Converging Multi-modal Evidence for Implicit Threat-Related Bias in Pediatric Anxiety Disorders

Using mobile eye-tracking to evaluate gaze behavior during a speech in pediatric anxiety disorders

BACKGROUND

Altered gaze in social settings is a hallmark of social anxiety; however, little research directly examines gaze in anxiety-provoking contexts among youth with anxiety disorders, limiting mechanistic insight into pediatric anxiety. The present study leveraged mobile eye-tracking technology to examine gaze behavior during a naturalistic stressor in a clinical developmental sample.

METHODS

Sixty-one youth (ages 8-17 years; 28 with anxiety disorders, 33 non-anxious controls) completed a naturalistic social stress task (public speaking in front of a videotaped classroom audience) while wearing eye-tracking glasses. Gaze behavior and state anxiety were quantified in each group during two task conditions: while giving a speech and while passively viewing the audience.

RESULTS

Anxiety-related differences emerged in state anxiety and gaze behavior. First, a significant interaction between diagnostic group and task condition on state anxiety indicated that while anxiety increased among non-anxious controls following the speech, youth with anxiety disorders reported persistently elevated anxiety across all assessments. Second, a significant interaction emerged between social anxiety symptom severity and task condition on gaze time on the audience. While youth overall showed low dwell time on the audience during speech delivery, individuals with greater social anxiety showed longer gaze on the audience during the passive viewing condition. This pattern was specific to dimensional analyses of social anxiety symptom severity.

LIMITATIONS

The current study was not sufficiently powered to examine age-related differences.

CONCLUSIONS

These findings highlight anxiety-related differences in gaze behavior in youth, providing new mechanistic insight into pediatric anxiety using mobile eye-tracking.

Eye-tracking measurement of attention bias to social threat among youth: A replication and extension study

Attentional bias to social threat cues has been linked to heightened anxiety and irritability in youth. Yet, inconsistent methodology has limited replication and led to mixed findings. The current study aims to 1) replicate and extend two previous pediatric studies demonstrating a relationship between negative affectivity and attentional bias to social threat and 2) examine the test-retest reliability of an eye-tracking paradigm among a subsample of youth. Attention allocation to negative versus non-negative emotional faces was measured using a free-viewing eye-tracking task among youth (N=185 total, 60% female, M age=13.10 years, SD age=2.77) with three face-pair conditions: happy-angry, neutral-disgust, sad-happy. Replicating procedures of two previous studies, linear mixed-effects models compared attention bias between children with anxiety disorders and healthy controls. Bifactor analysis was used to parse shared versus unique facets of general negative affectivity (i.e., anxiety, irritability), which were then examined in relation to attention bias. Test-retest reliability of the bias-index was estimated among a subsample of youth (N=36). No significant differences in attention allocation or bias emerged between anxiety and healthy control groups. While general negative affectivity across the sample was not associated with attention bias, there was a positive relationship for anxiety and irritability on duration of attention allocation toward negative faces. Test-retest reliability for attention bias was moderate (r=0.50, p<.01). While anxiety-related findings from the two previous studies were not replicated, the relationship between attention bias and facets of negative affect suggests a potential target for treatment. Evidence for test-retest reliability encourages future use of the eye-tracking task for researchers.

The Organization of Anxiety Symptoms Along the Threat Imminence Continuum

Pathological anxiety is highly prevalent, impairing, and often chronic. Yet, despite considerable research, mechanistic understanding of anxiety and its translation to clinical practice remain limited. Here, we first highlight two foundational complications that contribute to this gap: a reliance on a phenomenology-driven definition of pathological anxiety in neurobiological mechanistic research, and a limited understanding of the chronicity of anxiety symptom expression. We then posit that anxiety symptoms may reflect aberrant expression of otherwise normative defensive responses. Accordingly, we propose that threat imminence, an organizing dimension for normative defensive responses observed across species, may be applied to organize and understand anxiety symptoms along a temporal dimension of expression. Empirical evidence linking distinct anxiety symptoms and the aberrant expression of imminence-dependent defensive responses is reviewed, alongside the neural mechanisms which may underpin these cognitive, physiological, and behavioral responses. Drawing from extensive translational and clinical research, we suggest that understanding anxiety symptoms through this neurobiologically-informed framework may begin to overcome the conceptual complications hindering advancement in mechanistic research and clinical interventions for pathological anxiety.

