Commentary on: Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance by Griffiths et al.

Psychedelic drugs such as psilocybin, lysergic acid diethylamide (LSD), mescaline, dimethyltryptamine (DMT), and many others include synthetic chemicals and the active ingredients in psychoactive extracts of plants that have been used since time immemorial for their mind-altering properties. These agents were first employed for religious purposes, evidently to facilitate contact with the supernatural. After the discovery of LSD by Albert Hofmann in the early 1940’s, much attention was devoted to the perceptual distortions elicited by LSD and related substances, as well as to the similarity of the drug-induced state to transcendental states reported by mystics of varied religious persuasions. The different effects elicited by these drugs have led to different names. They are designated “psychotomimetics” because one can reasonably argue that individuals taking the drugs have lost contact with reality and are, hence, psychotic. They are called “hallucinogens” because of the perceptual distortions. However, frank hallucinations— seeing or hearing something that doesn’t exist at all in the environment—are rare. Rather, visual and auditory perceptions are notably intensified and altered. Subjects report synesthesia, a seeming transmutation of the senses, e.g., visualizing sound waves upon hearing a loud noise. Humphrey Osmond coined the term “psychedelic” meaning “mind-manifesting” to emphasize the extraordinary change in the sense of self, a feeling of communion with the infinite, a dissolution of ego boundaries with the self, seeming to merge with environment. These are arguably the most remarkable of all the drug effects and may teach us much about neurochemical systems that mediate our sense of consciousness. Hence, I prefer the term psychedelic despite this term’s possibly connoting the irresponsible use of these drugs by some in the late 1960s. In the interests of full disclosure, I myself had single sessions each with LSD and DMT well over 40 years ago and experienced the effects described here. Numerous clinical studies with psychedelic drugs were conducted in the 1950s and 1960s. One of the few controlled investigations of the relationship of psychedelic drugs and mystical consciousness was carried out by Walter Pahnke as his doctoral dissertation at Harvard University. He utilized psilocybin, the psychoactive ingredient in the mushroom psilocybe, which for logistic reasons, has been the most widely employed psychedelic drug in clinical research. Psychedelic drugs vary in chemical structure with mescaline, (DOM), and 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy), being phenethylamines that resemble neurotransmitters such as norepinephrine and dopamine. Others, such as psilocybin, LSD, and DMT, contain indole moieties and more closely resemble serotonin. Extensive pharmacologic studies have established that all the drugs, phenethylamines and indoles, exert their actions primarily by mimicking serotonin at one of its receptor subtypes, 5-HT2A,C. In the Pahnke “Good Friday” study, groups of ten theological seminary students were administered either 30 mg psilocybin or 200 mg nicotinic acid in a group setting as part of a Psychopharmacology DOI 10.1007/s00213-006-0459-3