Increased anxiety during anticipation of unpredictable but not predictable aversive stimuli as a psychophysiologic marker of panic disorder

Protective Factors Predict Resilient Outcomes in Clinical High-Risk Youth with the Highest Individualized Psychosis Risk Scores

BACKGROUND AND HYPOTHESIS

Studying individuals at Clinical High Risk (CHR) for psychosis provides an opportunity to examine protective factors that predict resilient outcomes. Here, we present a model for the study of protective factors in CHR participants at the very highest risk for psychotic conversion based on the Psychosis Risk Calculator.

STUDY DESIGN

CHR participants (N = 572) from NAPLS3 were assessed on the Risk Calculator. Those who scored in the top half of the distribution and had 2 years of follow-up (N = 136) were divided into those who did not convert to psychosis (resilient, N = 90) and those who did (nonresilient, N = 46). Groups were compared based on candidate protective factors that were not part of the Risk Calculator. Better functional outcome was also examined as an outcome measure of resiliency. Study Results: Exploratory analyses suggest that Hispanic heritage, social engagement, desirable life experiences, premorbid functioning and IQ are all potential protective factors that predict resilient outcomes. Reduced startle reactivity, brain area and volume were also associated with greater resilience.

CONCLUSIONS

The primary focus of CHR research has been the risk and prediction of psychosis, while less is known about protective factors. Clearly, a supportive childhood environment, positive experiences, and educational enrichment may contribute to better premorbid functioning and brain development, which in turn contribute to more resilient outcomes. Therapies focused on enhancing protective factors in the CHR population are logical preventive interventions that may benefit this vulnerable population. Future CHR research might use similar models to develop a "protective index" to predict resilient outcomes.

Aversive contexts enhance defensive responses to conditioned threat

The ability to flexibly transition between defensive states is crucial for adaptive responding in life-threatening situations. Potentially threatening situations typically induce a sustained feeling of apprehension in association with hypervigilance, while acute threat is usually characterized by an intense and transient response to cope with the imminent danger. While potential and acute threat states have traditionally been viewed as mutually exclusive, this distinction is being challenged by a growing body of evidence suggesting a more complex interplay during simultaneous activation of these states. However, the interaction between potential and acute threat on a psychophysiological level remains elusive. To fill this gap, 94 healthy individuals participated in one of two contextual fear-conditioning paradigms. In both paradigms, a differential fear-learning phase was conducted, followed by a test phase in which the conditioned stimuli were presented in front of either conditioned or inherently aversive contextual images compared to neutral contexts. To capture defensive responses, we recorded subjective (threat and expectancy ratings) and physiological (electrodermal and cardiovascular) activity to the conditioned stimuli as a function of contextual threat. Besides indices of successful fear conditioning, our results revealed stronger threat and unconditioned stimulus expectancy ratings, cardiac deceleration, and skin conductance responses for threat and safety cues presented in inherently aversive compared to neutral contexts. Conditioned contexts had less impact on physiological responses to threat and safety cues than inherently aversive contexts. These findings provide new insights into the additive nature of defensive responses to fear cues and situations of contextual threat.

Physiological correlates of anxiety in childhood and adolescence: A systematic review and meta-analysis

Anxiety is one of the most prevalent problems that affects children and adolescents. The vast majority of diagnostic tools for anxiety depend on written or verbal reports from children and adolescents or their significant others. The validity and reliability of such reports can be compromised by their subjective nature. Thus, there is growing interest in whether anxiety can be indexed with objective physiological measures. The key aim of this systematic review and meta-analysis was to determine which physiological measures are most reliably associated with elevated levels of anxiety amongst children and adolescents. Online databases (e.g., PsycINFO, Embase, Medline) were searched for relevant studies according to pre-determined criteria. Twenty-five studies comprising 2502 participants (N = 1160 with high anxiety) met inclusion, identifying 11 groups of physiological measures. Our meta-analysis revealed that skin conductance level is the most sensitive measure of anxiety (d = 0.83), followed by electromyography (EMG) measures (d = 0.71) and skin conductance response (d = 0.58). However, the included studies varied in terms of subjective measures, study designs, experimental task measures, and physiological measures. Consideration of these differences in methodology offer potential directions for future research.

Identification of group differences in predictive anticipatory biasing of pain during uncertainty: preparing for the worst but hoping for the best

ABSTRACT

Pain anticipation during conditions of uncertainty can unveil intrinsic biases, and understanding these biases can guide pain treatment interventions. This study used machine learning and functional magnetic resonance imaging to predict anticipatory responses in a pain anticipation experiment. One hundred forty-seven participants that included healthy controls (n = 57) and individuals with current and/or past mental health diagnosis (n = 90) received cues indicating upcoming pain stimuli: 2 cues predicted high and low temperatures, while a third cue introduced uncertainty. Accurate differentiation of neural patterns associated with specific anticipatory conditions was observed, involving activation in the anterior short gyrus of the insula and the nucleus accumbens. Three distinct response profiles emerged: subjects with a negative bias towards high pain anticipation, those with a positive bias towards low pain anticipation, and individuals whose predictions during uncertainty were unbiased. These profiles remained stable over one year, were consistent across diagnosed psychopathologies, and correlated with cognitive coping styles and underlying insula anatomy. The findings suggest that individualized and stable pain anticipation occurs in uncertain conditions.

Exploring the 'black box' of anxiety: An ERP study of non-consciously triggered fear generalization

Individuals with anxiety disorders frequently display heightened fear responses, even in situations where there is no imminent danger. We hypothesize that these irrational fear responses are related to automatic processing of fear generalization. The initial automatic detection of stimuli often operates at a non-conscious level. However, whether fear generalization can occur when the cues are not perceived consciously remains unclear. The current study investigated the neurocognitive mechanisms underlying fear conditioning and its non-conscious and conscious generalization using a backward masking paradigm, combined with analysis of event-related potentials from electroencephalographic recordings. Behaviorally, participants showed heightened shock expectancy in response to non-conscious perceived generalization stimuli compared to those perceived consciously. Nonetheless, participants could not consciously distinguish between danger and safe cues in non-conscious trials. Physiologically, danger cues evoked larger frontal N1 amplitudes than safety cues in non-conscious trials, suggesting enhanced attention vigilance towards danger cues in the early sensory processing stage. Meanwhile, when fear generalization was conscious, it was accompanied by a larger P2 amplitude, indicating attention orientation or stimulus evaluation. In addition, fear conditioning was associated with sustained discrimination on P2, P3, and LPP. These findings collectively suggest that non-conscious fear generalization occurs at the neural level, yet additional control conditions are required to confirm this phenomenon on the US expectancy. Thus, non-consciously fear generalization may represent a mechanism that could trigger automatic irrational fear, highlighting the need for further research to explore therapeutic targets in anxiety disorders.

A single base pair substitution in zebrafish distinguishes between innate and acute startle behavior regulation

Behavioral thresholds define the lowest stimulus intensities sufficient to elicit a behavioral response. Establishment of baseline behavioral thresholds during development is critical for proper responses throughout the animal's life. Despite the relevance of such innate thresholds, the molecular mechanisms critical to establishing behavioral thresholds during development are not well understood. The acoustic startle response is a conserved behavior whose threshold is established during development yet is subsequently acutely regulated. We have previously identified a zebrafish mutant line (escapist) that displays a decreased baseline or innate acoustic startle threshold. Here, we identify a single base pair substitution on Chromosome 25 located within the coding sequence of the synaptotagmin 7a (syt7a) gene that is tightly linked to the escapist acoustic hypersensitivity phenotype. By generating animals in which we deleted the syt7a open reading frame, and subsequent complementation testing with the escapist line, we demonstrate that loss of syt7a function is not the cause of the escapist behavioral phenotype. Nonetheless, escapist mutants provide a powerful tool to decipher the overlap between acute and developmental regulation of behavioral thresholds. Extensive behavioral analyses reveal that in escapist mutants the establishment of the innate acoustic startle threshold is impaired, while regulation of its acute threshold remains intact. Moreover, our behavioral analyses reveal a deficit in baseline responses to visual stimuli, but not in the acute regulation of responses to visual stimuli. Together, this work eliminates loss of syt7a as causative for the escapist phenotype and suggests that mechanisms that regulate the establishment of behavioral thresholds in escapist larvae can operate independently from those regulating acute threshold regulation.

