Common genetic influences on negative emotionality and a general psychopathology factor in childhood and adolescence

Does shared genetic risk contribute to the co-occurrence of eating disorders and suicidality?

OBJECTIVE

There is a high level of co-occurrence of suicidality with eating disorders (EDs) but the reason for this is unknown. To test the hypothesis that suicidality and EDs share genetic risk contributing to the expression of both phenotypes.

METHOD

Female twins (N = 1,002) from the Australian Twin Registry, aged 28-40 years, were interviewed with diagnostic interviews. Lifetime diagnostic information relating to eating disorders [anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder, and purging disorder (PD)], suicidality (ranging transitory thoughts to suicide attempts), and major depression.

RESULTS

Any suicidal thoughts were reported by 24% of the sample, but prevalence of lifetime suicidality among female twins with EDs was much higher (43%), presence of an ED diagnosis more than doubling likelihood of suicidality (OR = 2.32, 95% CI: 1.63-3.31). AN and BN conveyed greatest risk of suicidality (OR = 2.03, 95% CI: 1.06-3.87; OR = 3.97, 95% CI: 2.01-7.85, respectively). Twin phenotype correlations showed monozygotic twins had uniformly higher estimates than dizygotic counterparts. A trivariate Cholesky model indicated a common genetic influence on suicidality and ED phenotypes (but not depression), and no nonshared environmental source.

DISCUSSION

Both cross twin phenotypic correlations and genetic modeling infer a common genetic pathway for suicidality and EDs, but further investigation is needed to elucidate whether this may constitute emotional dysregulation or other temperament-linked factors. Study findings also indicate that ED clients must be routinely assessed for presence of suicidality, independent of depression status.

Multi-atlas learner fusion: An efficient segmentation approach for large-scale data

We propose multi-atlas learner fusion (MLF), a framework for rapidly and accurately replicating the highly accurate, yet computationally expensive, multi-atlas segmentation framework based on fusing local learners. In the largest whole-brain multi-atlas study yet reported, multi-atlas segmentations are estimated for a training set of 3464 MR brain images. Using these multi-atlas estimates we (1) estimate a low-dimensional representation for selecting locally appropriate example images, and (2) build AdaBoost learners that map a weak initial segmentation to the multi-atlas segmentation result. Thus, to segment a new target image we project the image into the low-dimensional space, construct a weak initial segmentation, and fuse the trained, locally selected, learners. The MLF framework cuts the runtime on a modern computer from 36 h down to 3-8 min - a 270× speedup - by completely bypassing the need for deformable atlas-target registrations. Additionally, we (1) describe a technique for optimizing the weak initial segmentation and the AdaBoost learning parameters, (2) quantify the ability to replicate the multi-atlas result with mean accuracies approaching the multi-atlas intra-subject reproducibility on a testing set of 380 images, (3) demonstrate significant increases in the reproducibility of intra-subject segmentations when compared to a state-of-the-art multi-atlas framework on a separate reproducibility dataset, (4) show that under the MLF framework the large-scale data model significantly improve the segmentation over the small-scale model under the MLF framework, and (5) indicate that the MLF framework has comparable performance as state-of-the-art multi-atlas segmentation algorithms without using non-local information.

Mental disorders and risk of suicide attempt: a national prospective study

Most mental disorders, when examined independently, are associated with an elevated risk for suicide attempt. However, mental disorders often co-occur, and that co-occurrence is well explained by models where specific mental disorders are understood as manifestations of latent dimensions of psychopathology. To date, it remains unclear whether the risk of suicide attempt is due to specific mental disorders, to specific dimensions of psychopathology (that is, internalizing and externalizing dimensions), to a general psychopathology factor or to a combination of these explanations. In a large nationally representative prospective survey, the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), we used structural equation modeling to examine the shared and specific effects of Axis I and Axis II disorders on the occurrence of suicide attempts in the general population and among individuals with a lifetime history of suicidal ideation. Effects of mental disorders on the risk of suicide attempt were exerted almost exclusively through a general psychopathology factor representing the shared effect across all mental disorders. Effects of remitted psychiatric disorders on the risk of suicide attempt were fully mediated by current mental disorders. Similar patterns of associations were found in individuals with suicidal ideation. These results held when using different approaches to modeling psychiatric comorbidity. Our findings underscore the importance of adopting dimensional approaches to comorbidity in the study of suicidal behavior. Because mental disorders increase the risk of suicide attempt through a general psychopathology liability, this dimension should be considered as an important therapeutic target to substantially advance suicide prevention.

