Impaired empathic abilities lead to severe negative social consequences and influence the development and treatment of several psychiatric disorders. Furthermore, empathy has been shown to play a crucial role in moral and prosocial behaviour. Although the serotonin (5-HT) system has been implicated in modulating empathy and moral behaviour, the relative contribution of the various 5-HT receptor subtypes is still unknown.
We investigated the acute effect of psilocybin (0.215mg/kg p.o.) in healthy human subjects on different facets of empathy and hypothetical moral decision-making using the Multifaceted Empathy Test (MET) (n=32) and the Moral Dilemma Task (MDT) (n=24).
Psilocybin significantly increased emotional, but not cognitive empathy compared to placebo, and the increase in implicit emotional empathy was significantly associated with psilocybin-induced changed meaning of percepts. In contrast, moral decision-making remained unaffected by psilocybin.
These findings provide first evidence that psilocybin has distinct effects on social cognition by enhancing emotional empathy but not moral behaviour. Furthermore, together with previous findings psilocybin appears to promote emotional empathy presumably via activation of 5-HT2A/1A receptors suggesting that targeting 5-HT2A/1A receptors has implications for potential treatment of dysfunctional social cognition.
Pokorny, T., Preller, K. H., Kometer, M., Dziobek, I., & Vollenweider, F. X. (2017). Effect of psilocybin on empathy and moral decision-making. International Journal of Neuropsychopharmacology. 10.1093/ijnp/pyx047