Interfacing neural constructs with the Hierarchical Taxonomy of Psychopathology: 'Why' and 'how'

Triarchic traits as risk versus protective factors for ADHD symptomatology: A prospective longitudinal investigation

Attention-deficit/hyperactivity disorder (ADHD) symptoms are associated with myriad adverse outcomes, including interpersonal difficulties, but factors that moderate the developmental course and functional impact of ADHD over time are not well understood. The present study evaluated developmental contributions of the triarchic neurobehavioral traits (boldness, meanness, and disinhibition) to ADHD symptomatology and its subdimensions from adolescence to young adulthood. Participants were twins and triplets assessed at ages 14, 17, and 19 (initial N = 1,185, 51.2% female). Path analyses using negative binomial regression revealed that boldness at age 14 was associated with more ADHD symptoms cross-sectionally (especially hyperactivity/impulsivity), but fewer symptoms (especially inattention) at age 19 in the prospective analysis. Notably, inclusion of interpersonal problems at ages 14 and 17 as covariates reduced the latter effect to nonsignificant. Disinhibition concurrently and prospectively predicted higher levels of ADHD symptoms, including both subdimensions, and the prospective effects were partially mediated by greater social impairment at age 17. Meanness prospectively (but not concurrently) predicted higher levels of hyperactivity/impulsivity symptoms. Sex moderated certain associations of meanness and disinhibition with ADHD symptoms. These findings highlight how fundamental neurobehavioral traits shape both psychopathology and adaptive outcomes in the developmental course of ADHD.

Pathological personality dimensions and neurobiological emotional reactivity

BACKGROUND

The Hierarchical Taxonomy of Psychopathology (HiTOP) offers a promising framework to identify the neurobiological mechanisms of psychopathology. Many forms of psychopathology are characterized by dysfunctional emotional reactivity. The late positive potential (LPP) is an event-related potential component that provides an index of neurobiological emotional reactivity. Several categorical disorders have demonstrated a similar association with the emotion-modulated LPP. It is possible that higher-order dimensional representations of psychopathology might explain the comparable results. The present study examined the association between HiTOP-consistent pathological personality dimensions across multiple levels of the hierarchy and neurobiological emotional reactivity.

METHODS

The sample included 215 18-35-year-old adults (86% female) who were oversampled for psychopathology. Participants completed the emotional interrupt task while electroencephalography was recorded to examine the LPP. Participants also completed the Comprehensive Assessment of Traits relevant to Personality Disorders to assess pathological personality.

RESULTS

At the spectra level, higher negative emotionality was associated with a larger emotion-modulated LPP, while higher detachment was associated with a smaller emotion-modulated LPP. There were no associations between higher-order psychopathology levels and the emotion-modulated LPP. Compared to categorical diagnoses, spectra-level personality pathology dimensions significantly improved the prediction of the emotion-modulated LPP.

CONCLUSIONS

The present study indicates that HiTOP spectra levels of negative emotionality and detachment demonstrate unique associations with neurobiological emotional reactivity. The study highlights the utility of examining dimensional and hierarchical, rather than categorical, representations of psychopathology in the attempt to identify the neurobiological origins of psychopathology.

Pathological personality domains and punishment-enhanced error-related negativity

The error-related negativity (ERN) is an event-related potential that is observed after the commission of an error and is hypothesized to index threat sensitivity. The ERN is associated with multiple psychiatric disorders, but it is unclear if similar results are due to higher-order dimensions of psychopathology. When errors are punished, the ERN is further enhanced, which might better isolate threat sensitivity. However, few studies have examined whether psychopathology is associated with punishment enhancement of the ERN. In a clinical sample of 170 adults, the present study examined the association between pathological personality domains and predictable vs. unpredictable punishment-enhanced ERN. Results indicated that the ERN was enhanced when errors were punished compared to not punished. Greater negative emotionality was associated with a greater predictable punishment-enhanced ERN, while greater disinhibition was associated with smaller predictable punishment-enhanced ERN. The study suggests that higher-order pathological personality domains demonstrate discriminate relationships with punishment-enhanced error-related brain activity.

