The Twin Study of Negative Valence Emotional Constructs

Pediatric assessment of Research Domain Criteria positive and negative valence systems: Partial genetic mediation of links to problem behaviors

We use the highly structured Laboratory-Temperament Assessment Battery to measure behaviors that map onto the Research Domain Criteria (RDoC) positive and negative valence systems. Using a birth record-based sample (N = 1374 individual twins; mean age 7.7 years), we created composites of observed behavior reflecting the RDoC constructs Reward Responsiveness, Frustrative Nonreward, Loss, and Fear. Next, we related the RDoC constructs concurrently and longitudinally to problem behaviors, measured using parent-report on the Health Behavior Questionnaire and symptom counts from the Diagnostic Interview Schedule for Children, Version IV (DISC-IV; reflecting DSM-IV). The four pediatric RDoC positive and negative valence system measures, especially Reward Responsiveness, Frustrative Nonreward, and Loss, were heritable and modestly but plausibly related to traditional DSM-based measures in a transdiagnostic manner. The modest predictions from RDoC measures to DSM-based measures were largely genetically mediated, although relationships with aggressive and oppositional behaviors were also influenced by common environmental factors. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Pediatric anxiety associated with altered facial emotion recognition

Multiple psychiatric disorders are associated with difficulties in facial emotion recognition. However, generalized anxiety disorder may be associated with more accurate recognition of others' emotional expressions, particularly expressions of happiness and fear, which index safety and threat. Children aged 9-14 from a community sample (N = 601) completed a facial emotion labeling task. Children's symptoms of depressive and anxiety syndromes were assessed by self- and parent-report. Elevated symptoms of generalized anxiety disorder were associated with more accurate facial emotion recognition (β = 0.16, p = 0.007), specifically recognition of happiness (β = 0.17, p = 0.002) and fear (β = 0.15, p = 0.006). Elevated depressive symptoms were associated with less accurate facial emotion recognition (β = -0.12, p = 0.018), specifically happiness (β = -0.15, p = 0.002). Elevated symptoms of separation anxiety disorder were also associated with less accurate facial emotion recognition (β = -0.16, p = 0.003), specifically happiness (β = -0.15, p = 0.006) and fear (β = -0.15, p = 0.005), which highlights the importance of distinguishing between anxiety syndromes. Results held when adjusting for child age and sex. Evidence that symptoms of generalized anxiety disorder are associated with more accurate recognition of happiness and fear is consistent with theories of heightened social vigilance and support a transdiagnostic role of facial emotion recognition that may inform the psychosocial development of youth with anxiety and depressive symptoms.

Children's Mental Health in Southwestern Ontario during Summer 2020 of the COVID-19 Pandemic

OBJECTIVE

COVID-19 presents an unprecedented global crisis. Research is critically needed to identify the impact of the pandemic on children's mental health including psychosocial factors that predict resilience, recovery, and persistent distress. The present study collected data in June-July 2020 to describe children's mental health during the initial phase of the pandemic, including the magnitude and nature of psychiatric and psychological distress in children, and to evaluate social support as a putative psychosocial moderator of children's increased distress.

METHOD

Children and parents from 190 families of children aged 8 to 13 from the Windsor-Essex region of Southwestern Ontario reported (i) retrospectively on children's well-being (e.g., worry, happiness) immediately prior to the pandemic and (ii) on children's current well-being; irritability; social support; and anxiety, depressive, and posttraumatic stress symptoms at the baseline assessment of an ongoing longitudinal study of the COVID-19 pandemic.

RESULTS

Children and parents reported worsened well-being and psychological distress during the pandemic compared to retrospective report of pre-pandemic well-being. Child-perceived social support from family and friends was associated with lower symptom severity and attenuated increase in psychological distress.

CONCLUSIONS

Study findings suggest possible broad psychological impacts of the COVID-19 pandemic and are consistent with prior research that indicates a protective role of social support to mitigate the negative psychological impact of the pandemic. These findings may inform clinical assessments and highlight the need for public resources to safeguard children's mental health.

