Extinction learning in childhood anxiety disorders, obsessive compulsive disorder and post-traumatic stress disorder: implications for treatment

The impact of the left inferior frontal gyrus on fear extinction: A transcranial direct current stimulation study

INTRODUCTION

Fear extinction is a fundamental component of exposure-based therapies for anxiety-related disorders. The renewal of fear in a different context after extinction highlights the importance of contextual factors. In this study, we aimed to investigate the causal role of the left inferior frontal gyrus (LiFG) in the context-dependency of fear extinction learning via administration of transcranial direct current stimulation (tDCS) over this area.

METHODS

180 healthy subjects were assigned to 9 groups: 3 tDCS conditions (anodal, cathodal, and sham) × 3 context combinations (AAA, ABA, and ABB). The fear conditioning/extinction task was conducted over three consecutive days: acquisition, extinction learning, and extinction recall. tDCS (2 mA, 10min) was administered during the extinction learning phase over the LiFG via a 4-electrode montage. Skin conductance response (SCR) data and self-report assessments were collected.

RESULTS

During the extinction learning phase, groups with excitability-enhancing anodal tDCS showed a significantly higher fear response to the threat cues compared to cathodal and sham stimulation conditions, irrespective of contextual factors. This effect was stable until the extinction recall phase. Additionally, excitability-reducing cathodal tDCS caused a significant decrease of the response difference between the threat and safety cues during the extinction recall phase. The self-report assessments showed no significant differences between the conditions throughout the experiment.

CONCLUSION

Independent of the context, excitability enhancement of the LiFG did impair fear extinction, and led to preservation of fear memory. In contrast, excitability reduction of this area enhanced fear extinction retention. These findings imply that the LiFG plays a role in the fear extinction network, which seems to be however context-independent.

Cognitive Behavioral Therapy for Anxiety and Depression in Children and Adolescents

Anxiety and depression are prevalent and impairing psychiatric problems for children and adolescents. In this review, the authors summarize information about their prevalence and impact, the most common assessment methods, the main components of cognitive behavioral therapy (CBT), and research on the effectiveness of CBT for these disorders. Future directions, including improving access to CBT through technology-based approaches and increasing personalization of treatment, are discussed.

Targeting intolerance of uncertainty in treatment: A meta-analysis of therapeutic effects, treatment moderators, and underlying mechanisms

OBJECTIVE

Anxiety-related disorders are among the most prevalent psychiatric conditions and cause significant impairment. Intolerance of uncertainty (IU) contributes to the emergence, maintenance, and symptom severity of anxiety-related disorders, yet information regarding treatment-related changes in IU is limited. This systematic review and meta-analysis examined the efficacy of evidence-based treatments for anxiety-related disorders on IU, explored factors moderating treatment effects of IU, and examined whether therapeutic improvement in IU corresponded with improvements in anxiety symptom severity.

METHODS

PubMED and PsycINFO were searched for randomized controlled trials (RCTs) using the terms "intolerance of uncertainty" AND "treatment" OR "therapy." Data for pre and post-treatment measures and patient, intervention, and trial-level characteristics were extracted from 28 RCTs. Separate random effects models examined the treatment efficacy of interventions on IU and symptom severity. Moderators of therapeutic effects were analyzed via method-of-moments meta-regression or an analog to the analysis of variance.

RESULTS

Across RCTs, interventions exhibited a large therapeutic effect on IU compared to control conditions (g = 0.89). Treatment effects on IU positively corresponded with improved symptom severity and accounted for 36 % of the variance. Interestingly, comorbid depression and certain treatment approaches were associated with larger improvements in IU.

CONCLUSION

Evidence-based treatments are effective in improving IU, highlighting the importance of IU in the treatment of anxiety-related disorders. Moderator analyses identified patient and intervention-level factors to inform approaches to improve therapeutic effects on IU. Future research is needed to optimize interventions targeting IU and evaluate long-term efficacy of interventions on IU for anxiety-related disorders.

The relationship of posttraumatic stress disorder and developmental trauma disorder with childhood psychopathology: A network analysis

OBJECTIVE

Potentially traumatic experiences are a major risk factor for mental disorders in children and adolescents. Posttraumatic psychopathology includes trauma-specific disorders such as posttraumatic stress disorder (PTSD) as well as other psychiatric disorders. Developmental Trauma Disorder (DTD) has been proposed as a developmentally sensitive diagnosis. We aimed to further illuminate the co-occurrence of psychiatric conditions with DTD and PTSD.

METHOD

In a convenience sample of families of 507 children and adolescents (mean age = 12.11 years old, SD = 2.92; 48.5% female), we assessed DTD, PTSD, and screened for psychiatric disorders. We estimated network models including DTD, PTSD and ten psychiatric conditions.

RESULTS

We found that DTD and PTSD share both common and differential comorbidity features on disorder-, domain-, and symptom-level. The differential comorbidity patterns of the DTD and PTSD domains placed DTD close to both externalizing and internalizing psychopathology while PTSD was primarily linked to internalizing conditions.

CONCLUSIONS

Our study provides evidence for the complex clinical presentation of posttraumatic psychopathology over and above PTSD in children. DTD and PTSD provide useful and distinct diagnostic categories for children who are also experiencing internalizing conditions, and DTD may be especially relevant for children who are experiencing externalizing psychopathology.

