Instructions and experiential learning have similar impacts on pain and pain-related brain responses but produce dissociations in value-based reversal learning

Recent data suggest that interactions between systems involved in higher order knowledge and associative learning drive responses during value-based learning. However, it is unknown how these systems impact subjective responses, such as pain. We tested how instructions and reversal learning influence pain and pain-evoked brain activation. Healthy volunteers (n=40) were either instructed about contingencies between cues and aversive outcomes or learned through experience in a paradigm where contingencies reversed three times. We measured predictive cue effects on pain and heat-evoked brain responses using functional magnetic resonance imaging. Predictive cues dynamically modulated pain perception as contingencies changed, regardless of whether participants received contingency instructions. Heat-evoked responses in the insula, anterior cingulate, and other regions updated as contingencies changed, and responses in the prefrontal cortex mediated dynamic cue effects on pain, whereas responses in the brainstem’s rostroventral medulla (RVM) were shaped by initial contingencies throughout the task. Quantitative modeling revealed that expected value was shaped purely by instructions in the Instructed Group, whereas expected value updated dynamically in the Uninstructed Group as a function of error-based learning. These differences were accompanied by dissociations in the neural correlates of value-based learning in the rostral anterior cingulate, thalamus, and posterior insula, among other regions. These results show how predictions dynamically impact subjective pain. Moreover, imaging data delineate three types of networks involved in pain generation and value-based learning: those that respond to initial contingencies, those that update dynamically during feedback-driven learning as contingencies change, and those that are sensitive to instruction. Together, these findings provide multiple points of entry for therapies designs to impact pain.

Which Anxious Adolescents Were Most Affected by the COVID-19 Pandemic?

Although the COVID-19 pandemic caused significant stress and anxiety among many, individuals' experiences varied. We examined if specific forms of anxiety predicted distinct trajectories of anxiety, perceived stress, and COVID-related worries during three early months of the pandemic. In a longitudinal study (N = 291), adolescents' (n = 194) social and generalized anxiety levels were assessed via parent- and self-reports and clinical diagnostic interviews. In young adulthood (n = 164), anxiety, stress, and COVID-related worries were assessed thrice during the pandemic. Pre-pandemic generalized anxiety predicted higher initial levels and maintenance of anxiety, stress, and COVID-related worries during the pandemic. In contrast, pre-pandemic social anxiety predicted lower initial levels of anxiety, stress, and COVID-related worries, but this initial effect on anxiety and stress was offset over time by social anxiety's positive effect on the slope. Our results highlight the importance of understanding how pre-pandemic factors influence individuals' experiences during the pandemic.

Attentional biases in human anxiety

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

Test-Retest Reliability of an Adaptive Thermal Pain Calibration Procedure in Healthy Volunteers

Quantitative sensory testing (QST) allows researchers to evaluate associations between noxious stimuli and acute pain in clinical populations and healthy participants. Despite its widespread use, our understanding of QST’s reliability is limited, as reliability studies have used small samples and restricted time windows. We examined the reliability of pain ratings in response to noxious thermal stimulation in 171 healthy volunteers (n = 99 female, n = 72 male) who completed QST on multiple visits ranging from 1 day to 952 days between visits. On each visit, participants underwent an adaptive pain calibration in which they experienced 24 heat trials and rated pain intensity after stimulus offset on a 0 to 10 Visual Analog Scale. We used linear regression to determine pain threshold, pain tolerance, and the correlation between temperature and pain for each session and examined the reliability of these measures. Threshold and tolerance were moderately reliable (Intra-class correlation = .66 and .67, respectively; P < .001), whereas temperature-pain correlations had low reliability (Intra-class correlation = .23). In addition, pain tolerance was significantly more reliable in female participants than male participants, and we observed similar trends for other pain sensitive measures. Our findings indicate that threshold and tolerance are largely consistent across visits, whereas sensitivity to changes in temperature vary over time and may be influenced by contextual factors.