Threat Conditioning and Trait-Based Vulnerability to Personality Disorder

Some personality disorders (PDs) are accompanied by heightened threat sensitivity to benign events, whereas others are associated with minimal reactivity to danger or punishment. Such aberrant patterns of defensive responding may be due to abnormal threat learning processes, analogous to those observed in other fear- and fearlessness-based disorders. We investigated threat learning deficits with a Pavlovian differential conditioning procedure in an undergraduate sample (n = 117) overselected for negative affectivity. Contrary to predictions, maladaptive personality traits, as assessed via the Personality Inventory for DSM-5, were largely unrelated to defensive responding (i.e., subjective and electrodermal reactions to danger and safety cues) during threat conditioning. We discuss the possible boundary conditions of threat learning abnormalities in PD and suggest research designs that could more effectively reveal such deficits, if they exist.

Genetic and environmental risk structure of internalizing psychopathology in youth

BACKGROUND

Internalizing disorders (IDs), consisting of syndromes of anxiety and depression, are common, debilitating conditions often beginning early in life. Various trait-like psychological constructs are associated with IDs. Our prior analysis identified a tripartite model of Fear/Anxiety, Dysphoria, and Positive Affect among symptoms of anxiety and depression and the following constructs in youth: anxiety sensitivity, fearfulness, behavioral activation and inhibition, irritability, neuroticism, and extraversion. The current study sought to elucidate their overarching latent genetic and environmental risk structure.

METHODS

The sample consisted of 768 juvenile twin subjects ages 9-14 assessed for the nine, abovementioned measures. We compared two multivariate twin models of this broad array of phenotypes.

RESULTS

A hypothesis-driven, common pathway twin model reflecting the tripartite structure of the measures were fit to these data. However, an alternative independent pathway model provided both a better fit and more nuanced insights into their underlying genetic and environmental risk factors.

CONCLUSIONS

Our findings suggest a complex latent genetic and environmental structure to ID phenotypes in youth. This structure, which incorporates both clinical symptoms and various psychological traits, informs future phenotypic approaches for identifying specific genetic and pathophysiological mechanisms underlying ID risk.

Genetic underpinnings of callous-unemotional traits and emotion recognition in children, adolescents, and emerging adults

BACKGROUND

Callous-Unemotional (CU) and psychopathic traits are consistently associated with impaired recognition of others' emotions, specifically fear and sadness. However, no studies have examined whether the association between CU traits and emotion recognition deficits is due primarily to genetic or environmental factors.

METHODS

The current study used data from 607 Caucasian twin pairs (N = 1,214 twins) to examine the phenotypic and genetic relationship between the Inventory of Callous-Unemotional Traits (ICU) and facial emotion recognition assessed via the laboratory-based Facial Expression Labeling Task (FELT).

RESULTS

The uncaring/callous dimension of the ICU was significantly associated with impaired recognition of happiness, sadness, fear, surprise, and disgust. The unemotional ICU dimension was significantly associated with improved recognition of surprise and disgust. Total ICU score was significantly associated with impaired recognition of sadness. Significant genetic correlations were found for uncaring/callous traits and distress cue recognition (i.e. fear and sadness). The observed relationship between uncaring/callous traits and deficits in distress cue recognition was accounted for entirely by shared genetic influences.

CONCLUSIONS

The results of the current study replicate previous findings demonstrating impaired emotion recognition among youth with elevated CU traits. We extend these findings by replicating them in an epidemiological sample not selected or enriched for pathological levels of CU traits. Furthermore, the current study is the first to investigate the genetic and environmental etiology of CU traits and emotion recognition, and results suggest genetic influences underlie the specific relationship between uncaring/callous traits and distress cue (fear/sadness) recognition in others.