In the anticipation of threat: Neural regulatory activity indicated by delta-beta correlation and its relation to anxiety

The anticipation of oncoming threats is emotionally challenging and related to anxiety. The current study aimed to investigate the neural regulatory processes during the anticipatory preparations in stressful situations in relation to trait anxiety, especially in an uncertainty-related stressful situation. To this end, we measured within-subjects delta-beta amplitude-amplitude correlation (AAC) and phase-amplitude coupling (PAC) with electroencephalography using a well-defined stress-inducing paradigm in 28 high-trait-anxiety (HTA) and 29 low-trait-anxiety (LTA) college students. Specifically, a threat probability task was conducted, where participants anticipated the future stimuli under the uncertain (i.e., an average of 50% electric shocks), certain (i.e., 100% electric shocks) and no threat conditions, as well as a resting state task. Results showed a generally larger delta-beta AAC in the LTA group relative to the HTA group across conditions, supporting the hypothesis that delta-beta AAC reflects the efficiency of stress regulation and trait anxiety could compromise this adaptive regulatory activity. Furthermore, a larger delta-beta PAC was found under the uncertain threat condition relative to the no threat condition, indicating the sensitivity of delta-beta PAC in reflecting state anxiety. These findings indicate that while delta-beta AAC is more related to trait anxiety and could distinguish between high and low trait anxiety irrespective of conditions, delta-beta PAC is more related to state anxiety and is sensitive enough to detect the uncertainty-related anxious state.

Sleep quality impacts the link between reactivity to uncertain threat and anxiety and alcohol use in youth

Individual differences in reactivity to unpredictable threat (U-threat) have repeatedly been linked to symptoms of anxiety and drinking behavior. An emerging theory is that individuals who are hyper-reactive to U-threat experience chronic anticipatory anxiety, hyperarousal, and are vulnerable to excessive alcohol use via negative reinforcement processes. Notably, anxiety and alcohol use commonly relate to disruptions in sleep behavior and recent findings suggest that sleep quality may impact the link between reactivity to U-threat and psychiatric symptoms and behaviors. The aim of the current study was to examine the unique and interactive effects of reactivity to U-threat and sleep quality on anxiety symptoms and drinking behavior in a cohort of youth, ages 16-19 years. Participants (N = 112) completed a well-validated threat-of-shock task designed to probe individual differences in reactivity to U-threat and predictable threat (P-threat). Startle eyeblink potentiation was recorded during the task as an index of aversive reactivity. Participants also completed well-validated self-report measures of anxiety and depression symptoms, lifetime alcohol use, and current sleep quality. Results revealed significant startle reactivity to U-threat by sleep quality interactions on anxiety symptoms and lifetime drinking behavior. At high levels of sleep disturbance (only), greater reactivity to U-threat was associated with greater anxiety symptoms and total number of lifetime alcoholic beverages. These results suggest that sensitivity to uncertainty and chronic hyperarousal increases anxiety symptoms and alcohol use behavior, particularly in the context of poor sleep quality.

A neural signature for the subjective experience of threat anticipation under uncertainty

Uncertainty about potential future threats and the associated anxious anticipation represents a key feature of anxiety. However, the neural systems that underlie the subjective experience of threat anticipation under uncertainty remain unclear. Combining an uncertainty-variation threat anticipation paradigm that allows precise modulation of the level of momentary anxious arousal during functional magnetic resonance imaging (fMRI) with multivariate predictive modeling, we train a brain model that accurately predicts subjective anxious arousal intensity during anticipation and test it across 9 samples (total n = 572, both gender). Using publicly available datasets, we demonstrate that the whole-brain signature specifically predicts anxious anticipation and is not sensitive in predicting pain, general anticipation or unspecific emotional and autonomic arousal. The signature is also functionally and spatially distinguishable from representations of subjective fear or negative affect. We develop a sensitive, generalizable, and specific neuroimaging marker for the subjective experience of uncertain threat anticipation that can facilitate model development.

Facing ambiguity: Social threat sensitivity mediates the association between peer victimization and adolescent anxiety

Peer victimization is a developmentally salient stressor that elevates adolescents' risk for anxiety disorders. However, modifiable mechanisms that explain this link and can be targeted via therapeutic interventions remain poorly understood. Drawing from psychobiological models implicating aberrant threat sensitivity in the development and maintenance of psychopathology, the current study investigated sensitivity to peer-related social threats as a mechanism underlying the association between peer victimization and anxiety. A sample of 197 dyads of early adolescents (M age = 12.02; 46% female) and parents/guardians (M age = 41.46; 90% female) completed online surveys assessing peer victimization, sensitivity to potential (i.e., ambiguous) social threats, and anxiety. Controlling for potentially confounding demographic and psychosocial factors, both self- and parent-reported peer victimization were positively associated with adolescent anxiety symptoms. Additionally, there were significant indirect effects from self- and parent-reported peer victimization to anxiety via social threat sensitivity. Supplemental analyses indicated unique effects of covert, but not overt, peer victimization on social threat sensitivity and anxiety. The findings provide initial evidence that peer victimization experiences lower adolescents' threshold for interpreting threats in ambiguous social situations, which contributes to heightened anxiety. These results implicate social threat sensitivity as a potential therapeutic target for interrupting links from peer victimization to psychological distress.

Knowledge of Threat Biases Perceptual Decision Making in Anxiety: Evidence From Signal Detection Theory and Drift Diffusion Modeling

Background

Threat biases are considered key factors in the development and maintenance of anxiety. However, these biases are poorly operationalized and remain unquantified. Furthermore, it is unclear whether and how prior knowledge of threat and its uncertainty induce these biases and how they manifest in anxiety.

Method

Participants (n = 55) used prestimulus cues to decide whether the subsequently presented stimuli were threatening or neutral. The cues either provided no information about the probability (high uncertainty) or indicated high probability (low uncertainty) of encountering threatening or neutral targets. We used signal detection theory and hierarchical drift diffusion modeling to quantify bias.

Results

High-uncertainty threat cues improved discrimination of subsequent threatening and neutral stimuli more than neutral cues. However, anxiety was associated with worse discrimination of threatening versus neutral stimuli following high-uncertainty threat cues. Using hierarchical drift diffusion modeling, we found that threat cues biased decision making not only by shifting the starting point of evidence accumulation toward the threat decision but also by increasing the efficiency with which sensory evidence was accumulated for both threat-related and neutral decisions. However, higher anxiety was associated with a greater shift of starting point toward the threat decision but not with the efficiency of evidence accumulation.

Conclusions

Using computational modeling, these results highlight the biases by which knowledge regarding uncertain threat improves perceptual decision making but impairs it in case of anxiety.