On making (and turning adaptive to) maladaptive aversive memories in laboratory rodents

Fear conditioning and avoidance tasks usually elicit adaptive aversive memories. Traumatic memories are more intense, generalized, inflexible, and resistant to attenuation via extinction- and reconsolidation-based strategies. Inducing and assessing these dysfunctional, maladaptive features in the laboratory are crucial to interrogating posttraumatic stress disorder's neurobiology and exploring innovative treatments. Here we analyze over 350 studies addressing this question in adult rats and mice. There is a growing interest in modeling several qualitative and quantitative memory changes by exposing already stressed animals to freezing- and avoidance-related tests or using a relatively high aversive training magnitude. Other options combine aversive/fearful tasks with post-acquisition or post-retrieval administration of one or more drugs provoking neurochemical or epigenetic alterations reported in the trauma aftermath. It is potentially instructive to integrate these procedures and incorporate the measurement of autonomic and endocrine parameters. Factors to consider when defining the organismic and procedural variables, partially neglected aspects (sex-dependent differences and recent vs. remote data comparison) and suggestions for future research (identifying reliable individual risk and treatment-response predictors) are discussed.

Fear-potentiated startle reveals diminished threat extinction in pathological anxiety

BACKGROUND

Major theories propose that perturbed threat learning is central to pathological anxiety, but empirical support is inconsistent. Failures to detect associations with anxiety may reflect limitations in quantifying conditioned responses to anticipated threat, and hinder translation of theory into empirical work. In prior work, we could not detect threat-specific anxiety effects on states of conditioned threat using psychophysiology in a large sample of patients and healthy comparisons. Here, we examine the utility of an alternative fear potentiated startle (FPS) scoring in revealing associations between anxiety and threat conditioning and extinction in this dataset. Secondary analyses further explored associations among conditioned threat responses, subcortical morphometry, and treatment outcomes.

METHODS

Youths and adults with anxiety disorders and healthy comparisons (n = 306; 178 female participants; 8-50 years) previously completed a well-validated differential threat learning paradigm. FPS and skin conductance response (SCR) quantified psychophysiological responses during threat conditioning and extinction. In this report, we examined normalizing raw FPS scores to intertrial intervals (ITI) to address challenges in more common approaches to FPS scoring which could mask group effects. Secondary analyses examined associations between FPS and subcortical morphometry and with response to exposure-based cognitive behavioral therapy in a subsample of patients.

RESULTS

Patients and comparisons showed comparable differential threat conditioning using FPS and SCR. While SCR suggested comparable extinction between groups, FPS revealed stronger retention of threat contingency during extinction in individuals with anxiety disorders. Extinction indexed with FPS was not associated with age, morphometry, or anxiety treatment outcome.

CONCLUSION

ITI-normalized FPS may have utility in detecting difficulties in extinguishing conditioned threat responses in anxiety. These findings provide support for extinction theories of anxiety and encourage continued research on aberrant extinction in pathological anxiety.

Common and separable behavioral and neural mechanisms underlie the generalization of fear and disgust

Generalization represents the transfer of a conditioned responses to stimuli that resemble the conditioned stimulus (CS). Previous studies on generalization of defensive avoidance responses have primarily focused on fear and have neglected disgust generalization, which represents a key pathological mechanism in some anxiety disorders. In the present study we examined common and distinct mechanisms of fear and disgust generalization by means of a fear or disgust multi-CS conditioning and generalization paradigm with concomitant event-related potential (ERPs) acquisition in n = 62 subjects. We demonstrate that compared to fear, disgust-relevant generalized stimuli (GS) elicited larger expectancy ratings and longer reaction times (RTs) reflecting stronger ratings of 'risk'. On the electrophysiological level, increased P2 amplitudes were found in response to conditioned CS+ versus CS- across both domains, possibly reflecting higher motivational and attentional salience of aversive conditioned stimuli per se. Contingent negative variation (CNV) amplitude was significantly larger for disgust-CS+ than disgust-CS-, reflecting a stronger preparation of the disgust US. Additionally, we found that the contingent negative variation (CNV) fear generalization gradient, and CNV amplitude were increased with similarity to CS+. In contrast the CNV to disgust-GS did not differ and did not reflect disgust generalization. Together this may indicate that the CNV represents a highly fear-specific index for generalization learning. This study provides the first neurobiological evidence for common and distinct generalization learning in fear versus disgust suggesting that dysregulations in separable defensive avoidance mechanisms may underly different anxiety disorder subtypes.

Interpretation Bias and Anticipated Distress in the Face of Ambiguity: Predictors of Change in Cognitive Behavioral Therapy for Youth Anxiety

This study examined associations among children's anxiety, interpretation bias, and anticipated distress before and after cognitive behavioral therapy (CBT) and investigated baseline levels of interpretation bias and anticipated distress as well as changes in these cognitive biases following treatment as predictors of treatment outcome. Clinically anxious youth (N = 39) were treated with brief CBT augmented with a smartphone app. Children completed measures assessing their anxiety, interpretation bias, and anticipated distress at baseline, post-treatment, and 2-month follow-up. Children's anxiety, interpretation bias, and anticipated distress significantly decreased following treatment. Anticipated distress was associated with higher anxiety at all time points; however, interpretation bias was not significantly associated with anxiety before or after treatment. Reductions in anticipated distress following treatment predicted concurrent and prospective reductions in anxiety. Reduced anticipated distress following treatment may contribute to enhanced treatment outcomes and may be more strongly related to the maintenance of youth anxiety than interpretation bias.

