggest that temporal dynamics in attention bias are (1) greatest at the longest SOA, (2) greater in females, and (3) insensitive to stimulus valence. These findings indicate that participant sex and task timing, but not stimulus valence, are related to temporal dynamics in attention bias and should be considered in future studies utilizing this approach.

Neurocognitive and Information Processing Biases in Posttraumatic Stress Disorder

PURPOSE OF REVIEW

We review recent research addressing neurocognitive and information processing abnormalities in posttraumatic stress disorder (PTSD), including studies informing direction of causality. We additionally consider neurocognition in the context of co-morbid mild traumatic brain injury (TBI) and psychosocial treatments for PTSD.

RECENT FINDINGS

Learning, memory, attention, inhibitory functions, and information processing biases frequently accompany PTSD, reflecting potential bi-directional relationships with PTSD. Although mild TBI is associated with increased risk of PTSD development and maintenance, TBI does not typically contribute significantly to sustained neurocognitive deficits in individuals with PTSD. Whereas better learning and memory is associated with mildly enhanced response to psychosocial interventions, such interventions may also improve neurocognitive performance and can be effectively provided to patients with TBI history. PTSD is associated with cognitive abnormalities in processing both emotionally relevant and emotionally neutral information and, although mild, may underlie some PTSD symptom expression.

A Latent Variable Approach to Differentiating Neural Mechanisms of Irritability and Anxiety in Youth

IMPORTANCE

Comorbidity is ubiquitous in psychiatry, but it is unclear how to differentiate neural mechanisms of co-occurring symptoms. Pediatric irritability and anxiety symptoms are prevalent and frequently co-occur. Threat orienting is pertinent to both phenotypes and is an ideal context in which to examine their unique and common neural mechanisms.

OBJECTIVES

To decompose the unique and shared variances of pediatric irritability and anxiety symptoms and to determine neural correlates of these differentiated phenotypes during threat orienting.

DESIGN, SETTING, AND PARTICIPANTS

This investigation was a cross-sectional functional magnetic resonance imaging study. The setting was a research clinic at the National Institute of Mental Health. Participants were youth aged 8 to 18 years spanning multiple diagnostic categories (141 youth with disruptive mood dysregulation disorder, anxiety disorder, and/or attention-deficit/hyperactivity disorder and 56 healthy youth). This combination provided wide variation in levels of irritability and anxiety symptoms. Data were acquired between June 30, 2012, and June 28, 2016.

MAIN OUTCOMES AND MEASURES

Participants and parents rated youth's irritability on the Affective Reactivity Index and anxiety on the Screen for Child Anxiety Related Emotional Disorders. Bifactor analysis decomposed the unique and shared variances. A functional magnetic resonance imaging dot-probe task assessed attention orienting to angry (ie, threat) vs neutral faces. Whole-brain analyses examined associations between the bifactor-derived phenotypes and both neural activity and amygdala functional connectivity.

RESULTS

Among 197 participants included in the final analysis, the mean (SD) age was 13.1 (2.7) years, and 91 (46.2%) were female. The best-fit bifactor model (Comparative Fit Index, 0.959; Root Mean Square Error of Approximation, 0.066) included unique factors of parent-reported irritability, youth-reported irritability, and anxiety, as well as a common factor of negative affectivity. When the task required attention away from threat, higher parent-reported irritability was associated with increased activity in the insula, caudate, dorsolateral and ventrolateral prefrontal cortex, and inferior parietal lobule (t189≥4.15 for all, P < .001 for all). In contrast, higher anxiety was associated with decreased amygdala connectivity to the cingulate, thalamus, and precentral gyrus (t189≤-4.19 for all, P < .001 for all). These distinctive neural correlates did not emerge using a diagnostic approach.

CONCLUSIONS AND RELEVANCE

A latent variable approach to parsing co-occurring symptom dimensions revealed a novel double dissociation. During orientation away from threat, only irritability was associated with neural activity, whereas only anxiety was associated with amygdala connectivity. Despite the challenges of symptom co-occurrence for clinical neuroscience, data-driven phenotyping may facilitate a path forward.