Responding to threat: Associations between neural reactivity to and behavioral avoidance of threat in pediatric anxiety

BACKGROUND

Despite broad recognition of the central role of avoidance in anxiety, a lack of specificity in its operationalization has hindered progress in understanding this clinically significant construct. The current study uses a multimodal approach to investigate how specific measures of avoidance relate to neural reactivity to threat in youth with anxiety disorders.

METHODS

Children with anxiety disorders (ages 6-12 years; n = 65 for primary analyses) completed laboratory task- and clinician-based measures of avoidance, as well as a functional magnetic resonance imaging task probing neural reactivity to threat. Primary analyses examined the ventral anterior insula (vAI), amygdala, and ventromedial prefrontal cortex (vmPFC).

RESULTS

Significant but distinct patterns of association with task- versus clinician-based measures of avoidance emerged. Clinician-rated avoidance was negatively associated with right and left vAI reactivity to threat, whereas laboratory-based avoidance was positively associated with right vAI reactivity to threat. Moreover, left vAI-right amygdala and bilateral vmPFC-right amygdala functional connectivity were negatively associated with clinician-rated avoidance but not laboratory-based avoidance.

LIMITATIONS

These results should be considered in the context of the restricted range of our treatment-seeking sample, which limits the ability to draw conclusions about these associations across children with a broader range of symptomatology. In addition, the limited racial and ethnic diversity of our sample may limit the generalizability of findings.

CONCLUSION

These findings mark an important step towards bridging neural findings and behavioral patterns using a multimodal approach. Advancing understanding of behavioral avoidance in pediatric anxiety may guide future treatment optimization by identifying individual-specific targets for treatment.

Pre-scan state anxiety is associated with greater right amygdala-hippocampal response to fearful versus happy faces among trait-anxious Latina girls

BACKGROUND

Unfamiliarity with academic research may contribute to higher levels of anticipatory state anxiety about affective neuroimaging tasks. Children with high trait anxiety display differences in brain response to fearful facial affect compared to non-anxious youth, but little is known about the influence of state anxiety on this association. Because reduced engagement in scientific research and greater mistrust among minoritized groups may lead to systematic differences in pre-scan state anxiety, it is crucial to understand the neural correlates of state anxiety during emotion processing so as to disambiguate sources of individual differences.

METHODS

The present study probed the interactive effects of pre-scan state anxiety, trait anxiety, and emotional valence (fearful vs. happy faces) on neural activation during implicit emotion processing in a community sample of 46 preadolescent Latina girls (8-13 years).

RESULTS

Among girls with mean and high levels of trait anxiety, pre-scan state anxiety was associated with greater right amygdala-hippocampal and left inferior parietal lobe response to fearful faces relative to happy faces.

CONCLUSIONS

Anticipatory state anxiety in the scanning context may cause children with moderate and high trait anxiety to be hypervigilant to threats, further compounding the effects of trait anxiety. Neuroimaging researchers should control for state anxiety so that systematic differences in brain activation resulting from MRI apprehension are not misleadingly attributed to demographic or environmental characteristics.

Attentional biases in human anxiety

Across clinical and subclinical samples, anxiety has been associated with increased attentional capture by cues signaling danger. Various cognitive models attribute the onset and maintenance of anxiety symptoms to maladaptive selective information processing. In this brief review, we 1) describe the evidence for the relations between anxiety and attention bias toward threat, 2) discuss the neurobiology of anxiety-related differences in threat bias, 3) summarize work investigating the developmental origins of attention bias toward threat, and 4) examine efforts to translate threat bias research into clinical intervention. Future directions in each area are discussed, including the use of novel analytic approaches improving characterization of threat-processing-related brain networks, clarifying the role of cognitive control in the development of attention bias toward threat, and the need for larger, well-controlled randomized clinical trials examining moderators and mediators of treatment response. Ultimately, this work has important implications for understanding the etiology of and for intervening on anxiety difficulties among children and adults.