Structural Brain Correlates of Childhood Inhibited Temperament: An ENIGMA-Anxiety Mega-analysis

Temperament involves stable behavioral and emotional tendencies that differ between individuals, which can be first observed in infancy or early childhood and relate to behavior in many contexts and over many years.1 One of the most rigorously characterized temperament classifications relates to the tendency of individuals to avoid the unfamiliar and to withdraw from unfamiliar people, objects, and unexpected events. This temperament is referred to as behavioral inhibition or inhibited temperament (IT).2 IT is a moderately heritable trait1 that can be measured in multiple species.3 In humans, levels of IT can be quantified from the first year of life through direct behavioral observations or reports by caregivers or teachers. Similar approaches as well as self-report questionnaires on current and/or retrospective levels of IT1 can be used later in life.

Personalized attention control therapy for PTSD: effectiveness and moderators of outcome in a randomized controlled trial

BACKGROUND

Previous randomized controlled trials (RCTs) suggest that attention control therapy (ACT), targeting aberrant fluctuations of attention toward and away from threats in patients with PTSD, may be effective in reducing symptoms. The current RCT examined whether the use of personalized-trauma stimuli enhances ACT efficacy in patients with PTSD. Additional moderators of treatment outcome were tested on an exploratory basis.

METHODS

Sixty patients with PTSD were randomly assigned to either personalized ACT, non-personalized ACT, or a control condition. Changes in symptoms were examined across pre-treatment, post-treatment, and a 3-month follow-up. Attentional interference was examined pre- and post-treatment. Baseline clinical and cognitive indices as well as the time elapsed since the trauma were tested as potential moderators of treatment outcome.

RESULTS

A significant reduction in clinical symptoms was noted for all three conditions with no between-group differences. Attention bias variability decreased following ACT treatment. Personalized ACT was more effective relative to the control condition when less time had elapsed since the trauma. Baseline clinical and cognitive indices did not moderate treatment outcome.

CONCLUSIONS

In this RCT of patients with PTSD, ACT was no more effective in reducing PTSD symptoms than a control condition. The data also suggest a potential benefit of personalized ACT for patients who experienced their trauma more recently.

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

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

Development and validation of the Attention Bias Questionnaire (ABQ)

OBJECTIVES

Various psychopathologies are associated with threat-related attention biases, which are typically measured using mechanized behavioral tasks. While useful and objective, behavioral measures do not capture the subjective experience of biased attention in daily-living. To complement extant behavioral measures, we developed and validated a self-report measure of threat-related attention bias - the Attention Bias Questionnaire (ABQ).

METHODS

The ABQ consists of nine items reflecting the subjective experience of attention bias towards threats. To enable personalized relevance in threat-content, the general term "threat" was used, and respondents were instructed to refer to specific things that threaten them personally. In a set of five studies, the ABQ was developed and validated. Internal consistency, discriminant validity, test-retest reliability, and convergent validity were tested.

RESULTS

The ABQ emerged as a coherent and stable measure with two sub-scales: Engagement with Threat and Difficulty to Disengage from Threat. ABQ scores were positively correlated with trait anxiety, social anxiety, PTSD, and depression, as well as behaviorally measured attention bias.

CONCLUSION

Assessing the subjective experience of threat-related attention bias can enrich existing knowledge about the cognitive mechanisms underlying psychopathology and complement extant behavioral bias measures in research and clinical evaluation.