Stress Response Modulation Underlying the Psychobiology of Resilience

PURPOSE OF REVIEW

This review focuses on the relationship between resilience and the ability to effectively modulate the stress response. Neurobiological and behavioral responses to stress are highly variable. Exposure to a similar stressor can lead to heterogeneous outcomes-manifesting psychopathology in one individual, but having minimal effect, or even enhancing resilience, in another. We highlight aspects of stress response modulation related to early life development and epigenetics, selected neurobiological and neurochemical systems, and a number of emotional, cognitive, psychosocial, and behavioral factors important in resilience. We also briefly discuss interventions with potential to build and promote resilience.

RECENT FINDINGS

Throughout this review, we include evidence from recent preclinical and clinical studies relevant to the psychobiology of resilient stress response modulation. Effective modulation of the stress response is an essential component of resilience and is dependent on a complex interplay of neurobiological and behavioral factors.

Association between attention bias to threat and anxiety symptoms in children and adolescents

BACKGROUND

Considerable research links threat-related attention biases to anxiety symptoms in adults, whereas extant findings on threat biases in youth are limited and mixed. Inconsistent findings may arise due to substantial methodological variability and limited sample sizes, emphasizing the need for systematic research on large samples. The aim of this report is to examine the association between threat bias and pediatric anxiety symptoms using standardized measures in a large, international, multi-site youth sample.

METHODS

A total of 1,291 children and adolescents from seven research sites worldwide completed standardized attention bias assessment task (dot-probe task) and child anxiety symptoms measure (Screen for Child Anxiety Related Emotional Disorders). Using a dimensional approach to symptomatology, we conducted regression analyses predicting overall, and disorder-specific, anxiety symptoms severity, based on threat bias scores.

RESULTS

Threat bias correlated positively with overall anxiety symptoms severity (ß = 0.078, P = .004). Furthermore, threat bias was positively associated specifically with social anxiety (ß = 0.072, P = .008) and school phobia (ß = 0.076, P = .006) symptoms severity, but not with panic, generalized anxiety, or separation anxiety symptoms. These associations were not moderated by age or gender.

CONCLUSIONS

These findings indicate associations between threat bias and pediatric anxiety symptoms, and suggest that vigilance to external threats manifests more prominently in symptoms of social anxiety and school phobia, regardless of age and gender. These findings point to the role of attention bias to threat in anxiety, with implications for translational clinical research. The significance of applying standardized methods in multi-site collaborations for overcoming challenges inherent to clinical research is discussed.

Attention training modulates resting-state neurophysiological abnormalities in posttraumatic stress disorder

Recent research indicates the relative benefits of computerized attention control treatment (ACT) and attention bias modification treatment (ABMT) for posttraumatic stress disorder (PTSD); however, neural changes underlying these therapeutic effects remain unknown. This study examines how these two types of attention training modulate neurological dysfunction in veterans with PTSD. A community sample of 46 combat veterans with PTSD participated in a randomized double-blinded clinical trial of ACT versus ABMT and 32 of those veterans also agreed to undergo resting-state magnetoencephalography (MEG) recordings. Twenty-four veterans completed psychological and MEG assessments at pre- and post-training to evaluate treatment effects. MEG data were imaged using an advanced Bayesian reconstruction method and examined using statistical parametric mapping. In this report, we focus on the neural correlates and the differential treatment effects observed using MEG; the results of the full clinical trial have been described elsewhere. Our results indicated that ACT modulated occipital and ABMT modulated medial temporal activity more strongly than the comparative treatment. PTSD symptoms decreased significantly from pre- to post-test. These initial neurophysiological outcome data suggest that ACT modulates visual pathways, while ABMT modulates threat-processing regions, but that both are associated with normalizing aberrant neural activity in veterans with PTSD.

Associability-modulated loss learning is increased in posttraumatic stress disorder

Disproportionate reactions to unexpected stimuli in the environment are a cardinal symptom of posttraumatic stress disorder (PTSD). Here, we test whether these heightened responses are associated with disruptions in distinct components of reinforcement learning. Specifically, using functional neuroimaging, a loss-learning task, and a computational model-based approach, we assessed the mechanistic hypothesis that overreactions to stimuli in PTSD arise from anomalous gating of attention during learning (i.e., associability). Behavioral choices of combat-deployed veterans with and without PTSD were fit to a reinforcement learning model, generating trial-by-trial prediction errors (signaling unexpected outcomes) and associability values (signaling attention allocation to the unexpected outcomes). Neural substrates of associability value and behavioral parameter estimates of associability updating, but not prediction error, increased with PTSD during loss learning. Moreover, the interaction of PTSD severity with neural markers of associability value predicted behavioral choices. These results indicate that increased attention-based learning may underlie aspects of PTSD and suggest potential neuromechanistic treatment targets.