Toward an empirically based Developmental Trauma Disorder diagnosis and semi-structured interview for children: The DTD field trial replication

OBJECTIVE

Developmental trauma disorder (DTD) is a childhood psychiatric syndrome designed to include sequelae of trauma exposure not fully captured by PTSD. This study aimed to determine whether the assessment of DTD with an independent sample of children in mental health treatment will replicate results from an initial validation study.

METHODS

The DTD semi-structured interview (DTD-SI) was administered to a convenience sample in six sites in the United States (N = 271 children in mental health care, 8-18 years old, 47% female, 41% Black or Latinx) with measures of trauma history, DSM-IV PTSD, probable DSM-IV psychiatric diagnoses, emotion regulation/dysregulation, internalizing/externalizing problems, and quality of life. Confirmatory factor (CFA) and item response theory (IRT) analyses tested DTD's structure and DTD-SI's information value. Bivariate and multivariate analyses tested DTD's criterion and convergent validity.

RESULTS

A three-factor solution (i.e., emotion/somatic, attentional/behavioral, and self/relational dysregulation) best fit the data (CFI = 0.91; TLI = 0.89; BIC = 357.17; RMSEA = 0.06; SRMR = 0.05). DTD-SI items were informative across race/ethnicity, gender, and age with three exceptions. Emotion dysregulation was the most informative item at low levels of DTD severity. Non-suicidal self-injury was rare but discriminative in identifying children with high levels of DTD severity. Results supported the criterion and convergent validity of the DTD construct.

CONCLUSION

This replication provides empirical support for DTD as a construct and potential psychiatric syndrome, and the DTD-SI's validity as a clinical research tool.

A cholinergic medial septum input to medial habenula mediates generalization formation and extinction of visual aversion

Generalization of visual aversion is a critical function of the brain that supports survival, but the underlying neurobiological mechanisms are unclear. We establish a rapid generalization procedure for inducing visual aversion by dynamic stripe images. By using fiber photometry, apoptosis, chemogenetic and optogenetic techniques, and behavioral tests, we find that decreased cholinergic neurons' activity in the medial septum (MS) leads to generalization loss of visual aversion. Strikingly, we identify a projection from MS cholinergic neurons to the medial habenula (MHb) and find that inhibition of the MS→MHb cholinergic circuit disrupts aversion-generalization formation while its continuous activation disrupts subsequent extinction. Further studies show that MS→MHb cholinergic projections modulate the generalization of visual aversion possibly via M1 muscarinic acetylcholine receptors (mAChRs) of downstream neurons coreleasing glutamate and acetylcholine. These findings reveal that the MS→MHb cholinergic circuit is a critical node in aversion-generalization formation and extinction and potentially provides insight into the pathogenesis of affective disorders.

High vagal tone and rapid extinction learning as potential transdiagnostic protective factors following childhood violence exposure

Childhood exposure to violence is strongly associated with psychopathology. High resting respiratory sinus arrhythmia (RSA) is associated with lower levels of psychopathology in children exposed to violence. High RSA may help to protect against psychopathology by facilitating fear extinction learning, allowing more flexible autonomic responses to learned threat and safety cues. In this study, 165 youth (79 female, aged 9-17; 86 exposed to violence) completed assessments of violence exposure, RSA, and psychopathology, and a fear extinction learning task; 134 participants returned and completed psychopathology assessments 2 years later. Resting RSA moderated the longitudinal association of violence exposure with post-traumatic stress disorder (PTSD) symptoms and externalizing psychopathology, such that the association was weaker among youths with higher RSA. Higher skin conductance responses (SCR) during extinction learning to the threat cue (CS+) was associated with higher internalizing symptoms at follow-up and greater SCR to the safety cue (CS-) was associated with higher PTSD, internalizing, and externalizing symptoms, as well as the p-factor, controlling for baseline symptoms. Findings suggest that higher RSA may protect against emergence of psychopathology among children exposed to violence. Moreover, difficulty extinguishing learned threat responses and elevated autonomic responses to safety cues may be associated with risk for future psychopathology.

Safety learning during development: Implications for development of psychopathology

Fear and safety learning are necessary adaptive behaviors that develop over the course of maturation. While there is a large body of literature regarding the neurobiology of fear and safety learning in adults, less is known regarding safety learning during development. Given developmental changes in the brain, there are corresponding changes in safety learning that are quantifiable; these may serve to predict risk and point to treatment targets for fear and anxiety-related disorders in children and adolescents. For healthy, typically developing youth, the main developmental variation observed is reduced discrimination between threat and safety cues in children compared to adolescents and adults, while lower expression of extinction learning is exhibited in adolescents compared to adults. Such distinctions may be related to faster maturation of the amygdala relative to the prefrontal cortex, as well as incompletely developed functional circuits between the two. Fear and anxiety-related disorders, childhood maltreatment, and behavioral problems are all associated with alterations in safety learning for youth, and this dysfunction may proceed into adulthood with corresponding abnormalities in brain structure and function-including amygdala hypertrophy and hyperreactivity. As impaired inhibition of fear to safety may reflect abnormalities in the developing brain and subsequent psychopathology, impaired safety learning may be considered as both a predictor of risk and a treatment target. Longitudinal neuroimaging studies over the course of development, and studies that query change with interventions are needed in order to improve outcomes for individuals and reduce long-term impact of developmental psychopathology.