Adolescent emotionality and effortful control: Core latent constructs and links to psychopathology and functioning

Temperament is associated with important outcomes in adolescence, including academic and interpersonal functioning and psychopathology. Rothbart's temperament model is among the most well-studied and supported approaches to adolescent temperament, and contains 3 main components: positive emotionality (PE), negative emotionality (NE), and effortful control (EC). However, the latent factor structure of Rothbart's temperament measure for adolescents, the Early Adolescent Temperament Questionnaire Revised (EATQ-R; Ellis & Rothbart, 2001) has not been definitively established. To address this problem and investigate links between adolescent temperament and functioning, we used confirmatory factor analysis to examine the latent constructs of the EATQ-R in a large combined sample. For EC and NE, bifactor models consisting of a common factor plus specific factors for some subfacets of each component fit best, providing a more nuanced understanding of these temperament dimensions. The nature of the PE construct in the EATQ-R is less clear. Models replicated in a hold-out dataset. The common components of high NE and low EC where broadly associated with increased psychopathology symptoms, and poor interpersonal and school functioning, while specific components of NE were further associated with corresponding specific components of psychopathology. Further questioning the construct validity of PE as measured by the EATQ-R, PE factors did not correlate with construct validity measures in a way consistent with theories of PE. Bringing consistency to the way the EATQ-R is modeled and using purer latent variables has the potential to advance the field in understanding links between dimensions of temperament and important outcomes of adolescent development.

Criterion validity of the general factor of psychopathology in a prospective study of girls

BACKGROUND

The best-fitting model of the structure of common psychopathology often includes a general factor on which all dimensions of psychopathology load. Such a general factor would be important if it reflects etiologies and mechanisms shared by all dimensions of psychopathology. Nonetheless, a viable alternative explanation is that the general factor is partly or wholly a result of common method variance or other systematic measurement biases.

METHODS

To test this alternative explanation, we extracted general, externalizing, and internalizing factor scores using mother-reported symptoms across 5-11 years of age in confirmatory factor analyses of data from a representative longitudinal study of 2,450 girls. Independent associations between the three psychopathology factor scores and teacher-reported criterion variables were estimated in multiple regression, controlling intelligence, and demographic covariates.

RESULTS

The model including the general factor fit significantly better than a correlated two-factor (internalizing/externalizing) model. The general factor was robustly and independently associated with all measures of teacher-reported school functioning concurrently during childhood and prospectively during adolescence.

CONCLUSIONS

These findings weaken the hypothesis that the general factor of psychopathology in childhood is solely a measurement artifact and support further research on the substantive meaning of the general factor.

Factors of psychological distress: clinical value, measurement substance, and methodological artefacts

PURPOSE

Psychometric models and statistical techniques are cornerstones of research into latent structures of specific psychopathology and general mental health. We discuss "pivot points" for future research efforts from a psychometric epidemiology perspective, emphasising sampling and selection processes of both indicators that guide data collection as well as samples that are confronted with them.

METHOD

First, we discuss how a theoretical model of psychopathology determines which empirical indicators (questions, diagnoses, etc.) and modelling methods are appropriate to test its implications. Second, we deal with how different research designs introduce different (co-)variances between indicators, potentially leading to a different understanding of latent structures. Third, we discuss widening the range of statistical models available within the "psychometrics class": the inclusion of categorical approaches can help to enlighten the debate on the structure of psychopathology and agreement on a minimal set of models might lead to greater convergence between studies. Fourth, we deal with aspects of methodology that introduce spurious (co-)variance in latent structure analysis (response styles, clustered data) and differential item functioning to gather more detailed information and to guard against over-generalisation of results, which renders assessments unfair.