Transdiagnostic psychopathology in the light of robust single-trial event-related potentials

Recent evidence indicates that event-related potentials (ERPs) as measured on the electroencephalogram (EEG) are more closely related to transdiagnostic, dimensional measures of psychopathology (TDP) than to diagnostic categories. A comprehensive examination of correlations between well-studied ERPs and measures of TDP is called for. In this study, we recruited 50 patients with emotional disorders undergoing 14 weeks of transdiagnostic group psychotherapy as well as 37 healthy comparison subjects (HC) matched in age and sex. HCs were assessed once and patients three times throughout treatment (N = 172 data sets) with a battery of well-studied ERPs and psychopathology measures consistent with the TDP framework The Hierarchical Taxonomy of Psychopathology (HiTOP). ERPs were quantified using robust single-trial analysis (RSTA) methods and TDP correlations with linear regression models as implemented in the EEGLAB toolbox LIMO EEG. We found correlations at several levels of the HiTOP hierarchy. Among these, a reduced P3b was associated with the general p-factor. A reduced error-related negativity correlated strongly with worse symptomatology across the Internalizing spectrum. Increases in the correct-related negativity correlated with symptoms loading unto the Distress subfactor in the HiTOP. The Flanker N2 was related to specific symptoms of Intrusive Cognitions and Traumatic Re-experiencing and the mismatch negativity to maladaptive personality traits at the lowest levels of the HiTOP hierarchy. Our study highlights the advantages of RSTA methods and of using validated TDP constructs within a consistent framework. Future studies could utilize machine learning methods to predict TDP from a set of ERP features at the subject level.

Robust single-trial event-related potentials differentiate between distress and fear disorders

Recent evidence indicates that measures of brain functioning as indexed by event-related potentials (ERPs) on the electroencephalogram align more closely to transdiagnostic measures of psychopathology than to categorical taxonomies. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a transdiagnostic, dimensional framework aiming to solve issues of comorbidity, symptom heterogeneity, and arbitrary diagnostic boundaries. Based on shared features, the emotional disorders are allocated into subfactors Distress and Fear. Evidence indicates that disorders that are close in the HiTOP hierarchy share etiology, symptom profiles, and treatment outcomes. However, further studies testing the biological underpinnings of the HiTOP are called for. In this study, we assessed differences between Distress and Fear in a range of well-studied ERP components. In total, 50 patients with emotional disorders were divided into two groups (Distress, N = 25; Fear, N = 25) according to HiTOP criteria and compared against 37 healthy comparison (HC) subjects. Addressing issues in traditional ERP preprocessing and analysis methods, we applied robust single-trial analysis as implemented in the EEGLAB toolbox LIMO EEG. Several ERP components were found to differ between the groups. Surprisingly, we found no difference between Fear and HC for any of the ERPs. This suggests that some well-established results from the literature, e.g., increased error-related negativity in OCD, are not a shared neurobiological correlate of the Fear subfactor. Conversely, for Distress, we found reductions compared to Fear and HC in several ERP components across paradigms. Future studies could utilize HiTOP-validated psychopathology measures to more precisely define subfactor groups.

No relations between executive functions and dimensional models of psychopathology or is time the missing link?

Impaired executive functions (EF) have been found within various mental disorders (e.g., attention deficit hyperactivity disorder, autism spectrum disorder, schizophrenia spectrum disorders) as described in DSM-5. However, although impaired EF has been observed within several categories of mental disorders, empirical research on direct relations between EF and broader dimension of psychopathology is still scarce. Therefore, in the current investigation we examined relations between three EF performance tasks and self-reported dimensions of psychopathology (i.e., the internalizing, externalizing, and thought disorder spectra) in a combined dataset of patients with a broad range of mental disorders (N = 440). Despite previously reported results that indicate impaired EF in several categories of mental disorders, in this study no direct relations were found between EF performance tasks and self-reported broader dimensions of psychopathology. These results indicate that relations between EF and psychopathology could be more complex and non-linear in nature. We evaluate the need for integration of EF and dimensional models of psychopathology and reflect on EF as a possible transdiagnostic factor of psychopathology.

Examining associations between genetic and neural risk for externalizing behaviors in adolescence and early adulthood

BACKGROUND

Researchers have identified genetic and neural risk factors for externalizing behaviors. However, it has not yet been determined if genetic liability is conferred in part through associations with more proximal neurophysiological risk markers.

METHODS

Participants from the Collaborative Study on the Genetics of Alcoholism, a large, family-based study of alcohol use disorders were genotyped and polygenic scores for externalizing (EXT PGS) were calculated. Associations with target P3 amplitude from a visual oddball task (P3) and broad endorsement of externalizing behaviors (indexed via self-report of alcohol and cannabis use, and antisocial behavior) were assessed in participants of European (EA; N = 2851) and African ancestry (AA; N = 1402). Analyses were also stratified by age (adolescents, age 12-17 and young adults, age 18-32).

RESULTS

The EXT PGS was significantly associated with higher levels of externalizing behaviors among EA adolescents and young adults as well as AA young adults. P3 was inversely associated with externalizing behaviors among EA young adults. EXT PGS was not significantly associated with P3 amplitude and therefore, there was no evidence that P3 amplitude indirectly accounted for the association between EXT PGS and externalizing behaviors.

