Contextual startle responses moderate the relation between behavioral inhibition and anxiety in middle childhood

Understanding anxiety symptoms as aberrant defensive responding along the threat imminence continuum

Threat-anticipatory defensive responses have evolved to promote survival in a dynamic world. While inherently adaptive, aberrant expression of defensive responses to potential threat could manifest as pathological anxiety, which is prevalent, impairing, and associated with adverse outcomes. Extensive translational neuroscience research indicates that normative defensive responses are organized by threat imminence, such that distinct response patterns are observed in each phase of threat encounter and orchestrated by partially conserved neural circuitry. Anxiety symptoms, such as excessive and pervasive worry, physiological arousal, and avoidance behavior, may reflect aberrant expression of otherwise normative defensive responses, and therefore follow the same imminence-based organization. Here, empirical evidence linking aberrant expression of specific, imminence-dependent defensive responding to distinct anxiety symptoms is reviewed, and plausible contributing neural circuitry is highlighted. Drawing from translational and clinical research, the proposed framework informs our understanding of pathological anxiety by grounding anxiety symptoms in conserved psychobiological mechanisms. Potential implications for research and treatment are discussed.

Annual Research Review: Developmental pathways linking early behavioral inhibition to later anxiety

Behavioral Inhibition is a temperament identified in the first years of life that enhances the risk for development of anxiety during late childhood and adolescence. Amongst children characterized with this temperament, only around 40 percent go on to develop anxiety disorders, meaning that more than half of these children do not. Over the past 20 years, research has documented within-child and socio-contextual factors that support differing developmental pathways. This review provides a historical perspective on the research documenting the origins of this temperament, its biological correlates, and the factors that enhance or mitigate risk for development of anxiety. We review as well, research findings from two longitudinal cohorts that have identified moderators of behavioral inhibition in understanding pathways to anxiety. Research on these moderators has led us to develop the Detection and Dual Control (DDC) framework to understand differing developmental trajectories among behaviorally inhibited children. In this review, we use this framework to explain why and how specific cognitive and socio-contextual factors influence differential pathways to anxiety versus resilience.

Effects of early childhood behavioral inhibition and parental anxiety disorder on adolescents' startle response to predictable and unpredictable threat

Numerous studies in children, adolescents and adults have reported that anxiety disorders and symptoms are associated with greater threat-potentiated startle responses. This suggests that it may also be related to risk factors that have been implicated in the genesis of anxiety disorders. Therefore, we examined the roles of early childhood temperamental behavioral inhibition (BI) and parental history of anxiety disorders in predicting threat-potentiated startle response in a community sample of 346 adolescents. Parental history of anxiety disorders moderated the effects of BI on subsequent startle responses. For both total startle response and unpredictable threat startle potentiation, higher levels of BI at age 3 predicted larger startle responses at age 15, but only among offspring of parents with a history of anxiety disorders. Among offspring of parents with no lifetime history of anxiety disorder, BI was unrelated to startle magnitude. These findings were evident even after adjusting for youth's biological sex, concurrent anxiety symptoms, and lifetime history of anxiety disorders. In contrast, neither BI nor parental anxiety significantly predicted startle potentiation to predictable threat. These findings have implications for tracing pathways to the development of anxiety disorders.

Temperamental risk for anxiety: emerging work on the infant brain and later neurocognitive development

Behavioral inhibition (BI), an infant temperament characterized by distress to novelty, is amongst the strongest early risk markers for future anxiety. In this review, we highlight three ways that recent research elucidates key details about the pathophysiology of anxiety in individuals with BI. First, atypical amygdala connectivity during infancy may be related to BI. Second, developmental shifts in cognitive control may portend risk for anxiety for children with BI. Lastly, distinct cognitive control processes moderate the BI-anxiety relation in different ways. Studying the intersection of these three streams of work may inform prevention or intervention work.