CONCLUSIONS

Building on established insights, future research efforts should be more explicit about their theoretical understanding of psychopathology and how the analysis of a given indicator-respondent set informs this theoretical model. A coherent treatment of theoretical assumptions, indicators, and samples holds the key to building a comprehensive account of the latent structures of different types of psychopathology and mental health in general.

Advancing understanding of executive function impairments and psychopathology: bridging the gap between clinical and cognitive approaches

Executive function (EF) is essential for successfully navigating nearly all of our daily activities. Of critical importance for clinical psychological science, EF impairments are associated with most forms of psychopathology. However, despite the proliferation of research on EF in clinical populations, with notable exceptions clinical and cognitive approaches to EF have remained largely independent, leading to failures to apply theoretical and methodological advances in one field to the other field and hindering progress. First, we review the current state of knowledge of EF impairments associated with psychopathology and limitations to the previous research in light of recent advances in understanding and measuring EF. Next, we offer concrete suggestions for improving EF assessment. Last, we suggest future directions, including integrating modern models of EF with state of the art, hierarchical models of dimensional psychopathology as well as translational implications of EF-informed research on clinical science.

Disorders without borders: current and future directions in the meta-structure of mental disorders

PURPOSE

Classification is the cornerstone of clinical diagnostic practice and research. However, the extant psychiatric classification systems are not well supported by research evidence. In particular, extensive comorbidity among putatively distinct disorders flags an urgent need for fundamental changes in how we conceptualize psychopathology. Over the past decade, research has coalesced on an empirically based model that suggests many common mental disorders are structured according to two correlated latent dimensions: internalizing and externalizing.

METHODS

We review and discuss the development of a dimensional-spectrum model which organizes mental disorders in an empirically based manner. We also touch upon changes in the DSM-5 and put forward recommendations for future research endeavors.

RESULTS

Our review highlights substantial empirical support for the empirically based internalizing-externalizing model of psychopathology, which provides a parsimonious means of addressing comorbidity.

CONCLUSIONS

As future research goals, we suggest that the field would benefit from: expanding the meta-structure of psychopathology to include additional disorders, development of empirically based thresholds, inclusion of a developmental perspective, and intertwining genomic and neuroscience dimensions with the empirical structure of psychopathology.

Transdiagnostic factors of psychopathology and substance use disorders: a review

PURPOSE

Research on the structure of mental disorders and comorbidity indicates that many forms of psychopathology and substance use disorders are manifestations of relatively few transdiagnostic latent factors. These factors have important consequences for mental disorder research and applied practice.

METHODS

We provide an overview of the transdiagnostic factor literature, with particular focus on recent advances.

RESULTS

Internalizing and externalizing transdiagnostic factors have been well characterized in terms of their structures, links with disorders, stability, and statistical properties (e.g., invariance and distributions). Research on additional transdiagnostic factors, such as thought disorder, is quickly advancing latent structural models, as are integrations of transdiagnostic constructs with personality traits. Genetically informed analyses continue to clarify the origins of transdiagnostic factor levels, and links between these factors and important environmental exposures provide promising new avenues of inquiry.

CONCLUSIONS

Transdiagnostic factors account for the development and continuity of disorders and comorbidity over time, function as the primary links between disorders and important outcomes such as suicide, mediate associations between environmental exposures and disorders, provide an empirically supported classification system, and serve as foci for efficient, broadband intervention approaches. Overall, transdiagnostic factor research indicates the paramount importance of understanding these constructs and, thereby, broadening our understanding of mental disorder in general.

Brief report: cognitive control helps explain comorbidity between alcohol use disorder and internalizing disorders

OBJECTIVE

Alcohol use and internalizing problems frequently co-occur. Cognitive control has been implicated in their etiology, but no studies have tested whether this construct helps explain the co-occurrence of these disorders.

