Amplitude modulation of the Contingent Negative Variation in psychopathy: A systematic review and meta-analysis.

The CNV is analyzed in tasks related to EEG studies, often with participants presenting psychopathic personality traits. A systematic search of the literature was conducted, to solve some inconsistencies regarding CNV amplitude modulation by psychopathy. Nine studies (N = 317) were retrieved for analysis. Three meta-analyses were run - CNV, iCNV, tCNV. A qualitative analysis - reporting CNV amplitudes modulated by psychopathy dimensional features - was also featured. Overall effects for CNV and iCNV were not significant. Larger tCNV amplitudes were found in participants reporting higher psychopathy traits, g = -0.58, 95% CI [-0.94, -0.22]. These findings were surprising when confronted with previous assumptions in the literature, especially considering that no significant heterogeneity between studies was found. Neither of the studies' characteristics was a significant moderator. Findings require the need to discuss key differences between adaptive/(mal)adjustment patterns in participants presenting psychopathic traits. Future studies dissociating iCNV and tCNV modulation by psychopathy, especially in community samples and through a dimensional lens, could help to better understand the construct of psychopathy.