Understanding the Emergence of Social Anxiety in Children With Behavioral Inhibition

Behavioral inhibition (BI) is a temperament characterized in early childhood by distress to novelty and avoidance of unfamiliar people, and it is one of the best-known risk factors for the development of social anxiety. However, nearly 60% of children with BI do not go on to meet criteria for social anxiety disorder. In this review we present an approach to understanding differential developmental trajectories among children with BI. We review research using laboratory-based tasks that isolate specific attention processes that enhance versus mitigate risk for social anxiety among behaviorally inhibited children and studies that suggest that BI is associated with heightened detection of novelty or threat. Moreover, stimulus-driven control processes, which we term "automatic control," increase the probability that behaviorally inhibited children display socially reticent behavior and develop social anxiety. In contrast, goal-driven control processes, which we term "planful control," decrease risk for anxiety. We suggest that these three categories of processes (detection, automatic control, and planful control) function together to determine whether behaviorally inhibited children are able to flexibly regulate their initial reactions to novelty, and in turn, decrease risk for social anxiety. Although laboratory-based tasks have identified these processes underlying risk and resilience, the challenge is linking them to the emotions, thoughts, and behaviors of behaviorally inhibited children in real-world contexts.

Startle to neutral, not negative stimuli: A neurophysiological correlate of behavioral inhibition in young children

A putative biomarker of anxiety risk, the startle response is typically enhanced by negative compared to neutral emotion modulation in adults, but remains understudied in children. To determine the extent to which neutral, negative, and positively valenced emotional conditions modulate startle response in early life, a child-friendly film paradigm was used to vary emotion across these conditions during startle induction in sixty-four 4- to 7-year-old children. Association of emotion-modulated startle with parent-reported anxiety symptom severity and child behavioral inhibition, a risk factor for anxiety problems, were assessed. Analyses revealed no difference in startle magnitude during negative compared to neutral film clips. By contrast, startle during both negative and neutral conditions was greater than startle during the positive condition. Larger startle magnitude during the neutral condition associated with higher levels of child behavioral inhibition (BI). These results are consistent with possible immaturity of startle response in young children, and suggest that startle amplitude in more emotionally ambiguous, neutral conditions could serve as an early biomarker for anxiety risk.

Prospective Association between Childhood Behavioral Inhibition and Anxiety: a Meta-Analysis

Behavioral inhibition (BI) is a risk factor for anxiety. However, the estimates of the strength of this association vary widely. In addition, while BI is a strong predictor of social anxiety disorder (SAD), its association with other anxiety disorders is unclear. The current study sought to establish the relationship between BI and anxiety and to quantify this association for a range of anxiety disorders. We searched PsycInfo, PubMed and Embase for articles published before May 18th, 2019 using search terms for BI, anxiety and prospective study design. We selected articles which assessed the prospective relationship between BI in childhood and anxiety. Using random-effects meta-analysis with robust variance estimation, which allowed for the inclusion of multiple follow-ups of the same sample, we established the association between BI and any anxiety. We also explored the association between BI and individual anxiety disorders. Data from 27 studies consisting of 35 follow-ups of 20 unique samples indicated that BI prospectively increases the odds of anxiety (OR = 2.80, 95% CI 2.03 to 3.86, p < 0.001). There was also a positive association between BI and all individual anxiety disorders, with effect sizes ranging from small in the case of specific phobia (OR = 1.49, 95% CI 1.03 to 2.14, p = 0.03) to large in the case of SAD (OR = 5.84, 95% CI 3.38 to 10.09, p < 0.001). BI in early childhood is a strong risk factor for anxiety. Targeting BI may help reduce the number of children who will develop anxiety disorders.

Levels of early-childhood behavioral inhibition predict distinct neurodevelopmental pathways to pediatric anxiety

BACKGROUND

Anxiety symptoms gradually emerge during childhood and adolescence. Individual differences in behavioral inhibition (BI), an early-childhood temperament, may shape developmental paths through which these symptoms arise. Cross-sectional research suggests that level of early-childhood BI moderates associations between later anxiety symptoms and threat-related amygdala-prefrontal cortex (PFC) circuitry function. However, no study has characterized these associations longitudinally. Here, we tested whether level of early-childhood BI predicts distinct evolving associations between amygdala-PFC function and anxiety symptoms across development.

METHODS

Eighty-seven children previously assessed for BI level in early childhood provided data at ages 10 and/or 13 years, consisting of assessments of anxiety and an fMRI-based dot-probe task (including threat, happy, and neutral stimuli). Using linear-mixed-effects models, we investigated longitudinal changes in associations between anxiety symptoms and threat-related amygdala-PFC connectivity, as a function of early-childhood BI.