Optimising Exposure for Children and Adolescents with Anxiety, OCD and PTSD: A Systematic Review

Cognitive behavioural therapy is an effective treatment for anxiety disorders in children and young people; however, many do not benefit. Behavioural exposure appears to be the critical ingredient in the treatment of anxiety disorders. Research with adults has identified innovative strategies to optimise exposure-based treatments, yet it is not clear how to optimise the effects of exposure for children and young people. This review was a preliminary exploration of the association between potential optimisation strategies and treatment procedures and outcomes for the treatment of child anxiety symptoms/disorders. We searched Psych-Info and Medline databases using a systematic search strategy and identified 29 articles. We found preliminary evidence that some specific strategies may enhance the effects of exposure, such as dropping safety behaviours, parents and therapists discouraging avoidance, and the use of homework. However, not one significant finding was replicated by another study for the same timepoint using the same methodology. To a large degree, this lack of replication reflects a limited number of studies combined with a lack of consistency across studies around conceptualisations, methodological approaches, and outcome measures making it difficult to make meaningful comparisons between studies and draw firm conclusions. Examination is needed of a wide range of theoretically-driven potential optimisation strategies using methodologically robust, preclinical studies with children and young people. Furthermore, the methods used in future research must enable comparisons across studies and explore developmental differences in the effects of particular optimisation strategies.

Real-world efficacy of deep TMS for obsessive-compulsive disorder: Post-marketing data collected from twenty-two clinical sites

BACKGROUND

Deep transcranial magnetic stimulation (dTMS) with the H7-coil was FDA cleared for obsessive-compulsive disorder (OCD) in August 2018 based on multicenter sham-controlled studies. Here we look at the efficacy of dTMS for OCD in real world practices.

METHODS

All dTMS clinics were asked to supply their data on treatment details and outcome measures. The primary outcome measure was response, defined by at least a 30% reduction in the Yale Brown Obsessive Compulsive Scale (YBOCS) score from baseline to endpoint. Secondary outcome measures included first response, defined as the first time the YBOCS score has met response criteria, and at least one-month sustained response. Analyses included response rate at the endpoint (after 29 dTMS sessions), number of sessions and days required to reach first response and sustained response.

RESULTS

Twenty-two clinical sites with H7-coils provided data on details of treatment and outcome (YBOCS) measures from a total of 219 patients. One-hundred-sixty-seven patients who had at least one post-baseline YBOCS measure were included in the main analyses. Overall first and sustained response rates were 72.6% and 52.4%, respectively. The response rate was 57.9% in patients who had YBOCS scores after 29 dTMS sessions. First response was achieved in average after 18.5 sessions (SD = 9.4) or 31.6 days (SD = 25.2). Onset of sustained one-month response was achieved in average after 20 sessions (SD = 9.8) or 32.1 days (SD = 20.5). Average YBOCS scores demonstrated continuous reduction with increasing numbers of dTMS sessions.

CONCLUSIONS

In real-world clinical practice, the majority of OCD patients benefitted from dTMS, and the onset of improvement usually occurs within 20 sessions. Extending the treatment course beyond 29 sessions results in continued reduction of OCD symptoms, raising the prospect of value for extended treatment protocols in non-responders.

Knowledge and competency standards for specialized cognitive behavior therapy for pediatric obsessive-compulsive disorder

Although exposure-based cognitive behavior therapy (CBT) and pharmacotherapy have demonstrated efficacy for obsessive-compulsive disorder (OCD), the lack of clinicians effectively trained in these treatments significantly limit effective intervention options for affected youth. This is very unfortunate since child onset is reported by 50% of adults with OCD. To ameliorate this serious global issue the 14 nation International Obsessive-Compulsive Disorders Accreditation Task Force (ATF) of The Canadian Institute for Obsessive Compulsive Disorders (CIOCD) has developed knowledge and competency standards recommended for specialized treatments for OCD through the lifespan. Currently available guidelines are considered by experts to be essential but insufficient because there are not enough clinicians with requisite knowledge and competencies to effectively treat OCD. This manuscript presents knowledge and competency standards recommended for specialized cognitive behavior therapy (CBT) for pediatric OCD, derived from comprehensive literature review and expert synthesis. In addition to standards covering the elements of individual CBT-based assessment and treatment, family and school interventions are addressed given the critical role these domains play in the psychosocial development of youths. The ATF standards presented in these phase two papers will be foundational to the upcoming development of certification (individuals) and accreditation (sites) for specialized treatments in OCD through the lifespan.