Computational modeling of threat learning reveals links with anxiety and neuroanatomy in humans

Influential theories implicate variations in the mechanisms supporting threat learning in the severity of anxiety symptoms. We use computational models of associative learning in conjunction with structural imaging to explicate links among the mechanisms underlying threat learning, their neuroanatomical substrates, and anxiety severity in humans. We recorded skin-conductance data during a threat-learning task from individuals with and without anxiety disorders (N=251; 8-50 years; 116 females). Reinforcement-learning model variants quantified processes hypothesized to relate to anxiety: threat conditioning, threat generalization, safety learning, and threat extinction. We identified the best-fitting models for these processes and tested associations among latent learning parameters, whole-brain anatomy, and anxiety severity. Results indicate that greater anxiety severity related specifically to slower safety learning and slower extinction of response to safe stimuli. Nucleus accumbens gray-matter volume moderated learning-anxiety associations. Using a modeling approach, we identify computational mechanisms linking threat learning and anxiety severity and their neuroanatomical substrates.

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.

A Developmental Pathway From Early Behavioral Inhibition to Young Adults' Anxiety During the COVID-19 Pandemic

Objective

The COVID-19 pandemic has brought unprecedented changes to young adults' lives, resulting in mental health difficulties for many; however, some individuals are particularly prone to heightened anxiety. Little is known about the early life predictors of anxiety during the pandemic. We examined a developmental pathway from behavioral inhibition (BI), a temperament characterized by fearful responses toward novelty, to changes in young adults' anxiety during the initial period of the pandemic. We hypothesized that a stable pattern of BI across early childhood would predict greater adolescent worry dysregulation, which in turn would predict increases in young adult anxiety during a stressful phase of the pandemic.

Method

Participants (N = 291; 54% female) were followed from toddlerhood to young adulthood. BI was observed at ages 2 and 3 years. Social wariness was observed at age 7 years. Participants rated their worry dysregulation in adolescence (age 15) and anxiety in young adulthood (age 18) at 2 assessments during the COVID-19 pandemic, 1 month apart.

Results

A significant moderated mediation, in which a stable pattern of BI from toddlerhood to childhood, as compared to the absence of this pattern, predicted greater worry dysregulation in adolescence. Worry dysregulation predicted elevated young adult anxiety in the second assessment during COVID-19, even after accounting for the first assessment.

Conclusion

This study identifies a developmental pathway from toddlerhood BI to young adults' elevated anxiety during the COVID-19 pandemic. Findings have implications for early identification of individuals at risk for dysregulated worry and the prevention of anxiety during stressful life events in young adulthood.Reprinted from J Am Acad Child Adolesc Psychiatry, 60, Zeytinoglu et al., A Developmental Pathway From Early Behavioral Inhibition to Young Adults' Anxiety During the COVID-19 Pandemic, pp. 1300-1308, copyright 2021, with permission from Elsevier.

Evaluating an internet-delivered fear conditioning and extinction protocol using response times and affective ratings

Pavlovian fear conditioning is widely used to study mechanisms of fear learning, but high-throughput studies are hampered by the labor-intensive nature of examining participants in the lab. To circumvent this bottle-neck, fear conditioning tasks have been developed for remote delivery. Previous studies have examined remotely delivered fear conditioning protocols using expectancy and affective ratings. Here we replicate and extend these findings using an internet-delivered version of the Screaming Lady paradigm, evaluating the effects on negative affective ratings and response time to an auditory probe during stimulus presentation. In a sample of 80 adults, we observed clear evidence of both fear acquisition and extinction using affective ratings. Response times were faster when probed early, but not later, during presentation of stimuli paired with an aversive scream. The response time findings are at odds with previous lab-based studies showing slower as opposed to faster responses to threat-predicting cues. The findings underscore the feasibility of employing remotely delivered fear conditioning paradigms with affective ratings as outcome. Findings further highlight the need for research examining optimal parameters for concurrent response time measures or alternate non-verbal indicators of conditioned responses in Pavlovian conditioning protocols.

Pathways from maternal shyness to adolescent social anxiety

BACKGROUND

Social anxiety is amongst the most prevalent adolescent mental health problems; however, it is often unrecognized due to its comorbidity with other anxiety problems such as generalized anxiety. Thus, understanding the unique developmental pathways to social anxiety is critical for improving its prevention. We examined the pathway from maternal shyness, when children were 4 years old, to adolescents' social anxiety at age 15 through social wariness at age 7. We hypothesized that childhood social wariness would mediate the association between maternal shyness and social anxiety in adolescence.

