The relationship between brain structure and general psychopathology in preadolescents

Categorical mental disorders are being recognized as suboptimal targets in clinical neuroscience due to poor reliability as well as high rates of heterogeneity within, and comorbidity between, mental disorders. As an alternative to the case-control approach, recent studies have focused on the relationship between neurobiology and latent dimensions of psychopathology. The current study aimed to investigate the relationship between brain structure and psychopathology in the critical preadolescent period when psychopathology is emerging. This study included baseline data from the Adolescent Brain and Cognitive Development (ABCD) Study® (n = 11,721; age range = 9-10 years; male = 52.2%). General psychopathology, externalizing, internalizing, and thought disorder dimensions were based on a higher-order model of psychopathology and estimated using Bayesian plausible values. Outcome variables included global and regional cortical volume, thickness, and surface area. Higher levels of psychopathology across all dimensions were associated with lower volume and surface area globally, as well as widespread and pervasive alterations across the majority of cortical and subcortical regions studied, after adjusting for sex, race/ethnicity, and parental education. The relationships between general psychopathology and brain structure were attenuated when adjusting for cognitive functioning. There was evidence of a relationship between externalizing psychopathology and frontal regions of the cortex that was independent of general psychopathology. The current study identified lower cortical volume and surface area as transdiagnostic biomarkers for general psychopathology in preadolescence. The widespread and pervasive relationships between general psychopathology and brain structure may reflect cognitive dysfunction that is a feature across a range of mental illnesses.