Oxytocin normalises the implicit processing of fearful faces in psychopathy: a randomised crossover study using fMRI

Abstract Adults with antisocial personality disorder with (ASPD + P) and without (ASPD-P) psychopathy commit the majority of violent crimes. Empathic processing abnormalities are particularly prominent in psychopathy, but effective pharmacological interventions have yet to be identified. Oxytocin modulates neural responses to fearful expressions in healthy populations. The current study investigates its effects in violent antisocial men. In a placebo-controlled, randomised crossover design, 34 violent offenders (19 ASPD + P; 15 ASPD-P) and 24 healthy non-offenders received 40 IU intranasal oxytocin or placebo and then completed an fMRI morphed faces task examining the implicit processing of fearful facial expressions. Increasing intensity of fearful facial expressions failed to appropriately modulate activity in the right anterior insula and bilateral midcingulate cortex in violent offenders with ASPD + P, compared to those with ASPD-P. Oxytocin abolished these group differences by enhancing fear-associated activity in key social brain areas in ASPD + P. This represents the first evidence of neurochemical modulation of the empathic processing of others’ distress in psychopathy. Main Text