Psychedelic Experiences Increase Mind Perception but do not Change Atheist-Believer Status: A Prospective Longitudinal Study

Introduction

Psilocybin and other classical psychedelics have longstanding associations with spiritual and religious practices, and recent empirical work has suggested they may sometimes shift beliefs or belief-like states. Prior studies have reported increases after psychedelic use in constructs such as mind perception (the attribution of experience or agency to various entities), non-naturalistic or metaphysical beliefs (for example, dualism or idealism), and self-reported religious identification (Atheist-Believer status). However, much of that evidence comes from cross-sectional or retrospective surveys that are vulnerable to selection and recall biases, and some controlled trials lacked effective blinding or did not focus directly on belief change as a primary outcome. Nayak and colleagues set out to examine belief-related changes prospectively in a large sample of people who planned naturalistic psilocybin experiences. The study aimed to measure changes over time in three domains: mind perception toward a range of living and non-living targets, several metaphysical belief items (materialism, dualism, idealism, determinism), and self-classified Atheist-Believer status. The investigators hypothesised increases in mind perception, shifts toward non-naturalistic metaphysical beliefs, and movement from “nonbeliever” toward “believer.” The prospective design and multiple follow-up timepoints were intended to reduce recall bias and better characterise the magnitude and persistence of any changes occurring after naturalistic psilocybin use.