Family accommodation in pediatric anxiety: Relations with avoidance and self-efficacy

Pediatric anxiety disorders are common, impairing, and chronic when not effectively treated. A growing body of research implicates family accommodation in the maintenance of pediatric anxiety. The present study aimed to quantify previously untested relations among family accommodation and two theoretically linked constructs: avoidance and self-efficacy. Eighty youths between ages 8 and 17 (53 with anxiety disorders, 27 non-anxious controls) completed measures of family accommodation and self-efficacy. In addition, avoidance was assessed using two distinct measures of avoidance: a clinician rating of real-world behaviors and a laboratory task-based index. As predicted, youths with anxiety disorders reported greater family accommodation than non-anxious controls. Across the sample, greater family accommodation was associated with greater avoidance, as measured using both clinician rating and the laboratory task, as well as with lower self-efficacy. In an exploratory mediation model, self-efficacy partially mediated the relation between family accommodation and clinician-rated avoidance; however, it did not mediate the relation between family accommodation and task-based avoidance. Considering the robust association between family accommodation and anxiety in youths, this addition to our understanding of related cognitive and behavioral factors provides important preliminary insight, which can guide future research on potential targets for early identification and intervention for pediatric anxiety.

Does irritability predict attention biases toward threat among clinically anxious youth?

Aberrant threat processing is a known cognitive characteristic of anxiety disorders and irritability. Youth with more severe symptomatology show greater allocation of attention towards threat relative to neutral stimuli. Although irritability contributes to poorer outcomes among anxious youths, irritability has not been considered as a contributing factor to threat processing in anxiety disorders. Thus, the current study examined the role of irritability in predicting attention biases for threat among clinically anxious youth. Our study included 84 clinically anxious youth (M = 9.31 years old, SD = 2.44) who completed a dot-probe task to determine attention biases. Anxiety disorders were assessed using semi-structured diagnostic interviews. Well validated measures were used to assess the severity of anxiety and irritability symptoms via child- and parent-report, respectively. Findings indicated that more severe irritability predicted greater attention biases toward threat among clinically anxious youth, covarying for age, anxiety severity, and the number of comorbid diagnoses. At a trend-level, anxiety severity also predicted attention bias for threat. Among clinically anxious youth, irritability severity was the strongest predictor of attention bias toward threat. Findings point to the salience of irritability, and to some extent anxiety severity, in relation to threat processing among youth with clinical anxiety disorders.

The prefrontal cortex, pathological anxiety, and anxiety disorders

Anxiety is experienced in response to threats that are distal or uncertain, involving changes in one's subjective state, autonomic responses, and behavior. Defensive and physiologic responses to threats that involve the amygdala and brainstem are conserved across species. While anxiety responses typically serve an adaptive purpose, when excessive, unregulated, and generalized, they can become maladaptive, leading to distress and avoidance of potentially threatening situations. In primates, anxiety can be regulated by the prefrontal cortex (PFC), which has expanded in evolution. This prefrontal expansion is thought to underlie primates' increased capacity to engage high-level regulatory strategies aimed at coping with and modifying the experience of anxiety. The specialized primate lateral, medial, and orbital PFC sectors are connected with association and limbic cortices, the latter of which are connected with the amygdala and brainstem autonomic structures that underlie emotional and physiological arousal. PFC pathways that interface with distinct inhibitory systems within the cortex, the amygdala, or the thalamus can regulate responses by modulating neuronal output. Within the PFC, pathways connecting cortical regions are poised to reduce noise and enhance signals for cognitive operations that regulate anxiety processing and autonomic drive. Specialized PFC pathways to the inhibitory thalamic reticular nucleus suggest a mechanism to allow passage of relevant signals from thalamus to cortex, and in the amygdala to modulate the output to autonomic structures. Disruption of specific nodes within the PFC that interface with inhibitory systems can affect the negative bias, failure to regulate autonomic arousal, and avoidance that characterize anxiety disorders.

