The past decade has seen the thawing of a half-century moratorium on psychedelic research, allowing scientists to finally start investigating the effects of these intriguing compounds. Cutting-edge technologies have helped us make up for lost time, revealing how substances like LSD, psilocybin (magic mushrooms), and DMT affect brain activity and mental health. Several hypotheses have emerged from these experiments, some of which have become widely accepted, although a new study into the effects of a drug called salvinorin A has now cast doubt on everything we thought we knew about psychedelics.
Defining A Psychedelic
While any substance that alters our state of consciousness can claim to be a psychedelic, scientists tend to bestow the more exclusive title of "classic psychedelic" upon those drugs that interact with a serotonin (the "happy hormone") receptor called the 5-HT2A receptor. Magic mushrooms, LSD, and DMT all come under this category, although other mind-altering substances like salvinorin A do not. Commonly found in the plant Salvia divinorum, this compound produces an extremely intense trip that lasts for about 15 minutes, yet binds to a kappa opioid receptor rather than serotonin receptors.
According to a new study in the journal Scientific Reports, many of the neurological effects that are typically attributed to classic psychedelics are also observed when people take Salvia, indicating that we may need to revise our most popular theories regarding the impact of psychedelics on the brain.
Psychedelics And The Entropic Brain
Starting in about 2012, a wave of brain imaging studies revealed that classic psychedelics all precipitate a more “entropic” pattern of brain connectivity. This is characterized by an explosion of communication throughout the brain, as regions that wouldn’t normally have much to do with one another suddenly start interacting. Simultaneously, established connectivity patterns between certain brain regions break down, with the end result being a disintegration of brain networks.
Studies on psilocybin and LSD have tended to focus on the ramifications of this pheneomenon within the so-called default mode network (DMN), which controls everyday cognition and thought patterns. As the DMN disintegrates under the influence of classic psychedelics, people tend to experience ego-dissolution, whereby they lose the ability to locate themselves as a bound and distinct entity that is separate from the world around them.
However, the theory that DMN disintegration underpins the ability of classic psychedelics to shut down the ego took a knock when it was revealed that drugs like alcohol and cannabis also interact with the DMN, despite the fact that they don’t generate a sense of universal oneness. More significantly, it has now been revealed that Salvia dissolves the DMN in the same way as classic psychedelics, despite not being one.
It would therefore appear that reduced connectivity in the DMN is not unique to classic psychedelics, indicating that the ability of these substances to knock out a person’s sense of self may depend upon some other mechanism.