Narcissistic and Antisocial Personality Traits are both encoded in the Triple Network: Connectomics evidence

The neural bases of narcissistic and antisocial traits are still under debate. One intriguing question is whether these traits are encoded within the so-called triple network e.g. the default mode (DMN), salience (SN), and fronto-parietal (FPN) networks, and whether these traits affect the same networks in a similar manner. Connectome-based analyses were conducted on resting-state scans from 183 participants, examining regional and global graph-theoretic metrics in the DMN, SN, and FPN, with the visual and sensorimotor networks as controls. Our findings revealed a clear involvement of the triple network in narcissistic and antisocial traits, confirming a shared neural substrate for the two traits. Both traits were negatively predicted by the anterior cingulate cortex of the SN, possibly indicating less awareness of dangers and more proneness to engage in risky behaviors. Additionally, both traits were positively predicted by the lateral prefrontal cortex of the FPN, suggesting augmented strategic thinking to manipulate others and increased planning skills to achieve personal goals. Besides similarities, there were also some differences. Specific hubs of the DMN were positively associated with narcissism but negatively related with antisocials, possibly explaining their differences in self-reflection and thinking about the self, largely present in the former, but usually reduced in the latter. These results extend previous findings on the involvement of the triple network in personality disorders and suggest both common and different mechanisms underlying narcissistic and antisocial traits. As such, these findings could pave the way for developing potential biomarkers of personality pathology and identify neurostimulation intervention targets.