Attenuation of Anxiety-Potentiated Startle After Treatment With Escitalopram or Mindfulness Meditation in Anxiety Disorders

BACKGROUND

Biological markers for anxiety disorders may further understanding of disorder pathophysiology and suggest potential targeted treatments. The fear-potentiated startle (FPS) (a measure of startle to predictable threat) and anxiety-potentiated startle (APS) (startle to unpredictable threat) laboratory paradigm has been used to detect physiological differences in individuals with anxiety disorders compared with nonanxious control individuals, and in pharmacological challenge studies in healthy adults. However, little is known about how startle may change with treatment for anxiety disorders, and no data are available regarding alterations due to mindfulness meditation training.

METHODS

Ninety-three individuals with anxiety disorders and 66 healthy individuals completed 2 sessions of the neutral, predictable, and unpredictable threat task, which employs a startle probe and the threat of shock to assess moment-by-moment fear and anxiety. Between the two testing sessions, patients received randomized 8-week treatment with either escitalopram or mindfulness-based stress reduction.

RESULTS

APS, but not FPS, was higher in participants with anxiety disorders compared with healthy control individuals at baseline. Further, there was a significantly greater decrease in APS for both treatment groups compared with the control group, with the patient groups showing reductions bringing them into the range of control individuals at the end of the treatment.

CONCLUSIONS

Both anxiety treatments (escitalopram and mindfulness-based stress reduction) reduced startle potentiation during unpredictable (APS) but not predictable (FPS) threat. These findings further validate APS as a biological correlate of pathological anxiety and provide physiological evidence for the impact of mindfulness-based stress reduction on anxiety disorders, suggesting that there may be comparable effects of the two treatments on anxiety neurocircuitry.

No influence of threat uncertainty on fear generalization

Fear overgeneralization and perceived uncertainty about future outcomes have been suggested as risk factors for clinical anxiety. However, little is known regarding how they influence each other. In this study, we investigated whether different levels of threat uncertainty influence fear generalization. Three groups of healthy participants underwent a differential fear conditioning protocol followed by a generalization test. All groups learned to associate one female face (conditioned stimulus, CS+) with a female scream (unconditioned stimulus, US), whereas the other face (CS-) was not associated with the scream. In order to manipulate threat uncertainty, one group (low uncertainty, n = 26) received 80%, the second group (moderate uncertainty, n = 32) received 60%, and the third group (high uncertainty, n = 30) 40% CS-US contingency. In the generalization test, all groups saw CS+ and CS- again along with four morphs resembling the CSs in steps of 20%. Subjective (expectancy, valence, and arousal ratings), psychophysiological (skin conductance response, SCR), and visuocortical (steady-state visual evoked potentials, ssVEPs) indices of fear were registered. Participants expected the US according to their reinforcement schedules and the discriminative responses to CS+/CS- increased with more uncertainty in skin conductance. However, acquisition of conditioned fear was not evident in ssVEPs. During the generalization test, we found no effect of threat uncertainty in any of the measured variables, but the strength of generalization for threat expectancy ratings was positively correlated with dispositional intolerance of uncertainty. This study suggests that mere threat uncertainty does not modulate fear generalization.

Threat effects on cognitive systems: Testing links to aggression proneness

The biobehavioral study of aggression has implications for expanding our understanding of transdiagnostic processes that increase risk for disinhibited behaviors. Toward this end, our study tested tenets from the process model of aggression (Verona & Bresin, 2015). First, we expected that the predictability of threat would differentially alter cognitive networks, including attentional alerting and executive control. Second, we examined the moderating effects of self- and informant reports of aggression on threat-related changes in cognitive functioning. Using event-related potential (ERP) measures of cognitive-attentional processes, 143 community individuals participated in a well-validated and translational threat manipulation (NPU) task (Schmitz & Grillon, 2012) while completing the Attention Network Test (Fan et al., 2002). Analyses revealed that relatively unpredictable threat quickened alerting-related reaction time, whereas predictable threat interfered with processing of flanker task stimuli. The results, however, failed to show reliable relationships between aggression proneness and threat-related cognitive alterations. The findings fit with a broader literature on cognitive and behavioral outputs of threat activation and provide fruitful avenues for better understanding threat-related aggression. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Neurobiological sensitivity to unpredictable threat and familial risk for the internalizing and externalizing spectra in adolescents

BACKGROUND

Adolescence is a key developmental period for the emergence of psychiatric disorders. However, there is still no consensus on the core mechanisms of dysfunction in youth. Neurobiological sensitivity to unpredictable threat has been associated with several psychiatric disorders in adults. The present study examined adolescent defensive motivation (startle reflex) and attention (event-related potentials) in anticipation of unpredictable threat in relation to both adolescent and maternal (i.e. familial risk) internalizing and externalizing spectra.

METHODS

The sample included 395 15-year-old adolescents and their biological mothers. Adolescent startle potentiation and probe P300 suppression (indicating increased attention to threat) were measured in anticipation of predictable and unpredictable threat. Adolescent and maternal lifetime history of psychiatric disorders were assessed via semi-structured diagnostic interviews, and confirmatory factor analysis was used to model internalizing and externalizing spectra.

RESULTS

The adolescent internalizing spectrum was positively associated with adolescent startle potentiation and probe P300 suppression to unpredictable threat. Conversely, the adolescent externalizing spectrum was negatively associated with adolescent P300 suppression to unpredictable threat. The maternal internalizing spectrum was positively associated with adolescent startle potentiation to unpredictable threat and P300 suppression to both predictable and unpredictable threat. The maternal externalizing spectrum was negatively associated with adolescent startle potentiation to unpredictable threat and P300 suppression to both predictable and unpredictable threat. Adolescent and maternal internalizing and externalizing spectra were independently related to adolescent startle potentiation and P300 suppression.

CONCLUSIONS

Adolescent neurobiological sensitivity to unpredictable threat is associated with both personal history and familial risk for the internalizing and externalizing spectra.

A single base pair substitution on Chromosome 25 in zebrafish distinguishes between development and acute regulation of behavioral thresholds

Behavioral thresholds define the lowest stimulus intensities sufficient to elicit a behavioral response. Establishment of baseline behavioral thresholds during development is critical for proper responses throughout the animal's life. Despite the relevance of such innate thresholds, the molecular mechanisms critical to establishing behavioral thresholds during development are not well understood. The acoustic startle response is a conserved behavior whose threshold is established during development yet is subsequently acutely regulated. We have previously identified a zebrafish mutant line ( escapist ) that displays a decreased baseline or innate acoustic startle threshold. Here, we identify a single base pair substitution on Chromosome 25 located within the coding sequence of the synaptotagmin 7a ( syt7a ) gene that is tightly linked to the escapist acoustic hypersensitivity phenotype. By generating animals in which we deleted the syt7a open reading frame, and subsequent complementation testing with the escapist line, we demonstrate that loss of syt7a function is not the cause of the escapist behavioral phenotype. Nonetheless, escapist mutants provide a powerful tool to decipher the overlap between acute and developmental regulation of behavioral thresholds. Extensive behavioral analyses reveal that in escapist mutants the establishment of the innate acoustic startle threshold is impaired, while regulation of its acute threshold remains intact. Moreover, our behavioral analyses reveal a deficit in baseline responses to visual stimuli, but not in the acute regulation of responses to visual stimuli. Together, this work eliminates loss of syt7a as causative for the escapist phenotype and suggests that mechanisms that regulate the establishment of behavioral thresholds in escapist larvae can operate largely independently from those regulating acute threshold regulation.

