ERN as a transdiagnostic marker of the internalizing-externalizing spectrum: A dissociable meta-analytic effect.

The comorbidity between discrete clinical diagnosis occurs in higher levels than prevalence rates, indicating that mental disorders are systematically overcategorized. Dimensional models - as the Internalizing-Externalizing Spectrum - claim for a common latent structure of psychopathology. The current meta-analysis aims to evaluate whether the externalizing and internalizing latent factors of the psychopathological spectrum display common and distinctive neurobiological substrates, as unveiled by Error-Related Negativity (ERN) modulation. A systematic search of the literature was conducted and a total of 99 articles (160 studies, N = 8123) were included in the quantitative analysis. A dissociable effect was found: reduced ERN amplitude was observed in externalizing, while increased ERN amplitude was reported in internalizing. Larger effects were documented in all the externalizing dimensions (except for alcohol abuse) and were moderated by frontal electrode sites and tasks requiring inhibition. In internalizing, the overall effect was less robust. Disorder severity and tasks with punishment contingencies moderated the findings, and anxiety and obsessive-compulsive traits were the unique dimensions of internalizing accounting for the ERN increased amplitude. Overall, our findings highlight that ERN reduction interacts with the multiple phenotypic expressions of externalizing at a general level, while more specific factors - such as differences in sensitivity and aversion to errors - may explain increased ERN amplitude in internalizing.