METHODS

Participants (N = 291; 54% female) were followed from early childhood to adolescence. Mothers reported on their own shyness when children were 4 years old. Social wariness toward unfamiliar peers was observed in the laboratory at ages 4 and 7. Adolescent social anxiety and generalized anxiety were assessed via self-report, parent-report, and clinical diagnoses at age 15.

RESULTS

Maternal shyness was positively associated with adolescent social anxiety but not generalized anxiety at age 15. Higher levels of maternal shyness at age 4 predicted greater social wariness at age 7, which in turn predicted greater social anxiety but not generalized anxiety at age 15. Social wariness at age 7 partially mediated the association between maternal shyness and adolescent social anxiety.

CONCLUSIONS

This study identifies a unique developmental pathway from maternal shyness to adolescent social anxiety. Findings suggest that childhood social wariness connects maternal shyness to adolescent social anxiety.

Reliability of task-evoked neural activation during face-emotion paradigms: Effects of scanner and psychological processes

Assessing and improving test–retest reliability is critical to efforts to address concerns about replicability of task‐based functional magnetic resonance imaging. The current study uses two statistical approaches to examine how scanner and task‐related factors influence reliability of neural response to face‐emotion viewing. Forty healthy adult participants completed two face‐emotion paradigms at up to three scanning sessions across two scanners of the same build over approximately 2 months. We examined reliability across the main task contrasts using Bayesian linear mixed‐effects models performed voxel‐wise across the brain. We also used a novel Bayesian hierarchical model across a predefined whole‐brain parcellation scheme and subcortical anatomical regions. Scanner differences accounted for minimal variance in temporal signal‐to‐noise ratio and task contrast maps. Regions activated during task at the group level showed higher reliability relative to regions not activated significantly at the group level. Greater reliability was found for contrasts involving conditions with clearly distinct visual stimuli and associated cognitive demands (e.g., face vs. nonface discrimination) compared to conditions with more similar demands (e.g., angry vs. happy face discrimination). Voxel‐wise reliability estimates tended to be higher than those based on predefined anatomical regions. This work informs attempts to improve reliability in the context of task activation patterns and specific task contrasts. Our study provides a new method to estimate reliability across a large number of regions of interest and can inform researchers' selection of task conditions and analytic contrasts.

A dynamic relation between whole-brain white matter microstructural integrity and anxiety symptoms in preadolescent females with pathological anxiety

Pathological anxiety typically emerges during preadolescence and has been linked to alterations in white matter (WM) pathways. Because myelination is critical for efficient neuronal communication, characterizing associations between WM microstructure and symptoms may provide insights into pathophysiological mechanisms associated with childhood pathological anxiety. This longitudinal study examined 182 girls enrolled between the ages of 9-11 that were treatment-naïve at study entry: healthy controls (n = 49), subthreshold-anxiety disorders (AD) (n = 82), or meeting DSM-5 criteria for generalized, social, and/or separation ADs (n = 51), as determined through structured clinical interview. Anxiety severity was assessed with the Clinical Global Impression Scale and Screen for Child Anxiety and Related Emotional Disorders (SCARED). Participants (n = 182) underwent clinical, behavioral, and diffusion tensor imaging (DTI) assessments at study entry, and those with pathological anxiety (subthreshold-AD and AD, n = 133) were followed longitudinally for up to 3 additional years. Cross-sectional ANCOVAs (182 scans) examining control, subthreshold-AD, and AD participants found no significant relations between anxiety and DTI measurements. However, in longitudinal analyses of girls with pathological anxiety (343 scans), linear mixed-effects models demonstrated that increases in anxiety symptoms (SCARED scores) were associated with reductions in whole-brain fractional anisotropy, independent of age (Std. β (95% CI) = -0.06 (-0.09 to -0.03), F(1, 46.24) = 11.90, P = 0.001). Using a longitudinal approach, this study identified a dynamic, within-participant relation between whole-brain WM microstructural integrity and anxiety in girls with pathological anxiety. Given the importance of WM microstructure in modulating neural communication, this finding suggests the possibility that WM development could be a viable target in the treatment of anxiety-related psychopathology.