Enhanced Attentional Bias Variability in Post-Traumatic Stress Disorder and its Relationship to More General Impairments in Cognitive Control

Hypervigilance towards threat is one of the defining features of post-traumatic stress disorder (PTSD). This symptom predicts that individuals with PTSD will be biased to attend to potential dangers in the environment. However, cognitive tasks designed to assess visual-spatial attentional biases have shown mixed results. A newer proposal suggests that attentional bias is not a static phenomenon, but rather is characterized by fluctuations towards and away from threat. Here, we tested 28 combat Veterans with PTSD and 28 control Veterans on a dot probe task with negative-neutral word pairs. Combat-related words and generically negative words were presented in separate blocks. Replicating previous results, neither group showed a bias to attend towards or away from threat, but PTSD patients showed greater attentional bias variability (ABV), which correlated with symptom severity. However, the cognitive processes indexed by ABV are unclear. The present results indicated that ABV was strongly correlated with standard deviation at the reaction time (RT) level and with excessively long RTs (ex-Gaussian tau) related to cognitive failures. These findings suggest an overall increase in response variability unrelated to threat-related biases in spatial attention, and support a disruption in more general cognitive control processes in PTSD.

Temporal dynamics of anxiety-related attentional bias: is affective context a missing piece of the puzzle?

Previous research has demonstrated that anxious individuals attend to negative emotional information at the expense of other information. This is commonly referred to as attentional bias. The field has historically conceived of this process as relatively static; however, research by [Zvielli, A., Bernstein, A., & Koster, E. H. W. (2014). Dynamics of attentional bias to threat in anxious adults: Bias towards and/or away? PLoS ONE, 9(8), e104025; Zvielli, A., Bernstein, A., & Koster, E. H. W. (2015). Temporal dynamics of attentional bias. Clinical Psychological Science, 3(5), 772-788.], and others, challenges this assumption by demonstrating considerable temporal variability in attentional bias amongst anxious individuals. Still, the mechanisms driving these temporal dynamics are less well known. Using a modified dot-probe task, the present study examined the impact of two relevant contextual variables- affective valence and trial repetition. Affective context was instantiated by the presentation of negative versus neutral pictures before each trial, while repetition context was achieved via the presentation of the valenced pictures in either a blocked- or mixed-trial design. Results indicate that individuals with higher trait-anxiety levels were significantly more influenced by blocked presentations of negative affective information, leading to greater temporal fluctuations in attentional bias. Furthermore, our findings provide additional evidence that attentional bias is best conceptualised as dynamic and variable, and that an individual's affective experience is one factor that regulates attentional bias dynamics. Implications relating to theoretical and methodological factors are discussed.

Fronto-Limbic Alterations in Negatively Biased Attention in Young Adults with Subthreshold Depression

Attentional bias toward negative stimuli has been observed in major depression disorders (MDDs). Imaging studies suggest the engagement of fronto-limbic regions like amygdala, anterior cingulate cortex (ACC), and lateral prefrontal cortex, is related to negatively biased attention. However, neural correlates of attentional bias for negative stimuli in individuals with subthreshold depression (SubD), that is individuals who have clinically relevant depressive symptoms but do not fulfill the criteria for MDD, remain unclear. Here, we used functional neuroimaging and the dot-probe task to elucidate the neural substrates of negatively biased attention among individuals with SubD. Behavioral results found that individuals with SubD allocated more attention toward negative stimuli relative to neutral stimuli, which were not observed among non-depressed controls (NCs). Imaging results found greater amygdala and rostral ACC activity in attentional bias toward negative stimuli among participants with SubD compared to NCs; Additionally, participants with SubD showed reduced engagement of bilateral inferior frontal gyrus compared with NCs in the attentional processing of negative stimuli. Together, these results suggest that alteration of fronto-limbic systems relative to controls, known to be related to negative detection and attentional control, is associated with negatively biased attention in individuals with SubD.

Content specificity of attentional bias to threat in post-traumatic stress disorder

BACKGROUND

Attentional bias to affective information and reduced cognitive control may maintain the symptoms of post-traumatic stress disorder (PTSD) and impair cognitive functioning. However, the role of content specificity of affective stimuli (e.g., trauma-related, emotional trauma-unrelated) in the observed attentional bias and cognitive control is less clear, as this has not been tested simultaneously before. Therefore, we examined the content specificity of attentional bias to threat in PTSD.

