A meta-analytic evaluation of the N2 component as an endophenotype of response inhibition and externalizing psychopathology in childhood.

The N2 event-related potential component is a well-studied neurophysiological index of response inhibition that is considered to be a biomarker of externalizing psychopathology. The literature on the N2 elicited in childhood has been inconsistent, though, with different studies yielding different findings regarding the association between the N2 and the constructs it is thought to index. The current meta-analysis sought to clarify the functional meaning of the N2 component elicited in childhood across three widely used response inhibition tasks. The current study meta-analyzed the findings of 54 studies examining the association of the N2 component and three phenotypes of interest: (1) behavioral response inhibition (as indexed by performance on the inhibition trials of the task used to elicit the N2 component), (2) performance on behavioral measures of self-regulation, and (3) psychopathology (both externalizing and internalizing) in samples of children, to clarify the meaning of the N2 component and evaluate its utility as a potential endophenotype. Results suggest that the N2 component is associated with response inhibition and externalizing psychopathology.