Psychopaths and Sociopaths are wired differently
Background: Despite the relevance of narcissistic personality disorder (NPD) in clinical settings, there is currently no empirical data available regarding the neurobiological correlates of NPD. In the present study, we performed a voxel-based morphometric analysis to provide initial insight into local abnormalities of gray matter (GM) volume. Methods: Structural brain images were obtained from patients with NPD (n = 17) and a sample of healthy controls (n = 17) matched regarding age, gender, handedness, and intelligence. Groups were compared with regard to global brain tissue volumes and local abnormalities of GM volume. Regions-of-interest analyses were calculated for the anterior insula. Results: Relative to the control group, NPD patients had smaller GM volume in the left anterior insula. Independent of group, GM volume in the left anterior insula was positively related to self-reported emotional empathy. Complementary whole-brain analyses yielded smaller GM volume in fronto-paralimbic brain regions comprising the rostral and median cingulate cortex as well as dorsolateral and medial parts of the prefrontal cortex. Conclusion: Here we provide the first empirical evidence for structural abnormalities in fronto-paralimbic brain regions of patients with NPD. The results are discussed in the context of NPD patients’ restricted ability for emotional empathy.