The genetic and environmental structure of fear and anxiety in juvenile twins

Fear and anxiety are conceptualized as responses to acute or potential threat, respectively. Adult twin studies found substantial interplay between genetic and environmental factors influencing fear disorders (phobias) and anxiety disorders. Research in children, however, has largely examined these factors independently. Thus, there exists a substantial knowledge gap regarding the underlying etiologic structure of these closely-related constructs during development. Symptom counts for five fear (criticism, the unknown, death, animal, medical) and four anxiety (generalized, panic, separation, social) dimensions were obtained for 373 twin pairs ages 9-14. Multivariate twin modeling was performed to elucidate the genetic and environmental influences distributed amongst these dimensions. The best fitting model contained one genetic, two familial environmental, and two unique environmental factors shared between fear and anxiety symptoms plus dimension-specific genetic and unique environmental factors. Although several environmental factors were shared between fear and anxiety dimensions, one latent factor accounted for genetic influences across both domains. While adult studies find somewhat distinct etiological differences between anxiety and phobic disorders, the current results suggest that their relative genetic and environmental influences are not as clearly demarcated in children. These etiological distinctions are more nuanced, likely contributing to the highly diffuse symptom patterns seen during development.

The Genetic and Environmental Relationship Between Childhood Behavioral Inhibition and Preadolescent Anxiety

This study uses novel approaches to examine genetic and environmental influences shared between childhood behavioral inhibition (BI) and symptoms of preadolescent anxiety disorders. Three hundred and fifty-two twin pairs aged 9-13 and their mothers completed questionnaires about BI and anxiety symptoms. Biometrical twin modeling, including a direction-of-causation design, investigated genetic and environmental risk factors shared between BI and social, generalized, panic and separation anxiety. Social anxiety shared the greatest proportion of genetic (20%) and environmental (16%) variance with BI with tentative evidence for causality. Etiological factors underlying BI explained little of the risk associated with the other anxiety domains. Findings further clarify etiologic pathways between BI and anxiety disorder domains in children.

Fear-potentiated startle response as an endophenotype: Evaluating metrics and methods for genetic applications

The modulation of the startle response (SR) by threatening stimuli (fear-potentiated startle; FPS) is a proposed endophenotype for disorders of the fearful-fearlessness spectrum. FPS has failed to show evidence of heritability, raising concerns. However, metrics used to index FPS-and, importantly, other conditional phenotypes that are dependent on a baseline-may not be suitable for the approaches used in genetic epidemiology studies. Here, we evaluated multiple metrics of FPS in a population-based sample of preadolescent twins (N = 569 from 320 twin pairs, M_age = 11.4) who completed a fear-conditioning paradigm with airpuff-elicited SR on two occasions (~1 month apart). We applied univariate and multivariate biometric modeling to estimate the heritability of FPS using several proposed standardization procedures. This was extended with data simulations to evaluate biases in heritability estimates of FPS (and similar metrics) under various scenarios. Consistent with previous studies, results indicated moderate test-retest reliability (r = 0.59) and heritability of the overall SR (h² = 34%) but poor reliability and virtually no unique genetic influences on FPS when considering a raw or standardized differential score that removes baseline SR. Simulations demonstrated that the use of differential scores introduces bias in heritability estimates relative to jointly analyzing baseline SR and FPS in a multivariate model. However, strong dependency of FPS on baseline levels makes unique genetic influences virtually impossible to detect regardless of methodology. These findings indicate that FPS and other conditional phenotypes may not be well suited to serve as endophenotypes unless such codependency can be disentangled.

Confirmatory factor structure and psychometric properties of the Multidimensional Peer Victimization Scale

The Multidimensional Peer Victimization Scale (MPVS; Mynard & Joseph, 2000) is a 16-item self-report scale that captures peer victimization across four dimensions: physical victimization, verbal victimization, social manipulation, and attacks on property. Performance of the scale has not been evaluated among older adolescents. We examined the factor structure, internal consistency reliability, and performance of the scale in two separate epidemiological U.S. samples representing different age groups: 9-14 year olds (N=610) and 15-17 year olds (N=524). The four-factor structure of the scale was affirmed in both samples, however; there was not metric invariance by gender in the younger age group. The scale and its subscales were found to have good internal consistency. Expected relationships between the MPVS and measures of irritability, anxiety, and depression were affirmed. Results support continued use of the MPVS among child and adolescent samples.