METHOD

A total of 1,313 undergraduate students completed assessments of cognitive control, negative emotionality, and symptoms of alcohol use disorder (AUD), depression, and generalized anxiety disorder. Structural equation models examined the extent to which overlap between AUD and internalizing problems was explained by variance specific to cognitive control and negative emotionality, as well as variance shared by both constructs.

RESULTS

Symptoms of AUD and internalizing disorders were modestly correlated (depression: r = .16; anxiety: r = .14). Variance specific to cognitive control explained a significant proportion of the correlation between AUD and both depression and generalized anxiety (depression: 19%; generalized anxiety: 18%), as did variance common to cognitive control and negative emotionality (depression: 24%; generalized anxiety: 31%). Consistent with previous work, variance specific to negative emotionality also explained a large and statistically significant proportion of the correlation between AUD and internalizing disorder symptoms. Of note, the residualized correlation for AUD symptom endorsement with both depression and generalized anxiety problems was not statistically significant after accounting for both cognitive control and negative emotionality.

CONCLUSIONS

This study provides new evidence that cognitive control may help explain the overlap between AUD and internalizing disorders while further supporting the contribution of negative emotionality to this overlap. RESULTS have implications for intervention efforts aimed at reducing comorbid alcohol use disorder and internalizing disorders, as well as general psychopathology.

Comorbidity Among Dimensions of Childhood Psychopathology: Converging Evidence from Behavior Genetics

In this article, we review evidence from recent behavior genetic studies that examined the covariance among common childhood psychopathological conditions and tested specific hypotheses regarding common and broadband-specific underlying features of childhood psychopathology. Specifically, we review the distinction between internalizing and externalizing disorders, the support for the generalist genes and specialist environments model, negative emotionality as a heritable underlying feature common to both internalizing and externalizing disorders, and daring as a heritable broadband-specific underlying feature that distinguishes externalizing disorders from internalizing disorders. We also discuss the implications of research in the search for specific genes that influence childhood psychopathology and suggest avenues for new research.

A longitudinal examination of re-employment quality on internalizing symptoms and job-search intentions

Underemployed workers-those receiving less pay, working fewer hours, or using fewer skills than they would prefer-appear to experience negative mental health outcomes similar to the unemployed. Prior cross-sectional research provides mixed empirical evidence for this conclusion, however. The current study sought to clarify the impact of underemployment longitudinally, assessing mental health 5 times over 8 months after job loss. In addition to the commonly used indicators of underemployment, we designed a measure of cognitive complexity using the Occupational Information Network (O*NET), an extensive government database used to organize and categorize occupational information. Replicating past research, we found concurrent associations between all indexes of reemployment job quality and internalizing symptoms in the period immediately after reemployment. However, when controlling for quality of prior employment, all indicators except our measure for cognitive complexity became nonsignificant. As participants transitioned from unemployment to reemployment, only reductions in cognitive complexity were associated with sustained general internalizing symptoms. We also found that although changes in cognitive complexity had an immediate impact on the well-being of the recently reemployed, only the number of available weekly hours (full-time vs. part-time status) was relevant 6 to 12 weeks later. Our longitudinal model thus provides significant nuance to the current understanding of underemployment and mental health.

Viewing relational aggression through multiple lenses: Temperament, personality, and personality pathology

Dispositional trait frameworks offer great potential to elucidate the nature and development of psychopathology, including the construct of relational aggression. The present study sought to explore the dispositional context of relational aggression across three dispositional frameworks: temperament, personality, and personality pathology. Participants comprised a large community sample of youth, aged 6 to 18 years (N= 1,188; 51.2% female). Ratings of children's relational aggression, temperament, personality, and personality pathology traits were obtained through parent report (86.3% mothers). Results showed convergence and divergence across these three dispositional frameworks. Like other antisocial behavior subtypes, relational aggression generally showed connections with traits reflecting negative emotionality and poor self-regulation. Relational aggression showed stronger connections with temperament traits than with personality traits, suggesting that temperament frameworks may capture more relationally aggressive content. Findings at the lower order trait level help differentiate relational aggression from other externalizing problems by providing a more nuanced perspective (e.g., both sociabilityandshyness positively predicted relational aggression). In addition, there was little evidence of moderation of these associations by gender, age, or age2, and findings remained robust even after controlling for physical aggression. Results are discussed in the broader context of conceptualizing relational aggression in an overarching personality-psychopathology framework.