Specialty knowledge and competency standards for pharmacotherapy for pediatric obsessive-compulsive disorder

Evidence based treatments for pediatric Obsessive-Compulsive Disorder (OCD) are delivered with varying levels of expertise. This paper is part of the phase two series by the International OCD Accreditation Task Force (ATF) to advance a standardized high level of care globally. This paper presents specific knowledge and competencies recommended for specialized practice for pediatric psychopharmacologists working with OCD, developed by an international group of clinicians with extensive expertise in assessment and treatment of OCD. Tabulated knowledge and competency standards are operationalized as clinician abilities with specification of evidence for each standard. The distinction between current practice guidelines and ATF standards is discussed. Drug treatment has a solid evidence base. However, it should not be applied isolated, but informed by broad competence in general child and adolescent psychiatry and pediatrics. Other treatment relevant areas such as specialty CBT, family functioning, developmental issues, and neurobiology require consideration. Drug treatment includes several phases with varying degrees of evidence: Starting up medication, titration to maximum tolerated dose, maintenance, termination, and relapse prevention. In complex cases, pharmacotherapy with weak evidence may be needed to target symptoms and/or co-morbidity. The ATF knowledge and competency standards presented will be reviewed and updated commensurate with research.

Neural correlates of cognitive behavioral therapy response in youth with negative valence disorders: A systematic review of the literature

BACKGROUND

Cognitive-behavioral therapy (CBT) is the gold-standard psychotherapeutic treatment for pediatric negative valence disorders. However, some youths do not respond optimally to treatment, which may be due to variations in neural functioning.

METHODS

We systematically reviewed functional magnetic resonance imaging studies in youths with negative valence disorders to identify pre- and post-treatment neural correlates of CBT response.

RESULTS

A total of 21 studies were identified, of overall weak to moderate quality. The most consistent findings across negative valence disorders consisted of associations of treatment response with pre- and post-treatment task-based activation and/or functional connectivity within and between the prefrontal cortex, the medial temporal lobe, and other limbic regions. Associations of CBT response with baseline and/or post-treatment activity in the striatum, precentral and postcentral gyri, medial and posterior cingulate cortices, and parietal cortex, connectivity within and between the default-mode, cognitive control, salience, and frontoparietal networks, and metrics of large-scale brain network organization, were also reported, although less consistently.

LIMITATIONS

The poor quality and limited number of studies and the important heterogeneity of study designs and results considerably limit the conclusions that can be drawn from this literature.

CONCLUSIONS

Despite these limitations, these findings provide preliminary evidence suggesting youths presenting certain patterns of brain function may respond better to CBT, whereas others may benefit from alternative or augmented forms of treatment.

Harmonizing the Neurobiology and Treatment of Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a common, chronic, and oftentimes disabling disorder. The only established first-line treatments for OCD are exposure and response prevention, and serotonin reuptake inhibitor medications (SRIs). However, a subset of patients fails to respond to either modality, and few experience complete remission. Beyond SRI monotherapy, antipsychotic augmentation is the only medication approach for OCD with substantial empirical support. Our incomplete understanding of the neurobiology of OCD has hampered efforts to develop new treatments or enhance extant interventions. This review focuses on several promising areas of research that may help elucidate the pathophysiology of OCD and advance treatment. Multiple studies support a significant genetic contribution to OCD, but pinpointing the specific genetic determinants requires additional investigation. The preferential efficacy of SRIs in OCD has neither led to discovery of serotonergic abnormalities in OCD nor to development of new serotonergic medications for OCD. Several lines of preclinical and clinical evidence suggest dysfunction of the glutamatergic system in OCD, prompting testing of several promising glutamate modulating agents. Functional imaging studies in OCD show consistent evidence for increased activity in brain regions that form a cortico-striato-thalamo-cortical (CSTC) loop. Neuromodulation treatments with either noninvasive devices (e.g., transcranial magnetic stimulation) or invasive procedures (e.g., deep brain stimulation) provide further support for the CSTC model of OCD. A common substrate for various interventions (whether drug, behavioral, or device) may be modulation (at different nodes or connections) of the CSTC circuit that mediates the symptoms of OCD.

Psychiatric comorbidity of developmental trauma disorder and posttraumatic Stress disorder: findings from the DTD field trial replication (DTDFT-R)

Background: Developmental Trauma Disorder (DTD) has extensive comorbidity with internalizing and externalizing disorders distinct from posttraumatic stress disorder (PTSD). Objective: To replicate findings of DTD comorbidity and to determine whether this comorbidity is distinct from, and extends beyond, comorbidities of PTSD. Method: DTD was assessed by structured interview, and probable DSM-IV psychiatric disorders were identified with KSADS-PL screening modules, in a multi-site sample of 271 children (ages 8-18 years old; 47% female) in outpatient or residential mental health treatment for multiple (M = 3.5 [SD = 2.4]) psychiatric diagnoses other than PTSD or DTD. Results: DTD (N = 74, 27%) and PTSD (N = 107, 39%) were highly comorbid and shared several DSM-IV internalizing and externalizing disorder comorbidities. Children with DTD with or without PTSD had more comorbid diagnoses (M = 5.7 and 5.2 [SD = 2.4 and 1.7], respectively) than children with PTSD but not DTD (M = 3.8[SD = 2.1]) or neither PTSD nor DTD (M = 2.1[SD = 1.9]), F[3,267] = 55.49, p < .001. Further, on a multivariate basis controlling for demographics and including all potential comorbid disorders, DTD was associated with separation anxiety disorder, depression, and oppositional defiant disorder after controlling for PTSD, while PTSD was associated only with separation anxiety disorder after controlling for DTD. Both DTD and PTSD were associated with suicidality. Conclusions: DTD is associated with psychiatric comorbidity beyond that of PTSD, and DTD warrants assessment for treatment planning with children in intensive psychiatric services.

