Psilocybin-induced spiritual experiences and insightfulness are associated with synchronization of neuronal oscillations

A moderate dose of psilocybin, a naturally occurring hallucinogen, decreased brain electrical activity at 1.5-20 Hz in a network involving the anterior and posterior cingulate cortices and parahippocampal regions. The intensity of spiritual experience and insightfulness correlated with the synchronization of delta oscillations (1.5-4 Hz) between the retrosplenial cortex, parahippocampus, and lateral orbitofrontal area. These findings directly link a specific spatiotemporal neuronal mechanism to spiritual experiences and enhanced insight into life, suggesting a pathway for modulating mental health and promoting well-being.

Study at a glance

Abstract

RationaleDuring the last years, considerable progress has been made toward understanding the neuronal basis of consciousness by using sophisticated behavioral tasks, brain-imaging techniques, and various psychoactive drugs. Nevertheless, the neuronal mechanisms underlying some of the most intriguing states of consciousness, including spiritual experiences, remain unknown.ObjectivesTo elucidate state of consciousness-related neuronal mechanisms, human subjects were given psilocybin, a naturally occurring serotonergic agonist and hallucinogen that has been used for centuries to induce spiritual experiences in religious and medical rituals.MethodsIn this double-blind, placebo-controlled study, 50 healthy human volunteers received a moderate dose of psilocybin, while high-density electroencephalogram (EEG) recordings were taken during eyes-open and eyes-closed resting states. The current source density and the lagged phase synchronization of neuronal oscillations across distributed brain regions were computed and correlated with psilocybin-induced altered states of consciousness.ResultsPsilocybin decreased the current source density of neuronal oscillations at 1.5-20 Hz within a neural network comprising the anterior and posterior cingulate cortices and the parahippocampal regions. Most intriguingly, the intensity levels of psilocybin-induced spiritual experience and insightfulness correlated with the lagged phase synchronization of delta oscillations (1.5-4 Hz) between the retrosplenial cortex, the parahippocampus, and the lateral orbitofrontal area.ConclusionsThese results provide systematic evidence for the direct association of a specific spatiotemporal neuronal mechanism with spiritual experiences and enhanced insight into life and existence. The identified mechanism may constitute a pathway for modulating mental health, as spiritual experiences can promote sustained well-being and psychological resilience.