METHODS

PTSD participants (survivors of a multistory factory collapse, n=30) and matched controls (n=30) performed an Eriksen Flanker task. They identified the direction of a centrally presented target arrow, which was flanked by several task-irrelevant distractor arrows pointed to the same (congruent) or opposite direction (incongruent). Additionally, participants were presented with a picture of a face (neutral, emotional) or building (neutral=normal, emotional=collapsed multistory factory) as a task-irrelevant background image.

RESULTS

We found that PTSD participants produced overall larger conflict effects and longer reaction times (RT) to emotional than to neutral stimuli relative to their healthy counterparts. Moreover, PTSD, but not healthy participants showed a stimulus specific dissociation in processing emotional stimuli. Emotional faces elicited longer RTs compared to neutral faces, while emotional buildings elicited faster responses, compared to neutral buildings.

CONCLUSIONS

PTSD patients show a content-sensitive attentional bias to emotional information and impaired cognitive control.

Facial expression movement enhances the measurement of temporal dynamics of attentional bias in the dot-probe task

The facial dot-probe task is one of the most common experimental paradigms used to assess attentional bias toward emotional information. In recent years, however, the psychometric properties of this paradigm have been questioned. In the present study, attentional bias to emotional face stimuli was measured with dynamic and static images of realistic human faces in 97 college students (63 women) who underwent either a positive or a negative mood-induction prior to the experiment. We controlled the bottom-up salience of the stimuli in order to dissociate the top-down orienting of attention from the effects of the bottom-up physical properties of the stimuli. A Bayesian analysis of our results indicates that 1) the traditional global attentional bias index shows a low reliability, 2) reliability increases dramatically when biased attention is analyzed by extracting a series of bias estimations from trial-to-trial (Zvielli, Bernstein, & Koster, 2015), 3) dynamic expression of emotions strengthens biased attention to emotional information, and 4) mood-congruency facilitates the measurement of biased attention to emotional stimuli. These results highlight the importance of using ecologically valid stimuli in attentional bias research, together with the importance of estimating biased attention at the trial level.

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.

Acute stress disorder

Acute stress disorder (ASD) was introduced in DSM-IV to describe posttraumatic stress disorder (PTSD) symptoms that (a) occur in the initial month after trauma and (b) predict subsequent PTSD. Longitudinal studies have shown that most people who develop PTSD do not initially meet ASD criteria, which led to the decision in DSM-5 to limit the ASD diagnosis to describing acute stress reactions without any predictive function. Controlled trials have shown that trauma-focused cognitive behavior therapy is the treatment of choice for ASD, and is superior to pharmacological interventions. Recent longitudinal studies have challenged previous conceptualizations of the course of posttraumatic stress, and highlighted that people follow different trajectories of adaptation that are influenced by events that occur after the acute posttraumatic period.

Threat Monitoring and Attention-Bias Modification in Anxiety and Stress-Related Disorders

Extensive research has demonstrated the effects of threat-related attentional bias on anxiety and stress-related disorders. This review summarizes recent findings from clinical affective neuroscience. It takes a multilevel analysis approach by presenting behavioral and neural findings from studies conducted in laboratories, clinical settings, and real-life situations. Building on recent findings, we propose a new working model linking individual tendencies to attend or avoid threats with the level of danger in a given context. Namely, adaptive or pathological response is determined by threat-monitoring flexibility and plasticity in an ever-changing environment. The review culminates by describing the potential therapeutic value of attention-bias modification in the treatment of anxiety and stress-related disorders.

Capturing Dynamics of Biased Attention: Are New Attention Variability Measures the Way Forward?

Background

New indices, calculated on data from the widely used Dot Probe Task, were recently proposed to capture variability in biased attention allocation. We observed that it remains unclear which data pattern is meant to be indicative of dynamic bias and thus to be captured by these indices. Moreover, we hypothesized that the new indices are sensitive to SD differences at the response time (RT) level in the absence of bias.

Method

Randomly generated datasets were analyzed to assess properties of the Attention Bias Variability (ABV) and Trial Level Bias Score (TL-BS) indices. Sensitivity to creating differences in 1) RT standard deviation, 2) mean RT, and 3) bias magnitude were assessed. In addition, two possible definitions of dynamic attention bias were explored by creating differences in 4) frequency of bias switching, and 5) bias magnitude in the presence of constant switching.