CONCLUSIONS

Both the EXT PGS and P3 amplitude were significantly associated with externalizing behaviors among EA young adults. However, these associations with externalizing behaviors appear to be independent of each other, suggesting that they may index different facets of externalizing.

Lateral prefrontal cortex thickness is associated with stress but not cognitive fatigue in exhaustion disorder

Introduction

Impaired executive functioning, including cognitive fatigue, is a core feature of the long-term stress-related condition exhaustion disorder (ED). Recent research suggests that a key area for executive control, the lateral prefrontal cortex (LPFC), may be mechanistically linked to cognitive fatigue due to stress. Here, we therefore asked if and how stress, the LPFC and cognitive fatigue may be related in ED.

Methods

We used a multimodal cross-sectional study design with high-resolution structural magnetic resonance imaging (MRI), self-reported measures, and path analysis modeling in 300 participants with ED.

Results

We found positive associations between stress and cognitive fatigue, and stress and LPFC thickness,but no association between LPFC thickness and cognitive fatigue. Furthermore, LPFC thickness did not mediate or moderate the association between stress and cognitive fatigue.

Discussion

These findings suggest that LPFC brain morphology is related to perceived stress levels but not cognitive fatigue, expanding previous research on the role of the LPFC in executive functioning. Moreover, the results support the notion that the LPFC may be mechanistically involved in stress-related executive function impairment but prompt further research into if and how this may be related to cognitive symptoms in ED.

Psychopathology in children: The transdiagnostic contribution of affiliative capacity and inhibitory control

Recent initiatives have focused on integrating transdiagnostic biobehavioral processes or dispositions with dimensional models of psychopathology. Toward this goal, biobehavioral traits of affiliative capacity (AFF) and inhibitory control (INH) hold particular promise as they demonstrate transdiagnostic stability and predictive validity across developmental stages and differing measurement modalities. The current study employed data from different modes of measurement in a sample of 1830 children aged 5-10 years to test for associations of AFF and INH, individually and interactively, with broad dimensions of psychopathology. Low AFF, assessed via parent-report, evidenced predictive relations with distress- and externalizing-related problems. INH as assessed by cognitive-task performance did not relate itself to either psychopathology dimension, but it moderated the effects observed for low AFF, such that high INH protected against distress symptoms in low-AFF participants, whereas low INH amplified distress and externalizing symptoms in low-AFF participants. Results are discussed in the context of the interface of general trait transdiagnostic risk factors with quantitatively derived dimensional models of psychopathology.

Precision behavioral phenotyping as a strategy for uncovering the biological correlates of psychopathology

Our capacity to measure diverse aspects of human biology has developed rapidly in the past decades, but the rate at which these techniques have generated insights into the biological correlates of psychopathology has lagged far behind. The slow progress is partly due to the poor sensitivity, specificity and replicability of many findings in the literature, which have in turn been attributed to small effect sizes, small sample sizes and inadequate statistical power. A commonly proposed solution is to focus on large, consortia-sized samples. Yet it is abundantly clear that increasing sample sizes will have a limited impact unless a more fundamental issue is addressed: the precision with which target behavioral phenotypes are measured. Here, we discuss challenges, outline several ways forward and provide worked examples to demonstrate key problems and potential solutions. A precision phenotyping approach can enhance the discovery and replicability of associations between biology and psychopathology.

Intolerance to uncertainty and self-efficacy as mediators between personality traits and adjustment disorder in the face of the COVID-19 pandemic

In April 2020, early in the COVID-19 outbreak, governments restricted public gatherings and ordered social distancing. These demands led to challenging adaptations, which in some cases resulted in mental health issues, including adjustment disorder. Guided by the transactional stress model, the current study aimed to examine the relations between personality traits and adjustment disorder in crisis situations and vagueness and the role of intolerance to uncertainty and self-efficacy in these relations. During Israel's first lockdown, 673 Israeli adults completed self-reported e-version questionnaires regarding Big Five personality traits, adjustment disorder, intolerance to uncertainty, self-efficacy, and background variables. The study was designed to examine the association between personality traits and adjustment disorder and the potential mediation of intolerance to uncertainty and self-efficacy in associations. The findings revealed that intolerance to uncertainty and self-efficacy mediated the association between personality traits and adjustment disorder. The results are consistent with the transactional stress model. They shed light on the role of intolerance to uncertainty and self-efficacy as cognitive mechanisms that promote the development of adjustment disorder. Recommendations for future studies and practice are discussed.