Conceptualizing eating disorder psychopathology using an anxiety disorders framework: Evidence and implications for exposure-based clinical research

Eating disorders (EDs) and anxiety disorders (ADs) evidence shared risk and significant comorbidity. Recent advances in understanding of anxiety-based disorders may have direct application to research and treatment efforts for EDs. The current review presents an up-to-date, behavioral conceptualization of the overlap between anxiety-based disorders and EDs. We identify ways in which anxiety presents in EDs, consider differences between EDs and ADs relevant to treatment adaptions, discuss how exposure-based strategies may be adapted for use in ED treatment, and outline directions for future mechanistic, translational, and clinical ED research from this perspective. Important research directions include: simultaneous examination of the extent to which EDs are characterized by aberrant avoidance-, reward-, and/or habit-based neurobiological and behavioral processes; improvement in understanding of how nutritional status interacts with neurobiological characteristics of EDs; incorporation of a growing knowledge of biobehavioral signatures in ED treatment planning; development of more comprehensive exposure-based treatment approaches for EDs; testing whether certain exposure interventions for AD are appropriate for EDs; and improvement in clinician self-efficacy and ability to use exposure therapy for EDs.

Alterations in fear extinction neural circuitry and fear-related behavior linked to trauma exposure in children

Exposure to childhood trauma is extremely common (>60 %) and is a leading risk factor for fear-based disorders, including anxiety and posttraumatic stress disorder. These disorders are characterized by deficits in fear extinction and dysfunction in underlying neural circuitry. Given the strong and pervasive link between childhood trauma and the development of psychopathology, fear extinction may be a key mechanism. The present study tests the impact of childhood trauma exposure on fear extinction and underlying neural circuitry. Children (N = 44, 45 % trauma-exposed; 6-11 yrs) completed a novel two-day virtual reality fear extinction experiment. On day one, participants underwent fear conditioning and extinction. Twenty-four hours later, participants completed a test of extinction recall during fMRI. Conditioned fear was measured throughout the experiment using skin conductance and fear-related behavior, and activation in fear-related brain regions was estimated during recall. There were no group differences in conditioned fear during fear conditioning or extinction learning. During extinction recall, however, trauma-exposed children kept more distance from both the previously extinguished and the safety cue, suggesting poor differentiation between threat and safety cues. Trauma-exposed youth also failed to approach the previously extinguished cue over the course of extinction recall. The effects on fear-related behavior during extinction recall were accompanied by higher activation to the previously extinguished cue in fear-relevant brain regions, including the dorsal anterior cingulate cortex and anterior insula, in trauma-exposed relative to control children. Alterations in fear-related brain regions and fear-related behavior may be a core mechanism through which childhood trauma confers heightened vulnerability to psychopathology.

Adolescent Vulnerability to Heightened Emotional Reactivity and Anxiety After Brief Exposure to an Obesogenic Diet

BACKGROUND

Emerging evidence demonstrates that diet-induced obesity disrupts corticolimbic circuits underlying emotional regulation. Studies directed at understanding how obesity alters brain and behavior are easily confounded by a myriad of complications related to obesity. This study investigated the early neurobiological stress response triggered by an obesogenic diet. Furthermore, this study directly determined the combined impact of a short-term obesogenic diet and adolescence on critical behavioral and molecular substrates implicated in emotion regulation and stress.

METHODS

Adolescent (postnatal day 31) or adult (postnatal day 81) Lewis rats were fed for 1 week with an experimental Western-like high-saturated fat diet (WD, 41% kcal from fat) or a matched control diet (CD, 13% kcal from fat). We used the acoustic fear-potentiated startle (FPS) paradigm to determine the effects of the WD on cued fear conditioning and fear extinction. We used c-Fos mapping to determine the functional influence of the diet and stress on corticolimbic circuits.

RESULTS

We report that 1-week WD consumption was sufficient to induce fear extinction deficits in adolescent rats, but not in adult rats. We identify fear-induced alterations in corticolimbic neuronal activation and demonstrate increased prefrontal cortex CRHR1 messenger RNA (mRNA) levels in the rats that consumed the WD.

CONCLUSION

Our findings demonstrate that short-term consumption of an obesogenic diet during adolescence heightens behavioral and molecular vulnerabilities associated with risk for anxiety and stress-related disorders. Given that fear extinction promotes resilience and that fear extinction principles are the foundation of psychological treatments for posttraumatic stress disorder (PTSD), understanding how obesogenic environments interact with the adolescent period to affect the acquisition and expression of fear extinction memories is of tremendous clinical relevance.

Activation of mineralocorticoid receptors facilitate the acquisition of fear memory extinction and impair the generalization of fear memory in diabetic animals

RATIONALE

Studies point out a higher prevalence of posttraumatic stress disorder (PTSD) in individuals with diabetes mellitus. It is known that glucocorticoid (GR) and mineralocorticoid (MR) receptors are implicated in fear memory processes and PTSD. However, there is no preclinical studies addressing the involvement of these receptors on abnormal fear memories related to diabetic condition.

OBJECTIVES

By inducing a contextual conditioned fear memory, we generate a suitable condition to investigate the extinction and the generalization of the fear memory in streptozotocin-induced diabetic (DBT) rats alongside the expression of the cytosolic and nuclear GR and MR in the hippocampus (HIP) and prefrontal cortex (PFC). Moreover, we investigated the involvement of the MR or GR on the acquisition of fear memory extinction and on the generalization of this fear memory. When appropriate, anxiety-related behavior was evaluated.