Results

ABV and TL-BS indices were found highly sensitive to increasing SD at the response time level, insensitive to increasing bias, linearly sensitive to increasing bias magnitude in the presence of bias switches, and non-linearly sensitive to increasing the frequency of bias switches. The ABV index was also found responsive to increasing mean response times in the absence of bias.

Conclusion

Recently proposed DPT derived variability indices cannot uncouple measurement error from bias variability. Significant group differences may be observed even if there is no bias present in any individual dataset. This renders the new indices in their current form unfit for empirical purposes. Our discussion focuses on fostering debate and ideas for new research to validate the potentially very important notion of biased attention being dynamic.

Attention bias modification for youth with social anxiety disorder

BACKGROUND

Attention bias modification treatment (ABMT) targets threat-related attention biases in anxiety disorders. Most clinical trials of ABMT have focused on adults or small samples of youth. The current randomized controlled trial (RCT) examines ABMT efficacy in youth with social anxiety disorder (SAD) and tests possible moderators of treatment outcomes.

METHOD

Sixty-seven youth with SAD were randomly assigned to ABMT or attention control training (ACT) conditions. Anxiety severity was measured at baseline, posttreatment, and 3-month follow-up. ClinicalTrials.gov name and identifier: Attention bias modification treatment for children with social anxiety, NCT01397032; http://www.clinicaltrials.gov.

RESULTS

Both ABMT and ACT induced significant reductions in clinician and self-rated social anxiety (ps < .001). An additional reduction was observed at the 3-month follow-up in clinician-rated anxiety symptoms (p = .03). Moderation effects were nonsignificant for the clinician-rated anxiety outcome, but age moderated self-reported anxiety. Older but not younger children, showed significant reduction in anxiety following ABMT relative to ACT (p < .001). Individual differences in attention control also moderated ABMT's effect on self-reported anxiety (p = .05). Children rated by their parents as lower on attention control benefited more from ABMT than those rated higher on attention control. Baseline attention bias did not moderate anxiety (p = .17).

CONCLUSIONS

Despite significant reductions in social anxiety, no specific evidence for ABMT was found relative to a control condition. Age and attention control moderated ABMT effects on self-reported SAD symptoms, with clinical effects for older relative to younger children and for those with lower attention control. These results highlight the need to consider developmental influences in the implementation of ABMT protocols.

A developmental neuroscience perspective on affect-biased attention

There is growing interest regarding the impact of affect-biased attention on psychopathology. However, most of the research to date lacks a developmental approach. In the present review, we examine the role affect-biased attention plays in shaping socioemotional trajectories within a developmental neuroscience framework. We propose that affect-biased attention, particularly if stable and entrenched, acts as a developmental tether that helps sustain early socioemotional and behavioral profiles over time, placing some individuals on maladaptive developmental trajectories. Although most of the evidence is found in the anxiety literature, we suggest that these relations may operate across multiple domains of interest, including positive affect, externalizing behaviors, drug use, and eating behaviors. We also review the general mechanisms and neural correlates of affect-biased attention, as well as the current evidence for the co-development of attention and affect. Based on the reviewed literature, we propose a model that may help us better understand the nuances of affect-biased attention across development. The model may serve as a strong foundation for ongoing attempts to identify neurocognitive mechanisms and intervene with individuals at risk. Finally, we discuss open issues for future research that may help bridge existing gaps in the literature.

Attention and interpretation processes and trait anger experience, expression, and control

This study explored attention and interpretation biases in processing facial expressions as correlates of theoretically distinct self-reported anger experience, expression, and control. Non-selected undergraduate students (N = 101) completed cognitive tasks measuring attention bias, interpretation bias, and Spielberger's State-Trait Anger Expression Inventory (STAXI-2). Attention bias toward angry faces was associated with higher trait anger and anger expression and with lower anger control-in and anger control-out. The propensity to quickly interpret ambiguous faces as angry was associated with greater anger expression and its subcomponent of anger expression-out and with lower anger control-out. Interactions between attention and interpretation biases did not contribute to the prediction of any anger component suggesting that attention and interpretation biases may function as distinct mechanisms. Theoretical and possible clinical implications are discussed.