Situating Psychopathy Within the DSM-5 Alternative Model of Personality Disorders (AMPD) Among Italian Community-Dwelling Adults

Given growing evidence for a joint hierarchical framework of clinical and personality symptomatology, situating triarchic traits within this model would acknowledge transdiagnostic trait-related variance and provide a basis for linking the DSM-5 Alternative Model of Personality Disorders (AMPD) domains to established indicators of these neurobehavioral traits. The current study (N = 2,041 Italian adults) sought to replicate and extend recent evidence regarding the locations of triarchic traits within the AMPD and to examine relations with criterion measures at different levels of the hierarchy. "Bass-ackwards" analyses revealed a hierarchical structure of personality pathology in which triarchic traits aligned with broad dispositional domains of the AMPD. Boldness, meanness, and disinhibition were clearly situated within the Externalizing branch of the hierarchy and helped to differentiate the Negative Affect, Antagonism, Detachment, and Disinhibition domains at lower levels. The current findings support the view of psychopathy as multidimensional and encompassing developmentally meaningful and neurobehaviorally relevant traits.

Identifying latent profiles of emotion dysregulation in a sample of primarily Black women with trauma exposure

BACKGROUND

Emotion dysregulation (ED) is a heterogenous, multi-dimensional transdiagnostic risk factor relevant to the development and maintenance of both internalizing and externalizing psychopathology, especially for those who have experienced trauma. The goals of the current study were to use person-centered analyses to identify distinct profiles of individuals characterized by unique patterns of ED dimensions, and to examine differences in internalizing and externalizing symptoms in a community sample.

METHODS

Participants (n = 783, 97% Black, 93% women) were recruited from an urban safety net hospital with high rates of trauma exposure. Latent profile analysis was used to uncover unique patterns of ED and multinomial logistic regression to evaluate the conditional distribution of our correlates across profiles.

RESULTS

The best-fitting model uncovered four classes: Low ED (42%), Low Awareness/Clarity (34%), Low Impulse Control (17%), and High ED (6%). All classes differed in terms of internalizing symptoms (anxiety sensitivity, depression, PTSD), with classes characterized by higher ED reporting more severe symptoms. For externalizing symptoms (food addiction behaviors, alcohol and drug abuse, aggressive behavior), the Low ED class reported fewer symptoms than all other profiles, while Low Awareness/Clarity, Low Impulse Control, and High ED did not differ from each other.

CONCLUSIONS

Patterns of emotion dysregulation ought to be assessed and considered as treatment targets for those experiencing both internalizing and externalizing psychopathology symptoms.

A Hierarchical Taxonomy of Psychopathology (HiTOP) Primer for Mental Health Researchers

Mental health research is at an important crossroads as the field seeks more reliable and valid phenotypes to study. Dimensional approaches to quantifying mental illness operate outside the confines of traditional categorical diagnoses, and they are gaining traction as a way to advance research on the causes and consequences of mental illness. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a leading dimensional research paradigm that synthesizes decades of data on the major dimensions of psychological disorders. In this article, we demonstrate how to use the HiTOP model to formulate and test research questions through a series of tutorials. To boost accessibility, data and annotated code for each tutorial are included at OSF (https://osf.io/8myzw). After presenting the tutorials, we outline how investigators can use these ideas and tools to generate new insights in their own substantive research programs.

Depressive symptom complexes of community-dwelling older adults: a latent network model

Late-life depression has multiple, heterogeneous clinical presentations. The aim of the study was to identify higher-order homogeneous clinical features (symptom complexes), while accounting for their potential causal interactions within the network approach to psychopathology. We analyzed cross-sectional data from community-dwelling adults aged 65-85 years recruited by the European MentDis_ICF65+ study (n = 2623, mean age 74, 49% females). The severity of 33 depressive symptoms was derived from the age-adapted Composite International Diagnostic Interview. Symptom complexes were identified using multiple detection algorithms for symptom networks, and their fit to data was assessed with latent network models (LNMs) in exploratory and confirmatory analyses. Sensitivity analyses included the Partial Correlation Likelihood Test (PCLT) to investigate the data-generating structure. Depressive symptoms were organized by the Walktrap algorithm into eight symptom complexes, namely sadness/hopelessness, anhedonia/lack of energy, anxiety/irritability, self-reproach, disturbed sleep, agitation/increased appetite, concentration/decision making, and thoughts of death. An LNM adequately fit the distribution of individual symptoms' data in the population. The model suggested the presence of reciprocal interactions between the symptom complexes of sadness and anxiety, concentration and self-reproach and between self-reproach and thoughts of death. Results of the PCLT confirmed that symptom complex data were more likely generated by a network, rather than a latent-variable structure. In conclusion, late-life depressive symptoms are organized into eight interacting symptom complexes. Identification of the symptom complexes of late-life depression may streamline clinical assessment, provide targets for personalization of treatment, and aid the search for biomarkers and for predictors of outcomes of late-life depression.

