Psychedelics and dreaming

Lots of people have commented on the similarities between dreaming and the psychedelic experience. We may be closer to a neurological explanation, according to this article by Robin Carhart-Harris and David Nutt of Imperial College, London. (Via the Psychedelic Frontier community on Goggle Plus.)

French researchers produced “transient dreamlike states” by electrical stimulation of the posterior cingulate cortex (PCC), a central part of the brain’s default mode network (DMN). Carhart-Harris and Nutt compared these results with their own studies of the brain during the psychedelic experience.

They report that changes in the PCC were “the most conspicuous and reliable finding of our psilocybin imaging studies.” They also note the role of the PCC in rapid eye movement (REM) sleep, the phase of sleep associated with dreams. Psilocybin and other psychedelics bring on rapid eye movement during sleep.

Another similarity suggests that psychedelics may have long-term therapeutic benefits. The patient in the French study reported a sustained period of “absolute happiness” after the experiment. Likewise, some subjects in psychedelic studies report a long-lasting sense of well-being after a few sessions.

Carhart-Harris and Nutt speculate that “psilocybin produces a sustained alteration in PCC and/or DMN activity that could account for its putative therapeutic potential.” They intend to follow up by testing the use of psilocybin for treating major depression.