METHODS

Male Wistar rats received one injection of steptozotocin (i.p.) to induce diabetes. After 4 weeks, the animals (DBTs and non-DBTs) were subjected to a conditioned contextual fear protocol.

RESULTS

The expression of MR and GR in the HIP and PFC was similar among all the groups. The single injection of MR agonist was able to facilitate the acquisition of the impaired fear memory extinction in DBTs animals together with the impairment of its generalization. However, the GR antagonism impaired only the generalization of this fear memory which was blocked by the previous injection of the MR antagonist. All treatments were able to exert anxiolytic-like effects.

CONCLUSIONS

The results indicate that MR activation in DBT animals disrupts the overconsolidation of aversive memory, without discarding the involvement of emotional behavior in these processes.

A Method to Provoke Obsessive Compulsive Symptoms for Basic Research and Clinical Interventions

The efficacy of deep repetitive transcranial magnetic stimulation (dTMS) for obsessive compulsive disorder (OCD) was recently confirmed in a Food and Drug Administration-regulated, multicenter, sham-controlled study. In this study, patients who failed pharmacotherapy underwent individually tailored provocations just prior to each stimulation session, in the attempt to activate the relevant circuitry and making it labile to change. The procedure that was developed reliably evoked moderate intensity symptoms, making it effective on the one hand and mild enough to allow the patient to continue with the dTMS session on the other. This methodology article describes in a detailed step wise fashion how to evaluate the patient's specific symptoms and design the individualized provocations. Additionally, the article explains how to instruct relevant personnel to administer the provocations, gauge their efficacy, and overcome possible obstacles. This method, apart from its ongoing role in the clinical treatment of OCD by dTMS, may be used for provocation of symptoms in basic studies [e.g., imaging with Electroencephalogram (EEG) or Functional magnetic resonance imaging fMRI] as well as other treatments.

Fear conditioning and extinction in anxious youth, offspring at-risk for anxiety and healthy comparisons: An fMRI study

Dysfunctions in fronto-amygdala circuitry have been linked to anxiety. Questions remain regarding the impact of familial-risk and ongoing anxiety on such circuitry function, especially in youth. Using fMRI fear conditioning and extinction paradigms, we examined these relationships in 10-17 year-olds: 22 youth with an anxiety disorder, 22 healthy youth born to parents with past or current anxiety disorders (at risk), and 32 healthy comparisons. Skin conductance responses and subjective fear ratings were also assessed. During conditioning, healthy comparisons showed differential activation (CS + >CS-) in regions of the fronto-amygdala circuitry. In comparison, the at-risk group showed greater activation to the safety cue (CS - >CS+) in the amygdala and dorsolateral prefrontal cortex. Failure to show differential fear conditioning in the fronto-amygdala circuitry and impairment in extinction learning was specific to anxious youth. These findings expand our ability to track anxiety-related alterations and potential resilience markers to anxiety.

Mechanisms linking childhood adversity with psychopathology: Learning as an intervention target

Exposure to childhood adversity is common and a powerful risk factor for many forms of psychopathology. In this opinion piece, we argue for greater translation of knowledge about the developmental processes that are influenced by childhood adversity into targeted interventions to prevent the onset of psychopathology. Existing evidence has consistently identified several neurodevelopmental pathways that serve as mechanisms linking adversity with psychopathology. We highlight three domains in which these mechanisms are well-established and point to clear targets for intervention: 1) threat-related social information processing biases; 2) heightened emotional reactivity and difficulties with emotion regulation; and 3) disruptions in reward processing. In contrast to these established pathways, knowledge of how childhood adversity influences emotional learning mechanisms, including fear and reward learning, is remarkably limited. We see the investigation of these mechanisms as a critical next step for the field that will not only advance understanding of developmental pathways linking childhood adversity with psychopathology, but also provide clear targets for behavioral interventions. Knowledge of the mechanisms linking childhood adversity with psychopathology has advanced rapidly, and the time has come to translate that knowledge into clinical interventions to prevent the onset of mental health problems in children who have experienced adversity.

Chronic harsh parenting and anxiety associations with fear circuitry function in healthy adolescents: A preliminary study

Previous studies have reported altered fear circuitry function during fear conditioning in highly anxious individuals and in adults with a history of severe childhood adversity; less is known regarding younger populations and more common forms of adversity. We investigated fear circuitry functioning in healthy youths with histories of high (HH) or low (LH) chronic harsh parenting and high (HA) or low (LA) anxiety levels. 84 youths aged 13-16 performed an fMRI fear conditioning task. HH displayed decreased selective medial temporal lobe deactivations to CS+> CS- relative to LH. In addition, we found less amygdala-insula connectivity in HH vs LH. Interestingly, we observed distinct patterns of anxiety differences in amygdala-rostral ACC connectivity and subjective fear ratings depending on harsh parenting levels, suggesting a history of harsh parenting is linked with unique neural and behavioral anxious manifestations, which are different from anxiety manifestations in a context of low adversity.