Prolonged NoGo P3 latency as a possible neurobehavioral correlate of aggressive and antisocial behaviors: A Go/NoGo ERP study

Aggressive and antisocial behaviors are detrimental to society and constitute major challenges in forensic mental health settings, yet the associated neural circuitry remains poorly understood. Here, we investigated differences in aggressive and antisocial behaviors between healthy controls (n = 20) and violent mentally disordered offenders (MDOs; n = 26), and examined associations between aggressive and antisocial behaviors, behavioral inhibitory control, and neurophysiological activity across the whole sample (n = 46). Event-related potentials were obtained using EEG while participants completed a Go/NoGo response inhibition task, and aggressive and antisocial behaviors were assessed with the Life History of Aggression (LHA) instrument. Using a robust Bayesian linear regression approach, we found that MDOs scored substantially higher than healthy controls on LHA Aggression and Antisocial subscales. Using the whole sample and after adjusting for age, we found that scores on the LHA Aggression and Antisocial subscales were robustly associated with longer NoGo P3 latency, and less robustly with longer NoGo N2 latency. Post-hoc analyzes suggested that healthy controls and MDOs exhibited similar associations. With several limitations in mind, we suggest that prolonged NoGo P3 latency, reflecting decreased neural efficiency during the later stages of conflict monitoring or outcome evaluation, is a potential neurobehavioral correlate of aggressive and antisocial behaviors.

Machine learning approaches for parsing comorbidity/heterogeneity in antisociality and substance use disorders: A primer

By some accounts, as many as 93% of individuals diagnosed with antisocial personality disorder (ASPD) or psychopathy also meet criteria for some form of substance use disorder (SUD). This high level of comorbidity, combined with an overlapping biopsychosocial profile, and potentially interacting features, has made it difficult to delineate the shared/unique characteristics of each disorder. Moreover, while rarely acknowledged, both SUD and antisociality exist as highly heterogeneous disorders in need of more targeted parcellation. While emerging data-driven nosology for psychiatric disorders (e.g., Research Domain Criteria (RDoC), Hierarchical Taxonomy of Psychopathology (HiTOP)) offers the opportunity for a more systematic delineation of the externalizing spectrum, the interrogation of large, complex neuroimaging-based datasets may require data-driven approaches that are not yet widely employed in psychiatric neuroscience. With this in mind, the proposed article sets out to provide an introduction into machine learning methods for neuroimaging that can help parse comorbid, heterogeneous externalizing samples. The modest machine learning work conducted to date within the externalizing domain demonstrates the potential utility of the approach but remains highly nascent. Within the paper, we make suggestions for how future work can make use of machine learning methods, in combination with emerging psychiatric nosology systems, to further diagnostic and etiological understandings of the externalizing spectrum. Finally, we briefly consider some challenges that will need to be overcome to encourage further progress in the field.

From childhood maltreatment to adult inflammation: Evidence for the mediational status of social anxiety and low positive affect

Prior work has established a robust association between childhood maltreatment and systemic inflammatory activation later in life; however, the mechanisms involved in this process remain incompletely understood. The purpose of this investigation was to examine potential mechanistic roles for social anxiety (SA) symptoms and low positive affect (PA) in the path from childhood maltreatment to elevations in circulating interleukin (IL)-6, a common biomarker of inflammatory activation. In addition, building on prior work establishing linkages between mindful awareness and reductions in systemic inflammation, we examined the potential role of trait mindfulness as a moderator of the relationships among childhood maltreatment, SA, low PA, and IL-6. A serial mediation model utilizing a large epidemiologic dataset (final N ​= ​527) supported our central hypothesis that the direct effect of childhood maltreatment on IL-6 was fully serially statistically mediated by SA symptoms and low PA (but not high negative affect). Additionally, results indicated that individuals falling in the upper versus lower quartiles of SA symptoms demonstrated significantly elevated concentrations of IL-6, a finding that has not been previously reported. Trait mindfulness moderated the association between low PA and IL-6, to the exclusion of any paths related to negative affect. Additionally, results indicated that the effect of child maltreatment on IL-6 bypasses SA to indirectly impact IL-6 via negative affect. Overall, we conclude that childhood maltreatment and SA symptoms have a significant influence on IL-6, albeit indirectly via low PA, and the influence of PA on IL-6 may be uniquely susceptible to influence by individual differences in mindfulness.