Anxiety as a disorder of uncertainty: implications for understanding maladaptive anxiety, anxious avoidance, and exposure therapy

In cognitive-behavioral conceptualizations of anxiety, exaggerated threat expectancies underlie maladaptive anxiety. This view has led to successful treatments, notably exposure therapy, but is not consistent with the empirical literature on learning and choice alterations in anxiety. Empirically, anxiety is better described as a disorder of uncertainty learning. How disruptions in uncertainty lead to impairing avoidance and are treated with exposure-based methods, however, is unclear. Here, we integrate concepts from neurocomputational learning models with clinical literature on exposure therapy to propose a new framework for understanding maladaptive uncertainty functioning in anxiety. Specifically, we propose that anxiety disorders are fundamentally disorders of uncertainty learning and that successful treatments, particularly exposure therapy, work by remediating maladaptive avoidance from dysfunctional explore/exploit decisions in uncertain, potentially aversive situations. This framework reconciles several inconsistencies in the literature and provides a path forward to better understand and treat anxiety.

The effect of inherently threatening contexts on visuocortical engagement to conditioned threat

Fear and anxiety are crucial for adaptive responding in life-threatening situations. Whereas fear is a phasic response to an acute threat accompanied by selective attention, anxiety is characterized by a sustained feeling of apprehension and hypervigilance during situations of potential threat. In the current literature, fear and anxiety are usually considered mutually exclusive, with partially separated neural underpinnings. However, there is accumulating evidence that challenges this distinction between fear and anxiety, and simultaneous activation of fear and anxiety networks has been reported. Therefore, the current study experimentally tested potential interactions between fear and anxiety. Fifty-two healthy participants completed a differential fear conditioning paradigm followed by a test phase in which the conditioned stimuli were presented in front of threatening or neutral contextual images. To capture defense system activation, we recorded subjective (threat, US-expectancy), physiological (skin conductance, heart rate) and visuocortical (steady-state visual evoked potentials) responses to the conditioned stimuli as a function of contextual threat. Results demonstrated successful fear conditioning in all measures. In addition, threat and US-expectancy ratings, cardiac deceleration, and visuocortical activity were enhanced for fear cues presented in threatening compared with neutral contexts. These results are in line with an additive or interactive rather than an exclusive model of fear and anxiety, indicating facilitated defensive behavior to imminent danger in situations of potential threat.

Co-occurring Stress Trajectories and the Longitudinal Coupling of Internalizing Symptoms in Parent-Adolescent Dyads

Stress is one candidate mechanism posited to contribute to the intergenerational risk of psychopathology. However, the ways in which parent and child stress are related across adolescence, and the role that co-occurring parent and child stress may exert regarding bidirectional risk for internalizing symptoms, are not well understood. Using repeated measures data spanning 3-years, this study investigated (1) the extent to which trajectories of parent and child stress are related during adolescence, and (2) whether co-occurring parent and child stress trajectories mediate prospective, bidirectional associations between parent depression symptoms and child internalizing symptoms (depression, physical and social anxiety). Participants included 618 parent-adolescent dyads (age 8-16; 57% girls; 89% mothers). Parent depressive symptoms and child symptoms of depression, social anxiety, and physical anxiety were assessed via self-report questionnaire at baseline and 36 months later. Parent and child stress were assessed via self-report questionnaire every three months between 3- and 33-months (11 total assessments). Latent growth curve model (LGCM) analysis found that parent and child stress trajectories were positively related across development. Prospective LGCM mediation analysis showed that higher youth stress at 3-months partially mediated prospective relations between parental depressive symptoms at baseline and youth depressive, as well as physical and social anxiety symptoms at 36-months. Parent and child stress reinforce each other across adolescence and may lead to increased risk for psychopathology. Increases in child stress represent an important factor conferring transdiagnostic risk for internalizing among children of depressed parents.

Bed nuclei of the stria terminalis: A key hub in the modulation of anxiety

The bed nuclei of the stria terminalis (BST) is recognised as a pivotal integrative centre for monitoring emotional valence. It is implicated in the regulation of diverse affective states and motivated behaviours, and decades of research have firmly established its critical role in anxiety-related behavioural processes. Researchers have recently intricately dissected the BST's dynamic activities, its connection patterns and its functions with respect to specific cell types using multiple techniques such as optogenetics, in vivo calcium imaging and transgenic tools to unmask the complex circuitry mechanisms that underlie anxiety. In this review, we principally focus on studies of anxiety-involved neuromodulators within the BST and provide a comprehensive architecture of the anxiety network-highlighting the BST as a key hub in orchestrating anxiety-like behaviour. We posit that these promising efforts will contribute to the identification of an accurate roadmap for future treatment of anxiety disorders.

Functional connectivity strength and topology differences in social phobia adolescents with and without ADHD comorbidity

Social phobia (SP) is associated with changes in functional connectivity strength and topology. However, reported changes have been heterogeneous due to small sample sizes, inconsistent methodologies, and comorbidities, such as attention-deficit/hyperactivity disorder (ADHD), which has a high comorbidity rate with SP. Furthermore, there are few studies looking at SP in an adolescent population, a critical period for the development of the social brain. This project focuses on functional connectivity strength and topological differences in social phobia patients with and without ADHD comorbidity. We examined resting-state functional MRI images from 158 subjects, including 36 SP participants without ADHD comorbidity, 60 SP participants with ADHD comorbidity, and 62 healthy controls, with an overall average age of 14.16. We used a data-driven approach to examine impaired functional connectivity in a whole-brain analysis and higher-order topological differences in functional brain networks. We identified changes in the cerebellum and default mode network in social phobia patients as a whole, with the presence of ADHD comorbidity affecting various subsystems of the default mode network. Social phobia functional connectivity networks resembled random graphs, and local connectivity patterns in the superior occipital gyrus were different due to ADHD comorbidity. These alterations may indicate impairments in self-related processing, imagery, mentalizing, and predictive processes. We then used these changes in a linear support vector machine to distinguish between each pair of groups and achieved prediction accuracy significantly above chance rates. Our study extends prior research by showing that functional connectivity changes exist at adolescence, which are affected by ADHD comorbidity. As such, these results offer a new perspective in examining neurobiological changes in SP patients.

Neural responding during uncertain threat anticipation in pediatric anxiety

Excessive fear responses to uncertain threat are a key feature of anxiety disorders (ADs), though most mechanistic work considers adults. As ADs onset in childhood and confer risk for later psychopathology, we sought to identify conditions of uncertain threat that distinguish 8-17-year-old youth with AD (n = 19) from those without AD (n = 33), and assess test-retest reliability of such responses in a companion sample of healthy adults across three sites (n = 19). In an adapted uncertainty of threat paradigm, visual cues parametrically signaled threat of aversive stimuli (fear faces) in 25 % increments (0 %, 25 %, 50 %, 100 %), while participants underwent functional magnetic resonance imaging (fMRI). We compared neural response elicited by cues signaling different degrees of probability regarding the subsequent delivery of fear faces. Overall, youth displayed greater engagement of bilateral inferior parietal cortex, fusiform gyrus, and lingual gyrus during uncertain threat anticipation in general. Relative to healthy youth, AD youth exhibited greater activation in ventrolateral prefrontal cortex (vlPFC)/BA47 during uncertain threat anticipation in general. Further, AD differed from healthy youth in scaling of ventral striatum/sgACC activation with threat probability and attenuated flexibility of responding during parametric uncertain threat. Complementing these results, significant, albeit modest, cross-site test-retest reliability in these regions was observed in an independent sample of healthy adults. While preliminary due to a small sample size, these findings suggest that during uncertainty of threat, AD youth engage vlPFC regions known to be involved in fear regulation, response inhibition, and cognitive control. Findings highlight the potential of isolating neural correlates of threat anticipation to guide treatment development and translational work in youth.