Longitudinal Prediction of the One-Year Course of Preschool ADHD Symptoms: Implications for Models of Temperament-ADHD Associations

Despite the fact that Attention-Deficit/Hyperactivity Disorder (ADHD) is often conceptualized as an extreme trait, there remains controversy about the best way to understand associations between temperament traits and ADHD. The current study examines longitudinal associations between temperament traits and ADHD during early childhood in order to critically examine vulnerability and spectrum models of trait-ADHD associations. Study participants were 109 children between the ages of 3 and 6 and their primary caregivers and teachers/daycare providers, community-recruited for ADHD-related problems. Primary caregivers completed the Kiddie Disruptive Behavior Disorders Schedule semi-structured diagnostic interview at the initial appointment and one year later. At the initial appointment, primary caregivers completed the Child Behavior Questionnaire as a measure of child temperament traits. Results from the initial time point indicated that high neuroticism and high surgency were associated with inattentive and hyperactive-impulsive ADHD symptoms, and low effortful control was associated with hyperactive-impulsive ADHD symptoms. However, none of these traits predicted the one-year course of ADHD symptoms. Results are more consistent with a spectrum (vs. vulnerability) model of trait-psychopathology associations, suggesting that traits, but may not influence longitudinal course during early childhood.

Frontal midline theta reflects anxiety and cognitive control: meta-analytic evidence

Evidence from imaging and anatomical studies suggests that the midcingulate cortex (MCC) is a dynamic hub lying at the interface of affect and cognition. In particular, this neural system appears to integrate information about conflict and punishment in order to optimize behavior in the face of action-outcome uncertainty. In a series of meta-analyses, we show how recent human electrophysiological research provides compelling evidence that frontal-midline theta signals reflecting MCC activity are moderated by anxiety and predict adaptive behavioral adjustments. These findings underscore the importance of frontal theta activity to a broad spectrum of control operations. We argue that frontal-midline theta provides a neurophysiologically plausible mechanism for optimally adjusting behavior to uncertainty, a hallmark of situations that elicit anxiety and demand cognitive control. These observations compel a new perspective on the mechanisms guiding motivated learning and behavior and provide a framework for understanding the role of the MCC in temperament and psychopathology.

Personality Traits Elucidate Sex Differences in Attention-Deficit/Hyperactivity Disorder Comorbidity During Early Childhood

Attention-Deficit/Hyperactivity Disorder (ADHD) is highly comorbid with other childhood disorders, and there are striking sex differences in this comorbidity, particularly during early childhood. For example, boys with ADHD are more likely to exhibit comorbid disruptive behavior and neurodevelopmental disorders, compared to girls, during early childhood. Yet, explanations for these well-established sex differences remain in short supply. The current study evaluated the novel hypothesis that personality traits may serve as intermediate phenotypes that help explain sex differences in common ADHD comorbidity profiles during early childhood. Study participants were 109 children between the ages of 3 and 6 and their primary caregivers and teachers/daycare providers, recruited from the community and over-recruited for ADHD-related problems. Primary caregivers completed the Child Behavior Checklist, and teachers/daycare providers completed the Teacher Report Form as a measure of child behavior problems. Examiners completed the California Q-Sort as a measure of child personality traits. Moderated mediation analyses suggested that personality traits explain associations between ADHD and oppositional-defiance, aggression, and language problems in a sex-specific manner. While high neuroticism mediated associations between ADHD and oppositional-defiance in girls, disagreeableness mediated associations between ADHD and aggression and low conscientiousness mediated associations between ADHD and neurodevelopmental language problems in boys. Sex differences in trait-psychopathology associations may help explain sex differences in comorbidity profiles with possible implications for child assessment and personalized early intervention.