RESULTS

In children with a history of high early-childhood BI, anxiety symptoms became, with age, more negatively associated with right amygdala-left dorsolateral-PFC connectivity when attention was to be maintained on threat. In contrast, with age, low-BI children showed an increasingly positive anxiety-connectivity association during the same task condition. Behaviorally, at age 10, anxiety symptoms did not relate to fluctuations in attention bias (attention bias variability, ABV) in either group; by age 13, low-BI children showed a negative anxiety-ABV association, whereas high-BI children showed a positive anxiety-ABV association.

CONCLUSIONS

Early-childhood BI levels predict distinct neurodevelopmental pathways to pediatric anxiety symptoms. These pathways involve distinct relations among brain function, behavior, and anxiety symptoms, which may inform diagnosis and treatment.

Extending the neurocircuitry of behavioural inhibition: a role for the bed nucleus of the stria terminalis in risk for anxiety disorders

Behavioural inhibition is a biologically based risk factor for anxiety disorders. Children with behavioural inhibition are shy, cautious and avoidant of new situations. Much research on behavioural inhibition has focused on the amygdala as an underlying neural substrate and has identified differences in amygdala function and volume; however, amygdala findings have yet to lead to meaningful interventions for prevention or treatment of anxiety disorders. The bed nucleus of the stria terminalis (BNST) is a prime candidate to be a neural substrate of behavioural inhibition, given current evidence of BNST function and development in human research and animal models. Children with behavioural inhibition have an increased startle response to safety cues and an increased cortisol response to social evaluative situations, both of which are mediated by the BNST. In rodents, activation of the BNST underlies contextual fear responses and responses to uncertain and sustained threat. Non-human primates with anxious temperament (the macaque equivalent of behavioural inhibition) have increased BNST activity to ambiguous social situations, and activity of the BNST in anxious temperament is significantly heritable. Importantly, the BNST is sexually dimorphic and continues to develop into adulthood, paralleling the development of anxiety disorders in humans. Together, these findings suggest that further investigation of the BNST in behavioural inhibition is necessary and may lead to new avenues for the prevention and treatment of anxiety disorders.

Giving Voice to Vulnerable Children: Machine Learning Analysis of Speech Detects Anxiety and Depression in Early Childhood

Childhood anxiety and depression often go undiagnosed. If left untreated these conditions, collectively known as internalizing disorders, are associated with long-term negative outcomes including substance abuse and increased risk for suicide. This paper presents a new approach for identifying young children with internalizing disorders using a 3-min speech task. We show that machine learning analysis of audio data from the task can be used to identify children with an internalizing disorder with 80% accuracy (54% sensitivity, 93% specificity). The speech features most discriminative of internalizing disorder are analyzed in detail, showing that affected children exhibit especially low-pitch voices, with repeatable speech inflections and content, and high-pitched response to surprising stimuli relative to controls. This new tool is shown to outperform clinical thresholds on parent-reported child symptoms, which identify children with an internalizing disorder with lower accuracy (67-77% versus 80%), and similar specificity (85-100% versus 93%), and sensitivity (0-58% versus 54%) in this sample. These results point toward the future use of this approach for screening children for internalizing disorders so that interventions can be deployed when they have the highest chance for long-term success.

Approach, avoidance, and the detection of conflict in the development of behavioral inhibition

Motivation has played an integral role in understanding personality development. Two motivational systems, one associated with seeking reward (approach motivation) and one associated with avoidance of threat (avoidance motivation), have been theorized to represent individual differences in behavioral responses to the environment. However, contextual factors, particularly those with a high degree of novelty, ambiguity, and unpredictability, may simultaneously activate both systems, thereby causing approach-avoidance conflict. The resulting behavior, commonly called inhibition, is characterized by an inability to engage in motivated, goal-directed behavior and is theorized to reflect a core component of anxiety. A form of inhibition observed in childhood, behavioral inhibition (BI), is a relatively stable temperamental profile characterized by negative affect in response to unfamiliar and unpredictable contexts and is a risk factor for anxiety. Our review draws from findings in clinical and cognitive neuroscience to argue that BI reflects an increased sensitivity of both approach and avoidance motivational systems, thereby increasing the likelihood of approach-avoidance conflict within the context of unfamiliar or unpredictable stimuli and environments. Such motivational conflict activates neural systems associated with conflict monitoring, which leads to increases in arousal (e.g., sympathetic nervous system activity) and onlooking behavior, two commonly observed characteristics of childhood BI.