Increased attention allocation to socially threatening faces in social anxiety disorder: A replication study

BACKGROUND

Threat-related attention bias has been implicated in the etiology and maintenance of social anxiety disorder (SAD), with attentional research increasingly using eye-tracking methodology to overcome the poor psychometric properties of response-time-based tasks and measures. Yet, extant eye-tracking research in social anxiety has mostly failed to report on psychometrics and attempts to replicate past results are rare. Therefore, we attempted to replicate a previously published eye-tracking study of gaze patterns in socially anxious and nonanxious participants as they viewed social threatening and neutral faces, while also exploring the psychometric properties of the attentional measures used.

METHODS

Gaze was monitored as participants freely viewed 60 different matrices comprised of eight socially-threatening and eight neutral faces, presented for 6000 ms each. Gaze patterns directed at threat and neutral areas of interest (AOIs) were compared by group. Internal consistency and test-retest reliability were also evaluated.

RESULTS

Relative to healthy controls, socially anxious patients dwelled significantly longer on threat faces, replicating prior findings with the same task. Internal consistency of total dwell time on threat and neutral AOIs was high, and two-week test-retest reliability was acceptable.

LIMITATIONS

Test-retest reliability was only examined for the control group, which had a small sample size.

CONCLUSION

Increased dwell time on socially threatening stimuli is a reliable, stable, and generalizable measure of attentional bias in adults with social anxiety.

Attention bias to negative versus non-negative faces is related to negative affectivity in a transdiagnostic youth sample

This study identified a shared pathophysiological mechanism of pediatric anxiety and irritability. Clinically, anxiety and irritability are common, co-occurring problems, both characterized by high-arousal negative affective states. Behaviorally, anxiety and irritability are associated with aberrant threat processing. To build on these findings, we examined eye-tracking measures of attention bias in relation to the unique and shared features of anxiety and irritability in a transdiagnostic sample of youth (n = 97, 58% female, M_age = 13.03, SD_age = 2.82). We measured attention bias to negative versus non-negative emotional faces during a passive viewing task. We employed bifactor analysis to parse the unique and shared variance of anxiety and irritability symptoms from self- and parent-report questionnaires. Negative affectivity is the derived latent factor reflecting shared variance of anxiety and irritability. We found that higher negative affectivity was associated with looking longer at negative versus non-negative faces, reflecting a shared mechanism of anxiety and irritability. This finding suggests that modification of elevated attention to negative emotional faces may represent a common potential treatment target of anxiety and irritability.

Theory of Mind as a Mechanism That Accounts for the Continuity or Discontinuity of Behavioral Inhibition: A Developmentally Informed Model of Risk for Social Anxiety

Research has established that children with high levels of early behavioral inhibition (BI) - a subdued, timid, fearful response to novel or mildly challenging stimuli or events - are at an elevated risk for social anxiety in later childhood and adolescence. Yet, substantial heterogeneity has been documented in those developmental trajectories; consequently, understanding factors that moderate children's paths from early BI to social anxiety is an important goal. We proposed that the association between children's BI at toddler age and social anxiety at early school age is (a) mediated by their BI at preschool age, and (b) moderated by the level of social understanding, or Theory of Mind (ToM). In 102 typically developing community children, we observed BI in the laboratory at age 2 and 4.5 in "Risk Room" paradigms and assessed ToM at age 4.5 and 5.5 using false belief tasks. Mothers and fathers rated children's social anxiety symptoms at age 6.5. We supported the proposed moderated mediation model, with the path from BI at age 2 to BI at age 4.5 to social anxiety at age 6.5 unfolding only for children whose ToM abilities were relatively low, but not for those whose ToM abilities were relatively high. Results also supported a curvilinear relation between ToM and social anxiety, which highlights the risk of elevated social anxiety for children with extremely low ToM abilities. Taken together, proficiency in mindreading may help inhibited children navigate social environments and thus reduce risks for social anxiety.