Threat effects on attention networks in individuals with a history of externalizing behaviors

Research identifying the biobehavioral processes that link threat exposure to cognitive alterations can inform treatments designed to reduce perpetration of stress-induced aggression. The present study attempted to specify the effects of relatively predictable versus unpredictable threat on two attention networks, attentional alerting and executive control. In a sample of adults (n = 74, 35 % identifying as women, Mage = 32.85) with high rates of externalizing behaviors (e.g., substance use, criminal/legal system involvement, aggressivity), we measured event-related brain activity during an attention network test that manipulated cognitive systems activation under relatively unpredictable and predictable threat conditions. Results showed that threat exposure alters attentional alerting and executive control. The predictable threat condition, relative to unpredictable threat, increased visual alerting (N1 amplitude to alert vs. no alert cue conditions) and decreased attention to the task (P3 amplitude to subsequent task-relevant flankers, but these effects did not survive adjusting for multiple tests. In contrast, overall threat and unpredictable threat conditions were associated with faster response time to alert cue (versus no cue) and poorer conflict processing, operationalized as flanker N2 reductions and slower response time to incongruent (versus congruent) flanker trials. These results expand what is known about threat-related modulation of cognition in a sample of individuals with histories of externalizing behaviors.

'Feeling' or 'sensing' the future? Testing for anomalous cognitions in clinical versus healthy populations

In the study and treatment of psychosis, emotional intelligence (EI) and thinking styles are important patient characteristics for successful outcomes in clinical intervention. Anticipation of unpredictable stimuli (AUS) may be understood as an anomalous perception and anomalous cognition in which an individual supposedly senses and recognizes future stimuli in an unexpected way, also referred to as “hunches or premonitions.” This examined the roles of EI and thinking styles in AUSs in convenience samples of healthy participants (n = 237) versus patients diagnosed with psychosis (n = 118). We adjusted several quadratic and exponential regression models according to the obtained functions. Group means were also compared to examine differences in EI scores for participants with psychosis compared to healthy participants. In the healthy group, EI predicted AUSs with a weight between 42% and 58%. Thinking styles were not correlated with AUSs. However, EI was not correlated with AUSs in the clinical group. Patients with psychosis tended to score higher on AUSs and lower on EI and thinking styles compared to participants in the healthy group. We discuss EI as a variable that can contextualize some anomalous perceptions which are otherwise difficult to classify or measure within the classic psychosis continuum model.

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.

A Research Domain Criteria (RDoC)-Guided Dashboard to Review Psilocybin Target Domains: A Systematic Review

BACKGROUND

Preliminary results from randomized controlled studies as well as identified molecular, cellular, and circuit targets of select psychedelics (e.g., psilocybin) suggest that their effects are transdiagnostic. In this review, we exploit the Research Domain Criteria (RDoC) transdiagnostic framework, to synthesize extant literature on psilocybin.

OBJECTIVE

We aimed to identify RDoC-based effects of psilocybin and vistas for future mechanistic and interventional research.

METHODS

A systematic search in electronic databases (i.e., PubMed, Scopus, PsycINFO, and Web of Science) performed in January and February 2021 identified English articles published between 1990 and 2020 reporting the effects of psilocybin on mental health measures. Data from included articles were retrieved and organized according to the RDoC bio-behavioral matrix and its constituent six main domains, namely: positive valence systems, negative valence systems, cognitive systems, social processes, sensorimotor systems, and arousal and regulatory systems.

RESULTS

The preponderance of research with psilocybin has differentially reported beneficial effects on positive valence systems, negative valence system, and social process domains. The data from the included studies support both short-term (23 assessments) and long-term (15 assessments) beneficial effects of psilocybin on the positive valence systems. While 12 of the extracted outcome measures suggest that psilocybin use is associated with increases in the "fear" construct of the negative valence systems domain, 19 findings show no significant effects on this construct, and seven parameters show lowered levels of the "sustained threat" construct in the long term. Thirty-four outcome measures revealed short-term alterations in the social systems' construct namely, "perception and understanding of self," and "social communications" as well as enhancements in "perception and understanding of others" and "affiliation and attachment". The majority of findings related to the cognitive systems' domain reported dyscognitive effects. There have been relatively few studies reporting outcomes of psilocybin on the remaining RDoC domains. Moreover, seven of the included studies suggest the transdiagnostic effects of psilocybin. The dashboard characterization of RDoC outcomes with psilocybin suggests beneficial effects in the measures of reward, threat, and arousal, as well as general social systems.

CONCLUSIONS

Psilocybin possesses a multi-domain effectiveness. The field would benefit from highly rigorous proof-of-mechanism research to assess the effects of psilocybin using the RDoC framework. The combined effect of psilocybin with psychosocial interventions with RDoC-based outcomes is a priority therapeutic vista.

Alcohol's effects during uncertain and uncontrollable stressors in the laboratory

Alcohol's effects on reactivity to stressors depends on the nature of the stressor and the reactivity being assessed. Research identifying characteristics of stressors that modulate reactivity and clarifies the neurobehavioral, cognitive, and affective components of this reactivity may help prevent, reduce or treat the negative impacts of acute and chronic alcohol use with implications for other psychopathology involving maladaptive reactivity to stressors. We used a novel, multi-measure, cued electric shock stressor paradigm in a greater university community sample of adult recreational drinkers to test how alcohol (N=64), compared to No-alcohol (N=64), effects reactivity to stressors that vary in both their perceived certainty and controllability. Preregistered analyses suggested alcohol significantly dampened subjective anxiety (self-report) and defensive reactivity (startle potentiation) more during uncertain than during certain stressors regardless of controllability, suggesting that stressor uncertainty -but not uncontrollability- may be sufficient to enhance alcohol's stress reactivity dampening and thus negative reinforcement potential.

Intolerance of uncertainty and psychophysiological reactivity in anticipation of unpredictable threat in youth

OBJECTIVE

Intolerance of uncertainty (IU) is a key transdiagnostic feature of internalizing psychopathology. An increasing body of research suggests that IU is associated with increased psychophysiological reactivity in anticipation of unpredictable threat. However, most studies examining the psychophysiological correlates of IU have been conducted in adults. There is a critical need to understand the relationship between IU and psychophysiological reactivity in anticipation of unpredictable threat during adolescence, a key developmental period associated with increased exploration of situations with uncertain outcomes. Thus, the present study examined the association between (1) youth IU and (2) parental IU (as an indicator of risk) in relation to youth defensive motivation (startle reflex) and attention (startle probe N100 and P300) in anticipation of unpredictable threat.

METHODS

The sample included 193 13 to 22-year-old (M = 17.33, SD = 1.97) females and a biological parent. Participants and their parent completed a self-report measure of prospective and inhibitory IU. Youth startle potentiation, probe N100 enhancement, and probe P300 suppression (indicating increased attention to threat) were measured in anticipation of predictable and unpredictable threat.

RESULTS

Youth prospective IU and inhibitory IU were not related to youth psychophysiological reactivity to predictable or unpredictable threat. Greater parental prospective IU was associated with greater youth startle potentiation and probe N100 enhancement in anticipation of unpredictable threat.

CONCLUSION

The present study suggests that parental IU, but not concurrent IU, is associated with heightened defensive motivation and attentional engagement in anticipation of unpredictable threat in youth.

