Unique versus shared neural correlates of externalizing psychopathology in late childhood

Abstract

Childhood externalizing psychopathology is heterogeneous. Symptom variability in conduct disorder (CD), oppositional defiant disorder (ODD), attention-deficit/hyperactivity disorder (ADHD), and callous-unemotional (CU) traits designate different subgroups of children with externalizing problems who have specific treatment needs. However, CD, ODD, ADHD, and CU traits are highly comorbid. Studies need to generate insights into shared versus unique risk mechanisms, including through the use of functional magnetic resonance imaging (fMRI). In this study, we tested whether symptoms of CD, ODD, ADHD, and CU traits were best represented within a bifactor framework, simultaneously modeling shared (i.e., general externalizing problems) and unique (i.e., symptom-specific) variance, or through a four-correlated factor or second-order factor model. Participants (N = 11,878, age, M = 9 years) were from the Adolescent Brain and Cognitive Development Study. We used questionnaire and functional magnetic resonance imaging data (emotional N-back task) from the baseline assessment. A bifactor model specifying a general externalizing and specific CD, ODD, ADHD, and CU traits factors demonstrated the best fit. The four-correlated and second-order factor models both fit the data well and were retained for analyses. Across models, reduced right amygdala activity to fearful faces was associated with more general externalizing problems and reduced dorsolateral prefrontal cortex activity to fearful faces was associated with higher CU traits. ADHD scores were related to greater right nucleus accumbens activation to fearful and happy faces. Results give insights into risk mechanisms underlying comorbidity and heterogeneity within externalizing psychopathology. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Figure 1.

Bifactor model of attention-deficit/hyperactivity, oppositional defiance, conduct problems, and CU traits Note Model fit: χ²(433)= 4,448.83; CFI=.98; TLI=.98; RMSEA=.03. See Table S5 for individual item-factor loadings. *For the bifactor model one item loaded negatively on the specific ODD factor and was removed (“Disobedient at school”). ADHD=Attention-Deficit/Hyperactivity Disorder Specific Factor; CD=Conduct Disorder Specific Factor; CU=Callous-unemotional traits Specific Factor; ODD= Oppositional-Defiance Disorder Specific Factor.

Figure 2.

Differential associations between general externalizing, specific attention-deficit/hyperactivity, oppositional defiance, conduct problems, and CU traits, scores and neural activation in the right and left hemispheres during emotion processing of fearful faces versus neutral faces Note. Standardized estimates from the correlated dependent variable models of brain-behavior associations for fearful versus neutral contrast for both hemispheres. Models controlled for age, sex, income, minoritized status, and task accuracy (Table S9). ACC=anterior cingulate cortex; CU=Callous-unemotional; dlPFC=Dorsolateral Prefrontal Cortex; G= General Externalizing Factor; NAc=Nucleus Accumbens; OFC=Orbitofrontal Cortex; STG=Superior Temporal Gyrus. *p<.05 following FDR correction

Figure 3.

Differential associations between general externalizing, specific attention-deficit/hyperactivity, oppositional defiance, conduct problems, and CU traits, scores and neural activation in the right and left hemispheres during emotion processing of happy faces versus neutral faces Note. Standardized estimates from the correlated dependent variable models of brain-behavior associations for fearful versus neutral contrast for the both hemispheres. Models controlled for age, sex, income, minoritized status, and task accuracy (Table S9). ACC=anterior cingulate cortex; CU=Callous-unemotional; dlPFC=Dorsolateral Prefrontal Cortex; G=General Externalizing Factor; NAc=Nucleus Accumbens; OFC=Orbitofrontal Cortex; STG=Superior Temporal Gyrus. *p<.05, **p<.01 following FDR correction