A Developmental Twin Study of Emotion Recognition and Its Negative Affective Clinical Correlates

OBJECTIVE

Youth with psychiatric disorders distinguished by irritability, including depression and associated trait neuroticism, show deficits in the ability to recognize facial expressions of emotion, particularly happiness. However, the contribution of genetic and environmental factors to this ability remains unknown. The present study examined this trait in twins to assess the genetic and environmental influences on face-emotion recognition abilities and their association with irritability, neuroticism, and depression.

METHOD

Child and adolescent twins (N = 957 from 496 families) 9 to 17 years old rated their irritability (on the Affective Reactivity Index), neuroticism (on the Junior Eysenck Personality Questionnaire), and depression (on the Short Mood and Feelings Questionnaire) and completed a face-emotion labeling task. Faces depicting anger, disgust, fear, happiness, sadness, and surprise were morphed with a neutral face, yielding 10 levels of increasing emotional expressivity. Biometrical twin analyses evaluated contributions of genetic and environmental factors to the etiology of face-emotion recognition and its association with irritability, neuroticism, and depression.

RESULTS

Recognition of each emotion was heritable; common and specific sets of genetic factors influenced all emotions and individual emotions, respectively. Irritability, neuroticism, and depression were modestly and negatively correlated with emotion recognition, particularly the recognition of happiness. For irritability and neuroticism, this correlation appeared largely due to genetic factors.

CONCLUSION

This study maps genetic and environmental contributions to face-emotion recognition and its association with irritability, neuroticism, and depression. Findings implicate common genetic factors in deficits regarding the recognition of happiness associated with irritability and neuroticism in childhood and adolescence.

Age-Related Differences in the Structure of Genetic and Environmental Contributions to Types of Peer Victimization

The goal of the present investigation was to clarify and compare the structure of genetic and environmental influences on different types (e.g., physical, verbal) of peer victimization experienced by youth in pre-/early adolescence and mid-/late adolescence. Physical, verbal, social, and property-related peer victimization experiences were assessed in two twin samples (306 pairs, ages 9-14 and 294 pairs, ages 15-20). Cholesky decompositions of individual differences in victimization were conducted, and independent pathway (IP) and common pathway (CP) twin models were tested in each sample. In the younger sample, a Cholesky decomposition best described the structure of genetic and environmental contributors to peer victimization, with no evidence that common additive genetic or environmental factors influence different types of peer victimization. In the older sample, common environmental factors influenced peer victimization types via a general latent liability for peer victimization (i.e., a CP model). Whereas the pre-/early adolescent sample demonstrated no evidence of a shared genetic and environmental structure for different types of peer victimization, the mid-/late adolescent sample demonstrates the emergence of an environmentally-driven latent liability for peer victimization across peer victimization types.

A Population-Based Twin Study of Childhood Irritability and Internalizing Syndromes

Childhood irritability exhibits significant theoretical and empirical associations with depression and anxiety syndromes. The current study used the twin design to parse genetic and environmental contributions to these relationships. Children ages 9-14 from 374 twin pairs were assessed for irritability and symptoms of depression, generalized anxiety, panic, social phobia, and separation anxiety using dimensional self-report instruments. Multivariate structural equation modeling decomposed the correlations between these syndromes into genetic and environmental components to examine shared and specific risk domains. Irritability had significant associations with each internalizing symptom domain. Genetic contributions to irritability are moderately correlated with genetic risk for symptoms of depression, generalized anxiety, and separation anxiety with weaker overlap with the other anxiety syndromes. Familial and specific environmental risk factors explained covariation among syndromes and indicated potential syndrome-specific risk. There is substantial overlap among the genetic and environmental factors that influence individual differences in irritability and those that increase liability for depression and anxiety symptoms in children. These findings deepen the current understanding of childhood internalizing risk factors and provide important implications for syndrome prediction and susceptibility gene discovery efforts.

