Clarifying the place of p300 in the empirical structure of psychopathology over development.

Psychophysiology can help elucidate the structure and developmental mechanisms of psychopathology, consistent with the Research Domain Criteria initiative. Cross-sectional research using categorical diagnoses indicates that P300 is an electrocortical endophenotype indexing genetic vulnerability to externalizing problems. However, current diagnostic systems' limitations impede a precise understanding of risk. The Hierarchical Taxonomy of Psychopathology (HiTOP) overcomes these limitations by delineating reliable dimensions ranging in specificity from broad spectra to narrow syndromes. The current study used a HiTOP-aligned approach to clarify P300's associations with a higher-order externalizing factor versus syndrome-specific manifestations within externalizing and internalizing spectra during middle and late adolescence. Participants from the Minnesota Twin Family Study's Enrichment Sample contributed psychophysiological and clinical data at age 14 (N = 930) and follow-up clinical data at age 17 (N = 913). Blunted target P300 at age 14 was selectively associated with externalizing as manifested at age 17 at the superspectrum level (rather than specific externalizing syndromes). Unlike in prior work, target P300 amplitude was positively associated with age 17 depressive symptoms (once controlling for standard stimuli). No association was observed with lifetime symptoms of childhood externalizing or depression evident by age 14. The results indicate that blunted target P300 elucidates specific risk for the development of late-adolescent/young-adult expressions of general externalizing, over and above symptoms evident by middle adolescence. Additionally, the findings speak to the synergistic utility of studying HiTOP-aligned dimensions using multiple measurement modalities to build a more comprehensive understanding of the development of psychopathology. (PsycInfo Database Record (c) 2024 APA, all rights reserved).