The Effects of Magic Mushrooms on the Brain

Psychopharmacologists Robin Carhart-Harris and David Nutt of Imperial College London have recently published the results of their study, which used fMRI technology to record the effects of psilocybin on the brain.

Although a few studies in the past have tried to measure the effects of hallucinogenic drugs on the brain, Carhart-Harris and Nutt are the first to use functional Magnetic Resonance Imaging (fMRI) to record brain activity while under the influence. Using psilocybin — an active ingredient in hallucinogenic mushrooms — the researchers recruited 30 people who had previous experience with hallucinogens. After delivering the drug intravenously, the researchers performed two types of fMRI scans on each person’s brain: the first, to measure blood flow throughout the brain, and the second, to determine blood oxygenation — normally an indicator of neural activity.

The scans indicated that psilocybin reduced blood flow as well as neural activity in a number of brain regions, creating a disconnect, particularly in the posterior cingulate cortex and medial prefrontal cortex. Both of these sections are part of the interconnected brain regions that are active when people are daydreaming. It has been suggested that these regions are important to introspective thought and the sense of conscious awareness. Nutt believes these findings “could help explain the surreal experiences the drug causes … This network in the brain that pulls together a sense of self becomes less active.”

Currently, Nutt plans to join forces with Roland Griffiths, a psychopharmacologist at Johns Hopkins University in Maryland, in order to explore the therapeutic potential of hallucinogenic drugs. They are particularly interested in the possibility of using psilocybin to relieve near-death cancer patients, treat depression, and enhance memory recall during psychotherapy.