Developmental Changes in the Association Between Cognitive Control and Anxiety

Anxiety has been associated with reliance on reactive (stimulus-driven/reflexive) control strategies in response to conflict. However, this conclusion rests primarily on indirect evidence. Few studies utilize tasks that dissociate the use of reactive ('just in time') vs. proactive (anticipatory/preparatory) cognitive control strategies in response to conflict, and none examine children diagnosed with anxiety. The current study utilizes the AX-CPT, which dissociates these two types of cognitive control, to examine cognitive control in youth (ages 8-18) with and without an anxiety diagnosis (n = 56). Results illustrate that planful behavior, consistent with using a proactive strategy, varies by both age and anxiety symptoms. Young children (ages 8-12 years) with high anxiety exhibit significantly less planful behavior than similarly-aged children with low anxiety. These findings highlight the importance of considering how maturation influences relations between anxiety and performance on cognitive-control tasks and have implications for understanding the pathophysiology of anxiety in children.

ENIGMA-anxiety working group: Rationale for and organization of large-scale neuroimaging studies of anxiety disorders

Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders.

Threat imminence reveals links among unfolding of anticipatory physiological response, cortical-subcortical intrinsic functional connectivity, and anxiety

Excessive expression of fear responses in anticipation of threat occurs in anxiety, but understanding of underlying pathophysiological mechanisms is limited. Animal research indicates that threat-anticipatory defensive responses are dynamically organized by threat imminence and rely on conserved circuitry. Insight from basic neuroscience research in animals on threat imminence could guide mechanistic research in humans mapping abnormal function in this circuitry to aberrant defensive responses in pathological anxiety. 50 pediatric anxiety patients and healthy-comparisons (33 females) completed an instructed threat-anticipation task whereby cues signaled delivery of painful (threat) or non-painful (safety) thermal stimulation. Temporal changes in skin-conductance indexed anxiety effects on anticipatory responding as function of threat imminence. Multivariate network analyses of resting-state functional connectivity data from a subsample were used to identify intrinsic-function correlates of anticipatory-response dynamics, within a specific, distributed network derived from translational research on defensive responding. By considering threat imminence, analyses revealed specific anxiety effects. Importantly, pathological anxiety was associated with excessive deployment of anticipatory physiological response as threat, but not safety, outcomes became more imminent. Magnitude of increase in threat-anticipatory physiological responses corresponded with magnitude of intrinsic connectivity within a cortical-subcortical circuit. Moreover, more severe anxiety was associated with stronger associations between anticipatory physiological responding and connectivity that ventromedial prefrontal cortex showed with hippocampus and basolateral amygdala, regions implicated in animal models of anxiety. These findings link basic and clinical research, highlighting variations in intrinsic function in conserved defensive circuitry as a potential pathophysiological mechanism in anxiety.

Mega-analysis methods in ENIGMA: The experience of the generalized anxiety disorder working group

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA-Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega-analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between-country transfer of subject-level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega-analyses.