Kinds of individuals defined by patterns of variables

This paper argues that investigators should consider replacing the popular practice of comparing individuals varying in gender, social class, and/or ethnicity on one or more continuous measures with a search for kinds of individuals defined by patterns of properties that include not only their values on outcome measures but also their gender, social class, and ethnicity. Investigators who believe that a particular predictor contributes to an outcome independent of the gender, class, or ethnicity of the participants often implement statistical procedures that promise to remove the contributions of the above categories. These analyses lead to misleading conclusions when the controlled category is correlated with the dependent measures. The final sections summarize the properties of genders, classes, and ethnic groups that make distinctive contributions to many psychological outcomes. The paper ends by noting that a society's ethical beliefs constitute a defensible basis for ignoring the biological properties associated with these categories in order to allow members of these groups access to whatever educational or occupational goals they desire.

Assessing the interplay of childhood adversities with more recent stressful life events and conditions in predicting panic pathology among adults from the general population

BACKGROUND

Although research suggests that (a) childhood adversities and more recent stressful life events/conditions are risk factors for panic pathology and that (b) early life stress increases vulnerability to later psychopathology, it remains unclear whether childhood adversities amplify the association between more recent stressful life events/conditions and panic pathology.

METHODS

Data were derived from a general population sample (Study of Health in Pomerania, SHIP). Lifetime panic pathology was assessed with the Munich Composite International Diagnostic Interview (M-CIDI). Childhood adversities (emotional, physical and sexual abuse; emotional and physical neglect) were assessed with the Childhood Trauma Questionnaire (CTQ). More recent separation/loss events and long-lasting stressful conditions were assessed with the Stralsund Life Event List (SEL). Individuals with lifetime panic pathology (fearful spell, panic attack or panic disorder, N = 286) were compared to controls without any psychopathology (N = 286, matched for sex and age).

RESULTS

Conditional logistic regressions revealed that childhood adversities as well as more recent separation/loss events and long-lasting stressful conditions were associated with panic pathology (OR 1.1-2.5). Moreover, more recent separation/loss events - but not long-lasting stressful conditions - interacted statistically with each of the examined childhood adversities except for sexual abuse in predicting panic pathology (OR 1.1-1.3). That is, separation/loss events were associated more strongly with panic pathology among individuals with higher childhood adversities.

LIMITATIONS

Data were assessed retrospectively and might be subject to recall biases.

CONCLUSIONS

Findings suggest that early childhood adversities amplify the risk of developing panic pathology after experiencing separation or loss events.

Annual Research Review: An expanded account of information-processing mechanisms in risk for child and adolescent anxiety and depression

BACKGROUND

Anxiety and depression occurring during childhood and adolescence are common and costly. While early-emerging anxiety and depression can arise through a complex interplay of 'distal' factors such as genetic and environmental influences, temperamental characteristics and brain circuitry, the more proximal mechanisms that transfer risks on symptoms are poorly delineated. Information-processing biases, which differentiate youth with and without anxiety and/or depression, could act as proximal mechanisms that mediate more distal risks on symptoms. This article reviews the literature on information-processing biases, their associations with anxiety and depression symptoms in youth and with other distal risk factors, to provide direction for further research.

METHODS

Based on strategic searches of the literature, we consider how youth with and without anxiety and/or depression vary in how they deploy attention to social-affective stimuli, discriminate between threat and safety cues, retain memories of negative events and appraise ambiguous information. We discuss how these information-processing biases are similarly or differentially expressed on anxiety and depression and whether these biases are linked to genetic and environmental factors, temperamental characteristics and patterns of brain circuitry functioning implicated in anxiety and depression.

FINDINGS

Biases in attention and appraisal characterise both youth anxiety and depression but with some differences in how these are expressed for each symptom type. Difficulties in threat-safety cue discrimination characterise anxiety and are understudied in depression, while biases in the retrieval of negative and overgeneral memories have been observed in depression but are understudied in anxiety. Information-processing biases have been studied in relation to some distal factors but not systematically, so relationships remain inconclusive.