Selective prevention of combat-related post-traumatic stress disorder using attention bias modification training: a randomized controlled trial

BACKGROUND

Efficacy of pre-trauma prevention for post-traumatic stress disorder (PTSD) has not yet been established in a randomized controlled trial. Attention bias modification training (ABMT), a computerized intervention, is thought to mitigate stress-related symptoms by targeting disruptions in threat monitoring. We examined the efficacy of ABMT delivered before combat in mitigating risk for PTSD following combat.

METHOD

We conducted a double-blind, four-arm randomized controlled trial of 719 infantry soldiers to compare the efficacy of eight sessions of ABMT (n = 179), four sessions of ABMT (n = 184), four sessions of attention control training (ACT; n = 180), or no-training control (n = 176). Outcome symptoms were measured at baseline, 6-month follow-up, 10 days following combat exposure, and 4 months following combat. Primary outcome was PTSD prevalence 4 months post-combat determined in a clinical interview using the Clinician-Administered PTSD Scale. Secondary outcomes were self-reported PTSD and depression symptoms, collected at all four assessments.

RESULTS

PTSD prevalence 4 months post-combat was 7.8% in the no-training control group, 6.7% with eight-session ABMT, 2.6% with four-session ABMT, and 5% with ACT. Four sessions of ABMT reduced risk for PTSD relative to the no-training condition (odds ratio 3.13, 95% confidence interval 1.01-9.22, p < 0.05, number needed to treat = 19.2). No other between-group differences were found. The results were consistent across a variety of analytic techniques and data imputation approaches.

CONCLUSIONS

Four sessions of ABMT, delivered prior to combat deployment, mitigated PTSD risk following combat exposure. Given its low cost and high scalability potential, and observed number needed to treat, research into larger-scale applications is warranted. The ClinicalTrials.gov identifier is NCT01723215.

Attention bias in adults with anorexia nervosa, obsessive-compulsive disorder, and social anxiety disorder

BACKGROUND

Attention bias to threat (selective attention toward threatening stimuli) has been frequently found in anxiety disorder samples, but its distribution both within and beyond this category is unclear. Attention bias has been studied extensively in social anxiety disorder (SAD) but relatively little in obsessive compulsive disorder (OCD), historically considered an anxiety disorder, or anorexia nervosa (AN), which is often characterized by interpersonal as well as body image/eating fears.

METHODS

Medication-free adults with SAD (n = 43), OCD (n = 50), or AN (n = 30), and healthy control volunteers (HC, n = 74) were evaluated for attention bias with an established dot probe task presenting images of angry and neutral faces. Additional outcomes included attention bias variability (ABV), which summarizes fluctuation in attention between vigilance and avoidance, and has been reported to have superior reliability. We hypothesized that attention bias would be elevated in SAD and associated with SAD severity.

RESULTS

Attention bias in each disorder did not differ from HC, but within the SAD group attention bias correlated significantly with severity of social avoidance. ABV was significantly lower in OCD versus HC, and it correlated positively with severity of OCD symptoms within the OCD group.

CONCLUSIONS

Findings do not support differences from HC in attention bias to threat faces for SAD, OCD, or AN. Within the SAD sample, the association of attention bias with severity of social avoidance is consistent with evidence that attention bias moderates development of social withdrawal. The association of ABV with OCD diagnosis and severity is novel and deserves further study.

Behavioral and neural stability of attention bias to threat in healthy adolescents

Considerable translational research on anxiety examines attention bias to threat and the efficacy of attention training in reducing symptoms. Imaging research on the stability of brain functions engaged by attention bias tasks could inform such research. Perturbed fronto-amygdala function consistently arises in attention bias research on adolescent anxiety. The current report examines the stability of the activation and functional connectivity of these regions on the dot-probe task. Functional magnetic resonance imaging (fMRI) activation and connectivity data were acquired with the dot-probe task in 39 healthy youth (f=18, Mean Age=13.71years, SD=2.31) at two time points, separated by approximately nine weeks. Intraclass-correlations demonstrate good reliability in both neural activation for the ventrolateral PFC and task-specific connectivity for fronto-amygdala circuitry. Behavioral measures showed generally poor test-retest reliability. These findings suggest potential avenues for future brain imaging work by highlighting brain circuitry manifesting stable functioning on the dot-probe attention bias task.