Hyperbolic trade-off: The importance of balancing trial and subject sample sizes in neuroimaging

Here we investigate the crucial role of trials in task-based neuroimaging from the perspectives of statistical efficiency and condition-level generalizability. Big data initiatives have gained popularity for leveraging a large sample of subjects to study a wide range of effect magnitudes in the brain. On the other hand, most task-based FMRI designs feature a relatively small number of subjects, so that resulting parameter estimates may be associated with compromised precision. Nevertheless, little attention has been given to another important dimension of experimental design, which can equally boost a study's statistical efficiency: the trial sample size. The common practice of condition-level modeling implicitly assumes no cross-trial variability. Here, we systematically explore the different factors that impact effect uncertainty, drawing on evidence from hierarchical modeling, simulations and an FMRI dataset of 42 subjects who completed a large number of trials of cognitive control task. We find that, due to an approximately symmetic hyperbola-relationship between trial and subject sample sizes in the presence of relatively large cross-trial variability, 1) trial sample size has nearly the same impact as subject sample size on statistical efficiency; 2) increasing both the number of trials and subjects improves statistical efficiency more effectively than focusing on subjects alone; 3) trial sample size can be leveraged alongside subject sample size to improve the cost-effectiveness of an experimental design; 4) for small trial sample sizes, trial-level modeling, rather than condition-level modeling through summary statistics, may be necessary to accurately assess the standard error of an effect estimate. We close by making practical suggestions for improving experimental designs across neuroimaging and behavioral studies.

Phasic Versus Tonic Irritability: Differential Associations With Attention-Deficit/Hyperactivity Disorder Symptoms

OBJECTIVE

Irritability is a multifaceted construct in pediatric psychopathology. It has been conceptualized as having a phasic dimension and a tonic dimension. Disruptive mood dysregulation disorder is defined by the presence of both dimensions. Severe irritability, or disruptive mood dysregulation disorder, is highly comorbid with attention-deficit/hyperactivity disorder (ADHD). However, it is unknown whether the presence of ADHD modulates the expression of phasic and tonic irritability.

METHOD

A data-driven, latent variable approach was used to examine irritability and ADHD symptoms in a transdiagnostic pediatric sample (N = 489) with primary disruptive mood dysregulation disorder, ADHD, subclinical irritability symptoms, or no diagnosis. Using latent profile analyses, we identified 4 classes: high levels of both irritability and ADHD symptoms, high levels of irritability and moderate levels of ADHD symptoms, moderate levels of irritability and high levels of ADHD symptoms, and low levels of both irritability and ADHD symptoms. Confirmatory factor analysis operationalized phasic irritability and tonic irritability.

RESULTS

As expected, the 2 latent classes characterized by high overall irritability exhibited the highest levels of both phasic and tonic irritability. However, between these 2 high irritability classes, highly comorbid ADHD symptoms were associated with significantly greater phasic irritability than were moderately comorbid ADHD symptoms. In contrast, the 2 high irritability groups did not differ on levels of tonic irritability.

CONCLUSION

These findings suggest that phasic, but not tonic, irritability has a significant association with ADHD symptoms and that phasic and tonic might be distinct, though highly related, irritability dimensions. Future research should investigate potential mechanisms underlying this differential association.

Location-dependent threat and associated neural abnormalities in clinical anxiety

Anxiety disorders are characterized by maladaptive defensive responses to distal or uncertain threats. Elucidating neural mechanisms of anxiety is essential to understand the development and maintenance of anxiety disorders. In fMRI, patients with pathological anxiety (ANX, n = 23) and healthy controls (HC, n = 28) completed a contextual threat learning paradigm in which they picked flowers in a virtual environment comprising a danger zone in which flowers were paired with shock and a safe zone (no shock). ANX compared with HC showed 1) decreased ventromedial prefrontal cortex and anterior hippocampus activation during the task, particularly in the safe zone, 2) increased insula and dorsomedial prefrontal cortex activation during the task, particularly in the danger zone, and 3) increased amygdala and midbrain/periaqueductal gray activation in the danger zone prior to potential shock delivery. Findings suggest that ANX engage brain areas differently to modulate context-appropriate emotional responses when learning to discriminate cues within an environment.

Suarez-Jimenez and colleagues use a shock and safe zone experiment with fMRI imaging to examine how pathological anxiety disorders are manifested in the brain. Their findings suggest that safe and dangerous zones within the experiment alter activation in different brain regions.