Freezing revisited: coordinated autonomic and central optimization of threat coping

Animals have sophisticated mechanisms for coping with danger. Freezing is a unique state that, upon threat detection, allows evidence to be gathered, response possibilities to be previsioned and preparations to be made for worst-case fight or flight. We propose that - rather than reflecting a passive fear state - the particular somatic and cognitive characteristics of freezing help to conceal overt responses, while optimizing sensory processing and action preparation. Critical for these functions are the neurotransmitters noradrenaline and acetylcholine, which modulate neural information processing and also control the sympathetic and parasympathetic branches of the autonomic nervous system. However, the interactions between autonomic systems and the brain during freezing, and the way in which they jointly coordinate responses, remain incompletely explored. We review the joint actions of these systems and offer a novel computational framework to describe their temporally harmonized integration. This reconceptualization of freezing has implications for its role in decision-making under threat and for psychopathology.

Aversive response to uncertainty as a mediator for the effect of a mindfulness intervention on symptoms of anxiety

THEORETICAL BACKGROUND

Intolerance of uncertainty plays a central role in anxiety and research suggests that it's an important treatment target. Investigating response to uncertainty using other dimensions than self-report, such as physiological responses, can further the effort to understand the role of uncertainty in anxiety more fully. Mindfulness interventions have become increasingly interesting in their application to anxiety, as they foster acceptance of unpleasant aspects of experience. The aims of the study were to examine whether a mindfulness intervention reduced response to uncertainty and anxiety symptoms, and to examine the associations between intolerance of uncertainty, physiological response to uncertainty, mindfulness and anxiety.

METHODS

Participants were 117 students who completed a two-week mindfulness or audiobook control intervention. At pre- and post-intervention assessments, measures of anxiety, mindfulness, and intolerance of uncertainty were completed and a threat-of-shock task assessing startle responding to unpredictable shock was administered.

RESULTS

Findings showed a significant effect of the intervention for social anxiety symptoms. Furthermore, intolerance of uncertainty mediated the effect of the intervention on symptoms for social anxiety and worry. No such effects were found for physiological response to uncertainty.

CONCLUSION

The study adds to the understanding of the role of response to uncertainty in anxiety as well as to its mechanistic role in the context of mindfulness practice. Implications and possible explanations for the non-significant main effects of the intervention on anxiety symptoms and physiological response to uncertainty are discussed.

Uncertain in the face of change: Lack of contingency shift awareness during extinction is associated with higher fear-potentiated startle and PTSD symptoms in children

Intolerance of uncertainty is a transdiagnostic risk factor for fear-related disorders and is associated with higher levels of anxiety in children and adolescents. It is unclear how uncertainty relates to development of psychopathology in children who have experienced trauma in early life. The present study used a fear-potentiated startle paradigm in children to examine associations between uncertainty (assessed as unawareness of a change in reinforcement during fear extinction) and symptoms of anxiety and posttraumatic stress disorder (PTSD), as well as startle potentiation to threat and safety cues. Results showed that unaware children had strong positive associations between trauma exposure and PTSD symptoms, whereas aware children did not. Uncertainty interacted with anxiety in that children who were both unaware and had higher anxiety displayed higher fear-potentiated startle to safety cues and did not show discrimination between threat and safety during fear conditioning. These results suggest that anxious children who persist in associating a threat cue with an aversive event during extinction, after repeated presentations of the no longer reinforced conditioned stimulus, may express psychophysiological phenotypes related to PTSD.

Association between startle reactivity to uncertain threats and structural brain volume

Sensitivity to uncertain threat (U-threat) is a clinically important individual difference factor in multiple psychopathologies. Recent studies have implicated a specific frontolimbic circuit as a key network involved in the anticipation of aversive stimuli. In particular, the insula, thalamus, and dorsal anterior cingulate cortex (dACC) have recently been found to be robustly activated by anticipation of U-threat. However, no study to date has examined the association between U-threat reactivity and structural brain volume. In the present study, we utilized a pooled sample of 186 young adult volunteers who completed a structural MRI scan and the well-validated No-Predictable-Unpredictable (NPU) threat of electric shock task. Startle eyeblink potentiation was collected during the NPU task as an objective index of aversive reactivity. ROI-based analyses revealed that increased startle reactivity to U-threat was associated with reduced gray matter volume in the right insula and bilateral thalamus, but not the dACC. These results add to a growing literature implicating the insula and thalamus as core nodes involved in individual differences in U-threat reactivity.

Anxiety and initial value dependence in startle habituation

Studies suggest that deficits in startle reflex habituation occur in trait and clinical anxiety. Measures of habituation are affected by the magnitude of the initial response, with larger initial responses predicting a steeper decline in response over repeated trials. This relationship between initial value and change, commonly called the Law of Initial Value or initial value dependence (IVD), has been partialled out as a covariate in habituation research, but variation in IVD may be informative in itself, reflecting differences in physiological reactivity. The present study explored how trait anxiety and contextual anxiety relate to habituation kinetics of the startle eyeblink response: initial value, linear habituation slope, and the relationship between them (IVD). Participants (n = 31; 15 Control, 16 Contextual Anxiety [CA]) were exposed to two blocks of acoustic startle stimuli, and CA participants were warned that they may receive an electrical shock to the wrist during block 2. Trait anxiety did not predict habituation slope, but it did predict a weaker IVD relationship, meaning that high initial startle magnitude was less predictive of a steep response decline in trait‐anxious subjects. Meanwhile, CA did not impact startle habituation or IVD. The results suggest that individual differences in trait anxiety are related to the relationship between initial physiological response magnitude and subsequent change in response. IVD in startle habituation may thus serve as a better biomarker of healthy emotional responding than startle habituation per se.

Startle reflex habituation relates to emotion regulation, but this relationship may be more meaningful when habituation is considered in the context of initial reactivity, referred to as initial value dependence (IVD). IVD is related to trait anxiety, and may also predict the efficacy of emotion regulation more generally.

When the approaching threat is uncertain: Dynamics of defensive motivation and attention in trait anxiety

Uncertainty of threat has been linked to anxiety, but little is known about how neurophysiological responses change as uncertain threats approach and whether trait anxiety modulates these changes. The current study was designed to explore aspects of the dynamics of defensive motivation (startle reflex elicited by acoustic startle probes), attention (probe N100 component of event-related potentials elicited by acoustic startle probes), and autonomic nervous system activity (heart rate) when the approaching threat was certain or uncertain in a variant of the threat probability task. Behavioral results showed that high-trait anxious individuals reported higher levels of anxiety than low-trait anxious individuals only under the uncertain threat condition. Electromyographic data showed that high-trait anxious individuals tended to produce a more pronounced startle reflex, especially when the uncertain threat was proximal. This pattern was not observed in low-trait anxious individuals. By examining early attention engagement through probe N100, we observed a similar pattern in relation to defensive motivation. Moreover, under the uncertain threat condition, high-trait anxious individuals yielded a greater deceleration of heart rate than low-trait anxious individuals. These results indicate a distinct modulation effect of trait anxiety in the dynamics of defensive motivation, attention, and the autonomic nervous system during the anticipation of uncertain threats.

Sustained threat and phasic fear in the laboratory and cognitive-emotional processes of anxiety in everyday life - An ambulatory assessment study

Fear is a phasic state of apprehension to an imminent threat, whereas anxiety is a more sustained state of expecting a potential threat leading to tension and worry. The NPU-threat test is a laboratory startle paradigm allowing a reliable and valid assessment of both, fear- and anxiety-potentiated reactions. It is suggested to differentiate between anxiety disorders, but little is known on associations with everyday life experiences of cognitive-emotional processes regarding anxiety in non-clinical samples. In the present project, the NPU-threat test was applied in three studies with (1) unselected healthy individuals, (2) participants with extreme manifestations of trait anxiety (low vs. high) and (3) individuals preparing for a high-stakes exam. Self-reported states of emotionality and worry were assessed during a four-day ambulatory assessment (AA). Overall, NPU-threat test measures did not significantly differ between studies, while the AA dependent measures were sufficiently sensitive to capture differences between groups. However, there was no significant association between psychophysiological measures of the NPU-threat test and AA state measures across participants. In participants recruited for low vs. high trait anxiety we found an association with AA worry and emotionality, but no interaction with potentiated startle. The present findings do not support the idea of a link between our laboratory biomarker and adaptive regulation of cognitive-emotional states in everyday life in healthy individuals. We speculate that an association between laboratory physiological measures and everyday experience of anxious states may be detectable in clinical samples.