Enhancing Inhibitory Learning: The Utility of Variability in Exposure

Exposure therapy has strong empirical support as a treatment for anxiety and related disorders, yet not all participants see clinically meaningful reduction in symptoms, and some experience return of fear. In this review, we examine the theoretical models of exposure therapy, from early precursors to the contemporary inhibitory learning model. The inhibitory learning model is applied to examine one potential method of improving outcomes in exposure therapy: increasing variability in the progression of the exposure hierarchy. We explore mechanisms that support the use of variability in exposure, including the violation of expectancies to enhance learning. In addition, the role of intolerance of uncertainty in anxiety is examined; variable exposure therapy could target this transdiagnostic mechanism in anxiety and related disorders. Suggestions for future research are then offered.

Threat-related disorders as persistent motivational states of defense

Defensive motivation, broadly defined as the orchestrated optimization of defensive functions, encapsulates core components of threat-related psychopathology. The exact relationship between defensive functions and stress-induced symptoms, however, is not entirely clear. Here we review how some of the most important behavioral and neurological findings related to threat-related disorders -- lowering response threshold to threats, facilitated learning and generalization to new threatening cues, reduced appetitive sensitivity, and resistance to extinction of the defensive state -- map onto defensive motivational states, highlighting evidence that supports conjecturing threat-related disorders as persistent motivational states. We propose a mechanism for the perpetuation of the motivational state, progressively converting temporary defensive functions into persistent defensive states associated with distress and impairment.

Behavioral interventions to eliminate fear responses

Fear memory underlies anxiety-related disorders, including posttraumatic stress disorder (PTSD). PTSD is a fear-based disorder, characterized by difficulties in extinguishing the learned fear response and maintaining extinction. Currently, the first-line treatment for PTSD is exposure therapy, which forms an extinction memory to compete with the original fear memory. However, the extinguished fear often returns under numerous circumstances, suggesting that novel methods are needed to eliminate fear memory or facilitate extinction memory. This review discusses research that targeted extinction and reconsolidation to manipulate fear memory. Recent studies indicate that sleep is an active state that can regulate memory processes. We also discuss the influence of sleep on fear memory. For each manipulation, we briefly summarize the neural mechanisms that have been identified in human studies. Finally, we highlight potential limitations and future directions in the field to better translate existing interventions to clinical settings.

An Inhibitory Learning Approach to Cognitive-Behavioral Therapy for Children and Adolescents

Although exposure-based cognitive-behavioral therapy (CBT) is efficacious for childhood anxiety and obsessive-compulsive disorder (OCD), many youth do not adequately respond to treatment. Extinction learning is an important process in exposure-based CBT. However, youth with anxiety disorders and OCD exhibit impairments in extinction processes that are best characterized by deficits in inhibitory learning. Therefore, the utilization of strategies to optimize inhibitory learning during exposures may compensate for these deficits, thereby maximizing extinction processes and producing more robust treatment outcomes for exposure-based CBT. This paper reviews several strategies to optimize inhibitory learning in youth with anxiety disorders and OCD, and presents practical examples for each strategy. This paper also highlights the difference between inhibitory learning-based exposures and prior conceptual approaches to exposure therapy in clinical practice. It concludes with a discussion of future directions for clinical research on inhibitory learning and exposure-based CBT in youth.

Impact of Gender on Child and Adolescent PTSD

PURPOSE OF REVIEW

This review examines the recent literature on biological factors that influence sex differences in posttraumatic stress disorder (PTSD) during childhood and adolescence, focusing on neurobiological, hormonal, and genetic factors that may increase risk in girls.

RECENT FINDINGS

More than 60% of children and adolescents are exposed to traumatic events, and many develop PTSD. There is increasing recognition of gender differences in PTSD, with women having double the rates of the disorder compared to men. These gender differences in symptoms and their underlying neurobiology appear to emerge during adolescence, although it is still unclear which biological mechanisms may play key roles in the development of sex difference. The literature on gender effects in children and adolescents is still in the early stages, and more prospective and longitudinal work is needed; however, estrogen appears to play a key role in increasing risk for PTSD in girls, which emerges in adolescence.

Using the research domain criteria (RDoC) to conceptualize impulsivity and compulsivity in relation to addiction

Nomenclature for mental disorder was updated in 2013 with the publication of the fifth edition of the Diagnostic and Statistical Manual (DSM-5). In DSM-5, substance use disorders are framed as more dimensional. First, the distinction between abuse and dependence is replaced by substance use. Second, the addictions section now covers both substances and behavioral addictions. This contemporary move toward dimensionality and transdiagnosis in the addictions and other disorders embrace accumulating cognitive-affective neurobiological evidence that is reflected in the United States' National Institutes of Health Research Domain Criteria (NIH RDoC). The RDoC calls for the further development of transdiagnostic approaches to psychopathy and includes five domains to improve research. Additionally, the RDoC suggests that these domains can be measured in terms of specific units of analysis. In line with these suggestions, recent publications have stimulated updated neurobiological conceptualizations of two transdiagnostic concepts, namely impulsivity and compulsivity and their interactions that are applicable to addictive disorders. However, there has not yet been a review to examine the constructs of impulsivity and compulsivity in relation to addiction in light of the research-oriented RDoC. By doing so it may become clearer as to whether impulsivity and compulsivity function antagonistically, complementarily or in some other way at the behavioral, cognitive, and neural level and how this relationship underpins addiction. Thus, here we consider research into impulsivity and compulsivity in light of the transdiagnostic RDoC to help better understand these concepts and their application to evidence-based clinical intervention for addiction.