Genetic and Environmental Contributions of Negative Valence Systems to Internalizing Pathways

The genetic and environmental contributions of negative valence systems (NVS) to internalizing pathways study (also referred to as the Adolescent and Young Adult Twin Study) was designed to examine varying constructs of the NVS as they relate to the development of internalizing disorders from a genetically informed perspective. The goal of this study was to evaluate genetic and environmental contributions to potential psychiatric endophenotypes that contribute to internalizing psychopathology by studying adolescent and young adult twins longitudinally over a 2-year period. This report details the sample characteristics, study design, and methodology of this study. The first wave of data collection (i.e., time 1) is complete; the 2-year follow-up (i.e., time 2) is currently underway. A total of 430 twin pairs (N = 860 individual twins; 166 monozygotic pairs; 57.2% female) and 422 parents or legal guardians participated at time 1. Twin participants completed self-report surveys and participated in experimental paradigms to assess processes within the NVS. Additionally, parents completed surveys to report on themselves and their twin children. Findings from this study will help clarify the genetic and environmental influences of the NVS and their association with internalizing risk. The goal of this line of research is to develop methods for early internalizing disorder risk detection.

Test-retest reliability of the facial expression labeling task

Recognizing others' emotional expressions is vital for socioemotional development; impairments in this ability occur in several psychiatric disorders. Further study is needed to map the development of this ability and to evaluate its components as potential transdiagnostic endophenotypes. Before doing so, however, research is required to substantiate the test-retest reliability of scores of the face emotion identification tasks linked to developmental psychopathology. The current study estimated test-retest reliability of scores of one such task, the facial expression labeling task (FELT) among a sample of twin children (N = 157; ages 9-14). Participants completed the FELT at two visits two to five weeks apart. Participants discerned the emotion presented of faces depicting six emotions (i.e., happiness, anger, sadness, fear, surprise, and disgust) morphed with a neutral face to provide 10 levels of increasing emotional expressivity. The present study found strong test-retest reliability (Pearson r) of the FELT scores across all emotions. Results suggested that data from this task may be effectively analyzed using a latent growth curve model to estimate overall ability (i.e., intercept; r's = 0.76-0.85) and improvement as emotions become clearer (i.e., linear slope; r's = 0.69-0.83). Evidence of high test-retest reliability of this task's scores informs future developmental research and the potential identification of transdiagnostic endophenotypes for child psychopathology. (PsycINFO Database Record

Clinical Correlates of Carbon Dioxide Hypersensitivity in Children

OBJECTIVE

Hypersensitivity to carbon dioxide (CO₂)-enriched air may be a promising risk marker for anxiety disorders. Among adult and adolescent samples, heterogeneity in distress response to the CO₂ challenge task indexes 3 underlying classes of individuals, which distinguish between sustained and acute threat response as markers for internalizing disorders, broadly, and anxiety disorders, specifically. The present study examines latent classes in children's response to the CO₂ challenge task to clarify the association of CO₂ hypersensitivity with anxiety and internalizing symptomatology in childhood.

METHOD

Healthy children from a community twin sample (N = 538; age 9-13 years) rated anxious distress every 2 minutes while breathing air enriched to 7.5% CO₂ for 8 minutes. Latent growth mixture modeling evaluated potential classes of individuals with characteristic trajectories of distress during the task to clarify the association with internalizing disorder symptoms and related traits (e.g., anxiety sensitivity, irritability).

RESULTS

Although all participants reported increased distress during the task, interindividual heterogeneity in distress indexed 3 underlying classes: a consistently low class ("low"), a consistently high class ("high"), and participants who demonstrated markedly increased acute distress ("acute"). Compared to the low class, the high class reported greater internalizing psychopathology, whereas membership in the acute class was associated with experiencing a panic-like event during the task.

CONCLUSION

As in older individuals, 3 distinct trajectories emerged to capture interindividual heterogeneity in children's distress during the CO₂ challenge task. These classes were distinguished by clinical validators that reinforce the association of CO₂ hypersensitivity and internalizing disorder phenotypes in children.