Event-related potentials to acoustic startle probes during unpredictable threat are associated with individual differences in intolerance of uncertainty

Individual differences in sensitivity to unpredictable threat may be a critical mechanism for internalizing psychopathology phenotypes. The present study examined whether the startle probe-elicited N100 and P300 during unpredictable threat - two event-related potentials indexing early and elaborative attentional processing of unpredictable threat - may be endophenotypes for internalizing psychopathology, including fear and distress/misery disorders and intolerance of uncertainty (IU), a clinical trait that is transdiagnostically associated with internalizing disorders. A large sample of adult siblings (N = 375) completed the no, predictable, and unpredictable threat task, during which the N100 and P300 were recorded. Relative to the no threat condition, N100 was more strongly enhanced in anticipation of unpredictable than predictable threat while P300 was suppressed to both predictable and unpredictable threat. While neither N100 enhancement nor P300 suppression to unpredictable threat was associated with fear or distress/misery disorders, they were negatively linked to inhibitory IU (a facet of IU). Thus, individuals high in inhibitory IU showed reduced attentional engagement with the threatening context when it was unpredictable. Further, N100 enhancement and, to a lesser degree, P300 suppression to unpredictable threat showed familial aggregation - a key criterion for determining whether a biomarker is an endophenotype. In sum, N100 enhancement and P300 suppression to unpredictable threat may be endophenotypes for dimensional measures of internalizing psychopathology.

Differential effects of the translocator protein 18 kDa (TSPO) ligand etifoxine and the benzodiazepine alprazolam on startle response to predictable threat in a NPU-threat task after acute and short-term treatment

RATIONALE

Benzodiazepines have been extensively investigated in experimental settings especially after single administration, which mostly revealed effects on unpredictable threat (U-threat) rather than predictable threat (P-threat). Given the need for pharmacological alternatives with a preferable side-effect profile and to better represent clinical conditions, research should cover also other anxiolytics and longer application times.

OBJECTIVES

The present study compared the acute and short-term effects of the translocator protein 18 kDa (TSPO) ligand etifoxine and the benzodiazepine alprazolam on P-threat and U-threat while controlling for sedation.

METHODS

Sixty healthy male volunteers, aged between 18 and 55 years, were randomly assigned to receive a daily dose of either 150 mg etifoxine, 1.5 mg alprazolam, or placebo for 5 days. On days 1 and 5 of intake, they performed a NPU-threat task including neutral (N), predictable (P), and unpredictable (U) conditions, while startle responsivity and self-reports were studied. Sedative effects were assessed using a continuous performance test.

RESULTS

Neither alprazolam nor etifoxine affected startle responsivity to U-threat on any of the testing days. While etifoxine reduced the startle response to P-threat on day 1 of treatment for transformed data, a contrary effect of alprazolam was found for raw values. No effects on self-reports and no evidence of sedation could be observed for either drug.

CONCLUSIONS

None of the anxiolytic substances had an impact on startle potentiation to U-threat even after several days of intake. The effects of the anxiolytics on startle responsivity to P-threat as well as implications for future studies are discussed.

Cross-species anxiety tests in psychiatry: pitfalls and promises

Behavioural anxiety tests in non-human animals are used for anxiolytic drug discovery, and to investigate the neurobiology of threat avoidance. Over the past decade, several of them were translated to humans with three clinically relevant goals: to assess potential efficacy of candidate treatments in healthy humans; to develop diagnostic tests or biomarkers; and to elucidate the pathophysiology of anxiety disorders. In this review, we scrutinise these promises and compare seven anxiety tests that are validated across species: five approach-avoidance conflict tests, unpredictable shock anticipation, and the social intrusion test in children. Regarding the first goal, three tests appear suitable for anxiolytic drug screening in humans. However, they have not become part of the drug development pipeline and achieving this may require independent confirmation of predictive validity and cost-effectiveness. Secondly, two tests have shown potential to measure clinically relevant individual differences, but their psychometric properties, predictive value, and clinical applicability need to be clarified. Finally, cross-species research has not yet revealed new evidence that the physiology of healthy human behaviour in anxiety tests relates to the physiology of anxiety symptoms in patients. To summarise, cross-species anxiety tests could be rendered useful for drug screening and for development of diagnostic instruments. Using these tests for aetiology research in healthy humans or animals needs to be queried and may turn out to be unrealistic.

Ethnic differences in behavioral and physiological indicators of sensitivity to threat

The clinical presentation of anxiety may differ between Hispanics/Latinx (H/L) and non-H/L, although findings on ethnic differences in self-reported anxiety symptoms have been mixed. Fewer studies have focused on ethnic differences in quick and relatively automatic laboratory-assessed indicators of anxiety symptoms, which have the potential to be more objective indicators than self-report. Therefore, the present study examined ethnic differences in two laboratory-assessed indicators of threat sensitivity (an important transdiagnostic mechanism of anxiety): attentional bias to threat and electromyography startle reactivity to threat. White H/L (n = 117) and White non-H/L (n = 168) adults who were matched on demographics and lifetime psychopathology (including anxiety) completed a dot-probe task to assess attentional bias to threat and the No-Predictable-Unpredictable threat (NPU) task to assess startle reactivity to threat. Results indicated that H/L displayed less Slow OrientationRB (β = -0.27, p = 0.032, R2β∗ = 0.02), and increased Slow DisengagementRB (β = 0.31, p = 0.016, R2β∗ = 0.02) compared to non-H/L. H/L exhibited blunted overall startle compared to non-H/L (β = -0.30, p = 0.014, R2β∗ = 0.02), but groups did not differ in startle reactivity to either predictable or unpredictable threat. In summary, H/L and non-H/L may differ in their experience and presentation of anxiety symptoms and such differences may vary across indicators of sensitivity to threat.

Intolerance of uncertainty and physiological responses during instructed uncertain threat: A multi-lab investigation

Individuals with high self-reported Intolerance of uncertainty (IU) tend to interpret uncertainty negatively. Recent research has been inconclusive on evidence of an association between IU and physiological responses during instructed uncertain threat. To address this gap, we conducted secondary analyses of IU and physiology data recorded during instructed uncertain threat tasks from two lab sites (Wisconsin-Madison; n = 128; Yale, n = 95). No IU-related effects were observed for orbicularis oculi activity (auditory startle-reflex). Higher IU was associated with: (1) greater corrugator supercilii activity to predictable and unpredictable threat of shock, compared to the safety from shock, and (2) poorer discriminatory skin conductance response between the unpredictable threat of shock, relative to the safety from shock. These findings suggest that IU-related biases may be captured differently depending on the physiological measure during instructed uncertain threat. Implications of these findings for neurobiological models of uncertainty and anticipation in anxiety are discussed.

