Cortical structure in relation to empathy and psychopathy in 800 incarcerated men.

Background: Reduced empathy is a hallmark of individuals with high psychopathy, who are overrepresented among incarcerated men. However, a comprehensive mapping of cortical structure in relation to empathy and psychopathy is lacking. Methods: In 804 incarcerated adult men, we administered the Perspective Taking (IRI-PT) and Empathic Concern (IRI-EC) subscales of the Interpersonal Reactivity Index, Hare Psychopathy Checklist-Revised (PCL-R; Interpersonal/Affective [F1] and Lifestyle/Antisocial [F2] factors), and T1-weighted MRI to quantify cortical thickness (CT) and surface area (SA). We also included the male sample from the Human Connectome Project (HCP; N = 501) to probe the replicability of structural-covariance gradients. Results: PCL-R F1 was uniquely negatively related to IRI-EC, while PCL-R F2 was uniquely negatively related to IRI-PT. Cortical structure was not related to either IRI subscale, although there was effect-size differentiation by cytoarchitectonic class and/or functional network. CT was related to PCL-R F1 (mostly positively), SA was related to both PCL-R factors (only positively), and both cortical indices demonstrated out-of-sample predictive utility for PCL-R F1. The high-psychopathy group (N = 178) scored uniquely lower on IRI-EC while having increased SA (but not CT); across the cortex, effect sizes were largest in the paralimbic class and somatomotor network, and meta-analytic task-based activations corroborated affective/sensory importance. Finally, the total sample revealed anterior-posterior gradients of covariance, which were replicated in the HCP sample. In the high-psychopathy group, the gradient of CT (but not SA) was globally compressed. Conclusions: Most notably, high-psychopathy men had reduced empathic concern, increased SA, and compressed macroscale organization of CT.