Structural brain correlates of eating pathology symptom dimensions: A systematic review

There has been an increasing interest in neurobiological correlates of psychopathology with a growing consensus that such research questions are best investigated through dimensional approaches to psychopathology. One area that has been noticeably understudied in this regard is eating pathology. Therefore, the goal of the current systematic review was to summarize research on structural brain correlates of symptom dimensions of eating-related pathology. Google Scholar and PubMed databases were searched following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results suggest that restrained eating is associated with increased GMV (gray matter volume) in regions involved in emotional, visuo-spatial, attentional, and self-related processing. Disinhibitory eating is associated with increased GMV in regions involved in reward value of food-related stimuli and decreased GMV in regions involved in emotional/motivational processing. All told, results suggest that dimensions of eating pathology have differential neuroanatomical correlates potentially suggesting differences in neural pathways which has the potential to support future biologically-driven classification and treatment efforts.

Evaluating the criterion validity of hierarchical psychopathology dimensions across models: Familial aggregation and associations with research domain criteria (sub)constructs

The Hierarchical Taxonomy of Psychopathology (HiTOP) posits that psychopathology is a hierarchy of correlated dimensions. Numerous studies have examined the validity of these dimensions using bifactor models, in which each disorder loads onto both a general and specific factor (e.g., internalizing, externalizing). Although bifactor models tend to fit better than alternative models, concerns have been raised about bifactor model selection, factor reliability, and interpretability. Therefore, we compared the reliability and validity of several higher-order HiTOP dimensions between bifactor and correlated factor models using familial aggregation and associations with Research Domain Criteria (RDoC; sub)constructs as validators. Lifetime psychopathology was assessed in a community sample (N = 504) using dimensional disorder severity scales calculated from semistructured interview data. A series of unidimensional, correlated factor, and bifactor models were fit to model several HiTOP dimensions. A bifactor model with two specific factors (internalizing and disinhibited externalizing) and a correlated two-factor model provided the best fit to the data. HiTOP dimensions had adequate reliability in the correlated factor model, but suboptimal reliability in the bifactor model. The disinhibited externalizing dimension was highly correlated across the two models and was familial, yet largely unrelated to RDoC (sub)constructs in both models. The internalizing dimension in the correlated factor model and the general factor in the bifactor model were highly correlated and had similar validity patterns, suggesting the general factor was largely redundant with the internalizing dimension in the correlated factor model. These findings support concerns about the interpretability of psychopathology dimensions in bifactor models. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The Monash Autism-ADHD genetics and neurodevelopment (MAGNET) project design and methodologies: a dimensional approach to understanding neurobiological and genetic aetiology

Background

ASD and ADHD are prevalent neurodevelopmental disorders that frequently co-occur and have strong evidence for a degree of shared genetic aetiology. Behavioural and neurocognitive heterogeneity in ASD and ADHD has hampered attempts to map the underlying genetics and neurobiology, predict intervention response, and improve diagnostic accuracy. Moving away from categorical conceptualisations of psychopathology to a dimensional approach is anticipated to facilitate discovery of data-driven clusters and enhance our understanding of the neurobiological and genetic aetiology of these conditions. The Monash Autism-ADHD genetics and neurodevelopment (MAGNET) project is one of the first large-scale, family-based studies to take a truly transdiagnostic approach to ASD and ADHD. Using a comprehensive phenotyping protocol capturing dimensional traits central to ASD and ADHD, the MAGNET project aims to identify data-driven clusters across ADHD-ASD spectra using deep phenotyping of symptoms and behaviours; investigate the degree of familiality for different dimensional ASD-ADHD phenotypes and clusters; and map the neurocognitive, brain imaging, and genetic correlates of these data-driven symptom-based clusters.

Methods

The MAGNET project will recruit 1,200 families with children who are either typically developing, or who display elevated ASD, ADHD, or ASD-ADHD traits, in addition to affected and unaffected biological siblings of probands, and parents. All children will be comprehensively phenotyped for behavioural symptoms, comorbidities, neurocognitive and neuroimaging traits and genetics.

Conclusion

The MAGNET project will be the first large-scale family study to take a transdiagnostic approach to ASD-ADHD, utilising deep phenotyping across behavioural, neurocognitive, brain imaging and genetic measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00457-3.

Neurobiology and the Hierarchical Taxonomy of Psychopathology: progress toward ontogenetically informed and clinically useful nosology

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical structural model of psychological symptoms formulated to improve the reliability and validity of clinical assessment. Neurobiology can inform assessments of early risk and intervention strategies, and the HiTOP model has greater potential to interface with neurobiological measures than traditional categorical diagnoses given its enhanced reliability. However, one complication is that observed biological correlates of clinical symptoms can reflect various factors, ranging from dispositional risk to consequences of psychopathology. In this paper, we argue that the HiTOP model provides an optimized framework for conducting research on the biological correlates of psychopathology from an ontogenetic perspective that distinguishes among indicators of liability, current symptoms, and consequences of illness. Through this approach, neurobiological research can contribute more effectively to identifying individuals at high dispositional risk, indexing treatment-related gains, and monitoring the consequences of mental illness, consistent with the aims of the HiTOP framework.