Latent structure of negative valence measures in childhood

BACKGROUND

Internalizing disorders (IDs), consisting of the syndromes of anxiety and depression, are common, debilitating conditions often having onsets in adolescence. Scientists have developed dimensional self-report instruments that assess putative negative valence system (NVS) trait-like constructs as complimentary phenotypes to clinical symptoms. These include various measures that index temperamental predispositions to IDs and correlate with neural substrates of fear, anxiety, and affective regulation. This study sought to elucidate the overarching structure of putative NVS traits and their relationship to early manifestations of ID symptomatology.

METHODS

The sample consisted of 768 juvenile twin subjects ages 9-13. Together with ID symptoms, extant validated instruments were chosen to assess a broad spectrum of NVS traits: anxiety sensitivity, irritability, fearfulness, behavioral activation and inhibition, and neuroticism and extraversion. Exploratory and confirmatory factor analyses (EFA/CFA) were used to investigate the latent structure of the associations among these different constructs and ID symptoms. Bifactor modeling in addition to standard correlated-factor analytic approaches were applied.

RESULTS

Factor analyses produced a primary tripartite solution comprising anxiety/fear, dysphoria, and positive affect among all these measures. Competing DSM-like correlated factors and an RDoC-like NVS bifactor structure provided similar fit to these data.

CONCLUSIONS

Our findings support the conceptual organization of a tripartite latent internalizing domain in developing children. This structure includes both clinical symptoms and a variety of self-report dimensional traits currently in use by investigators. These various constructs are, therefore, most informatively investigated using an inclusive, integrated approach.

Test-retest reliability and validity of a frustration paradigm and irritability measures

BACKGROUND

Data on the reliability and validity of assessments for irritability, particularly behavioral paradigms, are limited. This study examined the test-retest reliability and validity of a frustration paradigm (the Affective Posner 2 task) and two irritability measures [the Affective Reactivity Index (ARI) and Child Behavior Checklist (CBCL) irritability].

METHODS

Participants were 109 youth from a general population sample of twins (aged 9-14 years). Participants completed two visits that were 2-4 weeks apart. At both visits, participants completed the Affective Posner 2 task and self-reported their irritability using the ARI. Parents reported their child's irritability using the ARI and completed the CBCL.

RESULTS

The Affective Posner 2 task demonstrated good test-retest reliability, with intraclass correlations (ICCs) ranging from .44 to .78. The task effectively evoked negative affect (frustration and unhappiness) at both test and retest, demonstrating its construct validity. Moreover, self-rated frustration and unhappiness during the frustration components of the task correlated positively with self-reported but not parent-reported irritability, providing modest support for convergent validity. Parent- and child-reports of the ARI and parent-reports of the CBCL irritability measure showed excellent test-retest reliability, with ICCs ranging from .88 to .90.

LIMITATIONS

The sample consists of mostly twins aged 9-14 years from the communities. Thus, results may not generalize to non-twin samples or clinical samples outside of this age range.

CONCLUSIONS

The Affective Posner 2 paradigm and the ARI and CBCL irritability scales may be useful tools for longitudinal or treatment research on irritability.

The Inventory of Callous-Unemotional Traits (ICU) in Children: Reliability and Heritability

Callous-unemotional (CU) traits comprise the core symptoms of psychopathy, yet no study has estimated the heritability of CU traits in a community sample of children using an instrument designed solely to assess CU traits. The current study uses data from 339 twin pairs aged 9-14 to examine the reliability and heritability of the parent-report Inventory of Callous-unemotional Traits (ICU) at two assessments approximately 3 weeks apart. Time-specific measurement error was taken into account to obtain a more accurate estimate of the heritability reflecting the latent liability to CU traits. Test-retest reliability was 0.84 and heritability at visit 1 was 39%. The heritability of the latent liability to CU traits was 47%. This latent liability contributed 79% of the variance in ICU score at visit 1 and visit 2. This is the first study to account for measurement error while examining the heritability of CU traits, furthering our understanding of psychopathy in children.