CONCLUSIONS

Biases in attention, threat-safety cue discrimination, memory and appraisal may characterise anxiety and/or depression risk. We discuss future research directions that can more systematically test whether these biases act as proximal mechanisms that mediate other distal risk factors.

Dispositional negativity: An integrative psychological and neurobiological perspective

Dispositional negativity-the propensity to experience and express more frequent, intense, or enduring negative affect-is a fundamental dimension of childhood temperament and adult personality. Elevated levels of dispositional negativity can have profound consequences for health, wealth, and happiness, drawing the attention of clinicians, researchers, and policymakers. Here, we highlight recent advances in our understanding of the psychological and neurobiological processes linking stable individual differences in dispositional negativity to momentary emotional states. Self-report data suggest that 3 key pathways-increased stressor reactivity, tonic increases in negative affect, and increased stressor exposure-explain most of the heightened negative affect that characterizes individuals with a more negative disposition. Of these 3 pathways, tonically elevated, indiscriminate negative affect appears to be most central to daily life and most relevant to the development of psychopathology. New behavioral and biological data provide insights into the neural systems underlying these 3 pathways and motivate the hypothesis that seemingly "tonic" increases in negative affect may actually reflect increased reactivity to stressors that are remote, uncertain, or diffuse. Research focused on humans, monkeys, and rodents suggests that this indiscriminate negative affect reflects trait-like variation in the activity and connectivity of several key brain regions, including the central extended amygdala and parts of the prefrontal cortex. Collectively, these observations provide an integrative psychobiological framework for understanding the dynamic cascade of processes that bind emotional traits to emotional states and, ultimately, to emotional disorders and other kinds of adverse outcomes. (PsycINFO Database Record

Error-related brain activity is related to aversive potentiation of the startle response in children, but only the ERN is associated with anxiety disorders

Identifying biomarkers that characterize developmental trajectories leading to anxiety disorders will likely improve early intervention strategies as well as increase our understanding of the etiopathogenesis of these disorders. The error-related negativity (ERN), an event-related potential that occurs during error commission, is increased in anxious adults and children-and has been shown to predict the onset of anxiety disorders across childhood. The ERN has therefore been suggested as a biomarker of anxiety. However, it remains unclear what specific processes a potentiated ERN may reflect. We have recently proposed that the ERN may reflect trait-like differences in threat sensitivity; however, very few studies have examined the ERN in relation to other indices of this construct. In the current study, the authors measured the ERN, as well as affective modulation of the startle reflex, in a large sample (N = 155) of children. Children characterized by a large ERN also exhibited greater potentiation of the startle response in the context of unpleasant images, but not in the context of neutral or pleasant images. In addition, the ERN, but not startle response, related to child anxiety disorder status. These results suggest a relationship between error-related brain activity and aversive potentiation of the startle reflex during picture viewing-consistent with the notion that both measures may reflect individual differences in threat sensitivity. However, results suggest the ERN may be a superior biomarker of anxiety in children. (PsycINFO Database Record

Contributions of the Central Extended Amygdala to Fear and Anxiety

It is widely thought that phasic and sustained responses to threat reflect dissociable circuits centered on the central nucleus of the amygdala (Ce) and the bed nucleus of the stria terminalis (BST), the two major subdivisions of the central extended amygdala. Early versions of this hypothesis remain highly influential and have been incorporated into the National Institute of Mental Health Research Research Domain Criteria framework. However, new observations encourage a different perspective. Anatomical studies show that the Ce and BST form a tightly interconnected unit, where different kinds of threat-relevant information can be integrated and used to assemble states of fear and anxiety. Imaging studies in humans and monkeys show that the Ce and BST exhibit similar functional profiles. Both regions are sensitive to a range of aversive challenges, including uncertain or temporally remote threat; both covary with concurrent signs and symptoms of fear and anxiety; both show phasic responses to short-lived threat; and both show heightened activity during sustained exposure to diffusely threatening contexts. Mechanistic studies demonstrate that both regions can control the expression of fear and anxiety during sustained exposure to diffuse threat. These observations compel a reconsideration of the central extended amygdala's contributions to fear and anxiety and its role in neuropsychiatric disease.