Structural Brain Correlates of the Externalizing Spectrum in Young Adults

The externalizing spectrum, including traits and behaviors such as aggression, reduced inhibitiory control and substance abuse, is associated with altered prefrontal brain morphology. However, the degree to which different manifestations of the externalizing spectrum are associated with distinct or overlapping variations in individual brain morphology is unclear. Here, we therefore used structural magnetic resonance imaging, self-report assessment, and a response inhibition task in a sample of 59 young adults to examine how cortical thickness in the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), and dorsolateral prefrontal cortex (DLPFC) relate to four different manifestations of the externalizing spectrum: disinhibition, callous aggression, substance abuse, and behavioral inhibitory control. Using Bayesian linear regression models controlling for age, gender, and years of education, we found that the different manifestations of the externalizing spectrum were associated with both distinct and overlapping morphology variations. Specifically, both callous aggression and inhibitory control was associated with increased cortical thickness of the OFC, a region involved in reward processing, decision-making, and regulation of anxiety and fear. Both disinhibition and substance abuse were associated with DLPFC thickness, although with opposite association patterns, possibly reflecting processes related to inhibitory control, working memory and attention. Moreover, disinhibition, but not callous aggression or substance abuse, was associated with behavioral inhibitory control. Our results provide further support for the link between externalizing behaviors and prefrontal brain morphology, while identifying distinct prefrontal areas associated with different clinically relevant manifestations. These findings may help guide further research aimed at developing novel treatment and intervention strategies for externalizing behaviors and disorders.

Toward a multimodal measurement model for the neurobehavioral trait of affiliative capacity

A growing body of research supports the value of a multimodal assessment approach, drawing on measures from different response modalities, for clarifying how core biobehavioral processes relate to various clinical problems and dimensions of psychopathology. Using data for 507 healthy adults, the current study was undertaken to integrate self-report and neurophysiological (brain potential) measures as a step toward a multimodal measurement model for the trait of affiliative capacity (AFF) - a biobehavioral construct relevant to adaptive and maladaptive social-interpersonal functioning. Individuals low in AFF exhibit a lack of interpersonal connectedness, deficient empathy, and an exploitative-aggressive social style that may be expressed transdiagnostically in antagonistic externalizing or distress psychopathology. Specific aims were to (1) integrate trait scale and brain potential indicators into a multimodal measure of AFF and (2) evaluate associations of this multimodal measure with criterion variables of different types. Results demonstrated (1) success in creating a multimodal measure of AFF from self-report and neural indicators, (2) effectiveness of this measure in predicting both clinical-diagnostic and neurophysiological criterion variables, and (3) transdiagnostic utility of the multimodal measure at both specific-disorder and broad symptom-dimension levels. Our findings further illustrate the value of psychoneurometric operationalizations of biobehavioral trait dimensions as referents for clarifying transdiagnostic relationships between biological systems variables and empirically defined dimensions of psychopathology.

The difference between trait disinhibition and impulsivity-and why it matters for clinical psychological science

In the psychological science field, there is substantial interest in quantifying individual differences in self-regulatory capacity because of its transdiagnostic relevance to various forms of psychopathology. Trait disinhibition and impulsiveness are popular conceptualizations of dispositions reflecting self-regulation of behavioral and emotional responding. In the literature, these constructs are often treated interchangeably because of their shared focus on general disconstraint and a lack of direct comparisons between measures of each. The current work used structural modeling to examine conceptual and empirical differences between 2 popular operationalizations of these traits in 2 samples (Ns = 400, 308), and employed regression and dominance analyses to compare their predictive relations with criterion measures of externalizing problems and negative affectivity (NA). Impulsigenic traits were related both to externalizing problems and NA, whereas trait disinhibition was selectively associated with externalizing. In a dominance analysis, trait disinhibition exhibited complete dominance over all impulsigenic traits in predicting externalizing problems. Conversely, multiple impulsigenic traits evidenced complete dominance over trait disinhibition in prediction of NA. The current work provides evidence that (a) disinhibition and impulsigenic traits are not interchangeable, (b) disinhibition specifically indexes propensity for externalizing problems, and (c) impulsigenic traits reflect a blend of externalizing and NA that appears relevant to diverse forms of psychopathology. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A Model-Based Strategy for Interfacing Traits of the DSM-5 AMPD With Neurobiology

