Major Depressive Disorder (MDD)Bipolar DisorderDepressive DisordersHealthy VolunteersBorderline Personality Disorder (BPD)Personality DisordersInterpersonal Functioning & Social ConnectednessPsilocybin

Effect of psilocybin on empathy and moral decision-making

This placebo-controlled study (n=56) investigated the acute effect of psilocybin (15mg/70kg) on empathy and moral decision-making in healthy human subjects. The results found the first such evidence that psilocybin has distinct effects on social cognition by enhancing emotional empathy but not moral behavior. It also supports previous findings, indicating that psilocybin may promote emotional empathy presumably through activation of serotonin 2A/1A receptors, showing that focusing on serotonin 2A/1A receptors has the potential to treat dysfunctional social cognition.

Authors

  • Franz Vollenweider
  • Katrin Preller
  • Matthias Kometer

Published

International Journal of Neuropsychopharmacology
individual Study

Abstract

Background

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 behavior. Although the serotonin system has been implicated in modulating empathy and moral behavior, the relative contribution of the various serotonin receptor subtypes is still unknown.

Methods

We investigated the acute effect of psilocybin (0.215 mg/kg p.o.) in healthy human subjects on different facets of empathy and hypothetical moral decision-making using the multifaceted empathy test (n=32) and the moral dilemma task (n=24).

Results

Psilocybin significantly increased emotional, but not cognitive empathy compared with 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.

Conclusions

These findings provide first evidence that psilocybin has distinct effects on social cognition by enhancing emotional empathy but not moral behavior. Furthermore, together with previous findings, psilocybin appears to promote emotional empathy presumably via activation of serotonin 2A/1A receptors, suggesting that targeting serotonin 2A/1A receptors has implications for potential treatment of dysfunctional social cognition.

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Research Summary of 'Effect of psilocybin on empathy and moral decision-making'

Introduction

Empathy and moral behaviour are central to social functioning and are implicated in several psychiatric disorders. Empathy is described as having at least two components: cognitive empathy (understanding another's mental state, akin to Theory of Mind) and emotional empathy (sharing another's emotional state). Deficits in these domains are reported in conditions such as major depressive disorder, bipolar disorder, borderline personality disorder and psychopathy, and may worsen with illness progression. Moral decision-making is commonly studied using hypothetical moral dilemmas that pit utilitarian outcomes against deontological constraints; personal dilemmas that involve directly harming another person are more emotionally engaging and tend to elicit deontological responses. Serotonin (5-HT) has been implicated in both empathy and moral processes, but the specific contributions of different 5-HT receptor subtypes remain unclear. Previous pharmacological work showed that MDMA increases emotional but not cognitive empathy, and that manipulating 5-HT tone with SSRIs can increase harm aversion in moral judgements, suggesting receptor-specific effects worth clarifying. Pokorny and colleagues set out to test the acute effects of psilocybin — a serotonergic hallucinogen acting primarily at 5-HT2A and also 5-HT1A receptors — on multiple facets of empathy and on hypothetical moral decision-making in healthy volunteers. The principal hypotheses were that psilocybin would impair cognitive empathy for negative stimuli while increasing emotional empathy, and that it would reduce utilitarian choices in personal moral dilemmas. The study therefore examined cognitive empathy, explicit and implicit emotional empathy using the Multifaceted Empathy Test (MET), and moral choice behaviour using a moral dilemma task (MDT), in a double-blind, placebo-controlled, within-subject design.

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Study Details

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