Predictive waves in the autism-schizophrenia continuum: A novel biobehavioral model

The brain is a predictive machine. Converging data suggests a diametric predictive strategy from autism spectrum disorders (ASD) to schizophrenic spectrum disorders (SSD). Whereas perceptual inference in ASD is rigidly shaped by incoming sensory information, the SSD population is prone to overestimate the precision of their priors' models. Growing evidence considers brain oscillations pivotal biomarkers to understand how top-down predictions integrate bottom-up input. Starting from the conceptualization of ASD and SSD as oscillopathies, we introduce an integrated perspective that ascribes the maladjustments of the predictive mechanism to dysregulation of neural synchronization. According to this proposal, disturbances in the oscillatory profile do not allow the appropriate trade-off between descending predictive signal, overweighted in SSD, and ascending prediction errors, overweighted in ASD. These opposing imbalances both result in an ill-adapted reaction to external challenges. This approach offers a neuro-computational model capable of linking predictive coding theories with electrophysiological findings, aiming to increase knowledge on the neuronal foundations of the two spectra features and stimulate hypothesis-driven rehabilitation/research perspectives.

Facing successfully high mental workload and stressors: An fMRI study

The present fMRI study aimed at highlighting patterns of brain activations and autonomic activity when confronted with high mental workload and the threat of auditory stressors. Twenty participants performed a complex cognitive task in either safe or aversive conditions. Our results showed that increased mental workload induced recruitment of the lateral frontoparietal executive control network (ECN), along with disengagement of medial prefrontal and posterior cingulate regions of the default mode network (DMN). Mental workload also elicited an increase in heart rate and pupil diameter. Task performance did not decrease under the threat of stressors, most likely due to efficient inhibition of auditory regions, as reflected by a large decrement of activity in the superior temporal gyri. The threat of stressors was also accompanied with deactivations of limbic regions of the salience network (SN), possibly reflecting emotional regulation mechanisms through control from dorsal medial prefrontal and parietal regions, as indicated by functional connectivity analyses. Meanwhile, the threat of stressors induced enhanced ECN activity, likely for improved attentional and cognitive processes toward the task, as suggested by increased lateral prefrontal and parietal activations. These fMRI results suggest that measuring the balance between ECN, SN, and DMN recruitment could be used for objective mental state assessment. In this sense, an extra recruitment of task‐related regions and a high ratio of lateral versus medial prefrontal activity may represent a relevant marker of increased but efficient mental effort, while the opposite may indicate a disengagement from the task due to mental overload and/or stressors.

Defensive Mobilization During Anticipation of Symptom Provocation: Association With Panic Pathology

BACKGROUND

Anxious apprehension about feared body symptoms is thought to play a crucial role in the development, chronicity, and treatment of panic disorder (PD). In this study, we therefore aimed to elucidate the role of defensive reactivity to anticipated unpleasant symptoms in PD that can contribute to a better understanding of pathomechanisms of PD as well as identification of potential targets in PD-focused interventions. By measuring amygdala-dependent potentiation of the startle reflex, we aimed to investigate whether 1) patients with PD exhibit a specifically increased defensive reactivity to anticipated unpleasant body symptoms and 2) whether clinical severity of panic symptomatology varies with magnitude of defensive activation.

METHODS

Defensive mobilization to anticipated threat was investigated in 73 patients with a primary diagnosis of PD with agoraphobia (PDA) and 52 healthy control subjects. Threat of symptom provocation was established by a standardized hyperventilation task and contrasted to threat of shock to the forearm of the participant.

RESULTS

Patients with PDA and healthy control subjects did not differ in their defensive responses during anticipation of shock. In contrast, patients with severe PDA as compared with healthy control subjects exhibited increased defensive response mobilization and reported more anxiety and panic symptoms during anticipation of feared body symptoms. Moreover, startle potentiation during anticipation of hyperventilation covaried with the severity of panic symptomatology.

CONCLUSIONS

The present findings suggest that increased defensive mobilization during anticipation of body symptoms is a neurobiological correlate of severe PDA that should be specifically targeted in PD interventions and might be used to monitor treatment success.

Fear of the unknown as a mechanism of the inverse relation between life meaning and psychological distress

BACKGROUND AND OBJECTIVES

Although there is accumulating evidence for an inverse relation between life meaning and psychological distress, little is known about the mechanisms of this relation. Using cross-sectional, observational methods, this research examined fear of uncertainty as one potential mechanism.

DESIGN AND METHODS

Study 1 (N = 141) was completed with a convenience sample, a unidimensional measure of life meaning, and general measures of anxiety and depression. Study 2 (N = 152) was completed with a sample prescreened for anxiety, a multidimensional measure of life meaning, and clinical measures of anxiety and depression.

RESULTS

The results from both studies generally showed an inverse relation between life meaning and psychological distress. Study 2 further indicated that these relations were stronger for the meaning subscale of perceiving life as coherent/comprehensible than the subscales assessing whether participants' lives are perceived as purposeful or significant. Mediation analyses in both studies showed indirect effects of life meaning on psychological distress through fear of uncertainty.

CONCLUSIONS

These findings support and extend previous research by showing that (i) meaning-as-comprehension may be particularly important in regards to psychological distress, and (ii) fear of uncertainty may mediate the inverse relation between meaning and measures of anxiety and depression.

Preventing adolescent synaptic pruning in mouse prelimbic cortex via local knockdown of α4βδ GABAA receptors increases anxiety response in adulthood

Anxiety is increasingly reported, especially in adolescent females. The etiology is largely unknown, which limits effective treatment. Layer 5 prelimbic cortex (L5PL) increases anxiety responses but undergoes adolescent synaptic pruning, raising the question of the impact of pruning on anxiety. Here we show that preventing L5PL pruning increases anxiety in response to an aversive event in adolescent and adult female mice. Spine density of Golgi-stained neurons decreased ~ 63% from puberty (~ PND35, vaginal opening) to post-puberty (PND56, P < 0.0001). Expression of α4βδ GABA_A receptors (GABARs) transiently increased tenfold in L5PL at puberty (P < 0.00001), but decreased post-pubertally. Both global and local knockdown of these receptors during puberty prevented pruning, increasing spine density post-pubertally (P < 0.0001), an effect reversed by blocking NMDA receptors (NMDARs). Pubertal expression of the NMDAR-dependent spine protein kalirin7 decreased (50%, P < 0.0001), an effect prevented by α4 knock-out, suggesting that α4βδ-induced reductions in kalirin7 underlie pruning. Increased spine density due to local α4 knockdown at puberty decreased open arm time on the elevated plus maze post-pubertally (62%, P < 0.0001) in response to an aversive stimulus, suggesting that increases in L5PL synapses increase anxiety responses. These findings suggest that prelimbic synaptic pruning is necessary to limit anxiety in adulthood and may suggest novel therapies.

Hold your breath: Voluntary breath-holding time predicts defensive activation to approaching internal threat

Bodily disturbances, like dyspnea, elicit responses to regain homeostasis and ensure survival. However, this life-saving function can become hyperreactive, which may lead to the emergence of psychopathology. This study investigated whether maximal voluntary breath-holding time (mvBHT), a biobehavioral marker that characterizes sensitivity to respiratory stimulation, predicts defensive mobilization to cues signaling the proximity of a mild electric shock vs. a respiratory threat (shortness of breath elicited by forced breath-holding) and the opportunity to avoid threat delivery in 60 healthy participants. While the startle reflex, a measure of defensive mobilization, generally increased with the proximity of an inevitable threat, shorter breath-holding time was specifically associated with greater startle potentiation when anticipating a respiratory threat but not an electric shock. In contrast, when both threats were avoidable, the startle reflex was comparably inhibited, irrespective of mvBHT. This study suggests that mvBHT specifically predicts hypersensitive responding to an anticipated inevitable respiratory threat.