Those who take magic mushrooms commonly report the experience of feeling one with the universe. Now scientists may be closer to understanding what happens in the brain during that mystical state.
Last month, researchers from Maastricht University in the Netherlands demonstrated the neurobiology at play when people on psilocybin experience a loss of their sense of self. Psychedelics are known to cause temporary loss of autobiographical information, dissolving the boundaries between one’s personal identity and the outside world. In the first-of-its-kind study, published in the journal Neuropsychopharmacology, findings suggest that the experience of ego loss is correlated with a neurotransmitter in the brain linked to self-awareness.
The research team focused their attention on glutamate, the brain’s most abundant neurotransmitter, believed to be related to self-awareness. In a double-blind, placebo-controlled trial of 60 healthy volunteers, they observed changes in the amount of glutamate after participants ingested a 0.17mg dose of psilocybin. The study observed changes in glutamate in two areas of the brain related to the self. One is the medial prefrontal cortex (mPFC)is known to be important in retrieving self-knowledge and in self-perception. The study also observed changes in the hippocampus, which is involved with self-esteem and autobiographical memory.
Participants recorded their experiences of ego dissolution by filling out two questionnaires, the Ego Dissolution Inventory (EDI), and the 5 Dimensions of Altered States of Consciousness (5D-ASC) scale, which asks subjects to rate statements such as, “I had the feeling everything around me was somehow unreal,” and, “I observed myself as though I were a stranger” on a scale of 1-10 depending on how well the statements matched their experiences. Researchers wrote that the dose given to study participants was considered low to moderate in comparison to previous psychedelic studies, and “not high enough to induce total ego dissolution,” or a complete loss of subjective self-identity.
The findings showed that the changes in glutamate “predicted distortions in the subjective experience of one’s self (ego dissolution),” wrote the authors in the study. The findings also provided insight on what areas of the brain were affected when subjects experienced either a perceived good or bad trip. A “positively experienced ego dissolution” was correlated with changes in glutamate levels in the hippocampus, while a negative experience was tied to changes in the mPFC.
While there exists observational evidence to back up these findings, this study marks the first time researchers have directly investigated how psilocybin impacts glutamate in the brain.