The DSM-5 alternative model for personality disorders (AMPD) groups traits into domains based on factor analyses of self-report data. AMPD traits may need to be configured differently to interface with neurobiology. Focusing on biobehavioral risk for externalizing problems in 334 adults, the authors used structural modeling to evaluate how well alternative configurations of AMPD traits, operationalized using the Personality Inventory for DSM-5 (PID-5), interface with neural indicators of externalizing liability. A model specifying two correlated factors defined by traits within the PID-5 Disinhibition domain and brain-response indicators of externalizing proneness exhibited inadequate fit. However, a model using PID-5 traits with better coverage of biobehavioral externalizing liability evidenced good fit. Scores on this PID-5 trait factor, termed "PID-5 Externalizing Proneness," converged well with criterion measures of externalizing proneness and diverged from measures of threat sensitivity. Findings illustrate how AMPD traits can be configured for use in investigations of biobehavioral risk for psychopathology.

Triarchic Neurobehavioral Correlates of Psychopathology in Young Children: Evidence from the Healthy Brain Network Initiative

Recent initiatives emphasize the need to consider developmental and transdiagnostic contributions of temperamental variation to psychopathological expression. Triarchic neurobehavioral trait dimensions (boldness, meanness, disinhibition), which demonstrate compatibility with established temperament models and can be quantified using items from different existing inventories, are well-suited to pursuing these goals. We undertook to develop item-based scales for indexing these traits in 285 children (ages 5-10) tested in the Child Mind Institute's Healthy Brain Network (HBN) study, and evaluated their psychometric properties in two separate samples of similar-aged children: 519 others from the HBN study and 261 for whom parental-informant ratings were obtained through MTurk. Associations with psychopathology measures provided evidence for a) transdiagnostic utility of the triarchic scales, b) (reversed) boldness as the strongest predictor of internalizing problems, c) meanness as related to both internalizing and externalizing problems, d) disinhibition as the strongest predictor of externalizing problems, and e)a moderating effect of meanness level on disinhibition's relationship with externalizing problems. This research demonstrates that the triarchic traits can be effectively represented in young children and show expected relations with clinical outcome measures. As such, this work provides a foundation for developmental research clarifying the role that core neurobehavioral dispositions play in mental health.

Negotiating a Medication Treatment Plan

As difficult as it may be for someone to decide to seek mental health care, following up with repeat appointments is more difficult. A common route to that first appointment is discharge from an emergency department or a first hospitalization following a mental health crisis. Best practice in discharge planning is establishing an appointment with an outpatient therapist. Key to establishing care with a mental health professional is building a relationship based on trust and compassion. Establishing that relationship takes time, yet the beginning of that process occurs in the initial appointment and negotiation of a plan of care that the client can commit to. This article focuses on the process of negotiating a plan of care that is collaboratively agreed upon and renegotiated as appropriate. When the plan of care is collaboratively developed, psychotherapy and pharmacotherapy adherence become non-issues because the client and provider have established trust and a clear path to achieve the desired goals. [Journal of Psychosocial Nursing and Mental Health Services, 58(9), 9-12.].

Posttraumatic stress symptomatology and abnormal neural responding during emotion regulation under cognitive demands: mediating effects of personality

Posttraumatic stress disorder (PTSD) is often complicated by the after-effects of mild traumatic brain injury (mTBI). The mixture of brain conditions results in abnormal affective and cognitive functioning, as well as maladaptive behavior. To better understand how brain activity explains cognitive and emotional processes in these conditions, we used an emotional N-back task and functional magnetic resonance imaging (fMRI) to study neural responses in US military veterans after deployments to Iraq and Afghanistan. Additionally, we sought to examine whether hierarchical dimensional models of maladaptive personality could account for the relationship between combat-related brain conditions and fMRI responses under cognitive and affective challenge. FMRI data, measures of PTSD symptomatology (PTSS), blast-induced mTBI (bmTBI) severity, and maladaptive personality (MMPI-2-RF) were gathered from 93 veterans. Brain regions central to emotion regulation were selected for analysis, and consisted of bilateral amygdala, bilateral dorsolateral prefrontal (dlPFC), and ventromedial prefrontal/subgenual anterior cingulate (vmPFC-sgACC). Cognitive load increased activity in dlPFC and reduced activity in emotional responding brain regions. However, individuals with greater PTSS showed blunted deactivations in bilateral amygdala and vmPFC-sgACC, and weaker responses in right dlPFC. Additionally, we found that elevated emotional/internalizing dysfunction (EID), specifically low positive emotionality (RC2), accounted for PTSS-related changes in bilateral amygdala under increased cognitive load. Findings suggest that PTSS might result in amygdala and vmPFC-sgACC activity resistant to moderation by cognitive demands, reflecting emotion dysregulation despite a need to marshal cognitive resources. Anhedonia may be an important target for interventions that improve the affective and cognitive functioning of individuals with PTSD.