Understanding resilience: New approaches for preventing and treating PTSD

All individuals experience stressful life events, and up to 84% of the general population will experience at least one potentially traumatic event. In some cases, acute or chronic stressors lead to the development of posttraumatic stress disorder (PTSD) or other psychopathology; however, the majority of people are resilient to such effects. Resilience is the ability to adapt successfully in the face of stress and adversity. A wealth of research has begun to identify the genetic, epigenetic, neural, and environmental underpinnings of resilience, and has indicated that resilience is mediated by adaptive changes encompassing several environmental factors, neural circuits, numerous neurotransmitters, and molecular pathways. The first part of this review focuses on recent findings regarding the genetic, epigenetic, developmental, psychosocial, and neurochemical factors as well as neural circuits and molecular pathways that underlie the development of resilience. Emerging and exciting areas of research and novel methodological approaches, including genome-wide gene expression studies, immune, endocannabinoid, oxytocin, and glutamatergic systems, are explored to help delineate innovative mechanisms that may contribute to resilience. The second part reviews several interventions and preventative approaches designed to enhance resilience in both developmental and adult populations. Specifically, the review will delineate approaches aimed to bolster resilience in individuals with PTSD. Furthermore, we discuss novel pharmacologic approaches, including the N-methyl-d-aspartate (NMDA) receptor ketamine and neuropeptide Y (NPY), as exciting new prospects for not only the treatment of PTSD but as new targets to enhance resilience. Our growing understanding of resilience and interventions will hopefully lead to the development of new strategies for not just treating PTSD but also screening and early identification of at-risk youth and adults. Taken together, efforts aimed at dissemination and implementation of novel interventions to enhance resilience will have to keep pace with the growth of new preventive and treatment strategies.

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.

History of childhood maltreatment augments dorsolateral prefrontal processing of emotional valence in PTSD

Posttraumatic stress disorder (PTSD) is characterized by conflicting findings of both increased and decreased amygdala and prefrontal reactivity to threat or trauma stimuli. Childhood maltreatment (CM), a potent risk factor for PTSD, exerts long-lasting influences on threat processing and prefrontal-amygdala function. This suggests that CM history may influence PTSD neural phenotypes related to threat processing. Here, we adapt a well-characterized emotional conflict paradigm to investigate CM effects on both emotional conflict and emotional valence processing within PTSD stratified by task relevance. Forty-two individuals with PTSD (22 reporting extensive CM history (PTSD-CM)) and 20 trauma-exposed healthy controls (TEHCs) underwent functional magnetic resonance imaging while identifying affect of emotional faces (fear and happy) overlaid with a goal-irrelevant emotional distractor word ("FEAR" or "HAPPY"). We examined effects of CM on conflict, conflict adaptation, valence-related activation (fear vs. happy) for goal-relevant (face) and goal-irrelevant stimuli (word), and valence effects in interaction with goal-relevancy (face vs. word). Though no activation differences between groups were observed for conflict contrasts nor for valence effects in the amygdala, CM status interacted with valence processing differences as a function of goal relevance in the left dorsolateral prefrontal cortex (dlPFC). Here, PTSD-CM displayed greater activation relative to PTSD to negative valence when stimuli were goal-irrelevant. CM history also moderated relationships between activation abnormalities and PTSD re-experiencing symptoms. These findings provide initial evidence that CM history augments dorsolateral prefrontal bias to implicitly processed stimulus valence in PTSD.

The neurobiology of dispositional negativity and attentional biases to threat: Implications for understanding anxiety disorders in adults and youth

When extreme, anxiety can become debilitating. Anxiety disorders, which often first emerge early in development, are common and challenging to treat, yet the neurocognitive mechanisms that confer increased risk have only recently begun to come into focus. Here we review recent work highlighting the importance of neural circuits centered on the amygdala. We begin by describing dispositional negativity, a core dimension of childhood temperament and adult personality and an important risk factor for the development of anxiety disorders and other kinds of stress-sensitive psychopathology. Converging lines of epidemiological, neurophysiological, and mechanistic evidence indicate that the amygdala supports stable individual differences in dispositional negativity across the lifespan and contributes to the etiology of anxiety disorders in adults and youth. Hyper-vigilance and attentional biases to threat are prominent features of the anxious phenotype and there is growing evidence that they contribute to the development of psychopathology. Anatomical studies show that the amygdala is a hub, poised to govern attention to threat via projections to sensory cortex and ascending neuromodulatory systems. Imaging and lesion studies demonstrate that the amygdala plays a key role in selecting and prioritizing the processing of threat-related cues. Collectively, these observations provide a neurobiologically-grounded framework for understanding the development and maintenance of anxiety disorders in adults and youth and set the stage for developing improved intervention strategies.