Cortical Structure in Relation to Empathy and Psychopathy in 800 Incarcerated Men

Reduced empathy is a hallmark of individuals with high (i.e., clinical) levels of psychopathy, who are overrepresented among incarcerated men. However, a comprehensive, well-powered mapping of cortical structure in relation to empathy and psychopathy is still lacking.

In 804 incarcerated adult men, we administered the Perspective Taking (IRI-PT) and Empathic Concern (IRI-EC) subscales of the Interpersonal Reactivity Index (IRI), the Psychopathy Checklist-Revised (PCL-R; with interpersonal/affective [F1] and lifestyle/antisocial [F2] factors), and T1-weighted magnetic resonance imaging to quantify cortical thickness (CT), surface area (SA), and structural-covariance gradients.

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 the IRI subscales. In contrast, 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. Compared to men with low psychopathy, men with high psychopathy had uniquely lower IRI-EC scores and increased SA (but not CT); effect sizes across the cortex were largest in the paralimbic class and somatomotor network, while spatial overlap with meta-analytic task-based activations was highest for (social-)affective/sensory clusters. Finally, the total sample revealed anterior-posterior structural-covariance gradients; in men with high psychopathy, the gradient of CT (but not SA) was globally compressed.

Men with high psychopathy had reduced empathic concern, increased SA, and a compressed macroscale organization of CT, indicating selective co-alterations in empathy and cortical structure. Future work should build on these novel insights in both the general and incarcerated populations to inform the treatment of psychopathy.