Psychedelic substances have been used almost since the beginning of recorded history to alter consciousness and produce spiritually meaningful experiences. Psychedelics produce effects that are similar to those that are reported in spiritual awakenings. They report a loss of the personal self. They experience what they used to refer to as the self as just a part of an integrated whole. They report feeling interconnected with everything else in a sense of oneness with all things. They experience a feeling of timelessness where time seems to stop and everything is taking place in a single present moment. They experience ineffability, being unable to express in words what they are experiencing and as a result sometimes producing paradoxical statements. And they experience a positive mood, with renewed energy and enthusiasm.
It is easy to see why people find these experiences so pleasant and eye opening. They often report that the experiences changed them forever. Even though the effects of psychedelic substances have been experienced and reported on for centuries, only very recently have these effects come under rigorous scientific scrutiny. One deterrent to the research is the legal prohibitions for the possession and use of these substances. One way around this problem is to take advantage of natural groupings of individuals who regularly use psychedelic substances.
In today’s Research News article “Long-term use of psychedelic drugs is associated with differences in brain structure and personality in humans.”
Bouso and colleagues took advantage of the fact that a substantial number of Brazilian religious groups ingest the natural psychedelic substance ayahuasca on a regular basis for ritual purposes. These groups, like many users of psychedelic substances, employ them to develop spirituality and self-transcendence. The investigators used neuroimaging to investigate the differences in brain structure between long-term (at least 50 uses) users of ayahuasca and matched control participants.
Bouso and colleagues found that the ayahuasca users had a thinning of a number of midline structures of the brain especially the posterior cingulate cortex.in addition, the amount of this thinning was positively related to the length of time that the individual had been using ayahuasca. The thinning suggests that there is a eduction in the use and importance of the structures. Importantly, the ayahuasca users did not differ from controls in the incidence of psychological problems or neuropsychological function. This suggests that the use of ayahuasca does not produce psychological or cognitive harm.
One of the most interesting findings was a significant increase in self-transcendence in the ayahuasca users. This included and increase in self-forgetfulness, which represents a decrease in self-conscious experience, transpersonal identification, which is seeing oneself as not isolated but merely a part of an integrated whole, and spiritual acceptance, which is an increase in viewing life as beyond the physical. Hence this self-transcendence is an indicator of increased spirituality and loss of the personal ego.
It is interesting that the midline structures including posterior cingulate cortex that are thinned with ayahuasca use are considered key elements of what’s termed the default mode network. This is an interconnected set of neural structures that becomes most active when the individual is lost in thought, day dreaming, and involved in self-referential thinking. In other words this system becomes active when the individual has lost touch with the present moment and his/her thoughts are referenced to a separate self.
So, the anatomical findings correlate nicely with the psychological findings for the ayahuasca users and suggest that the use of this psychedelic appears to be psychologically relatively harmless and appear to accentuate experiences that are virtually identical to those occurring in spiritual awakenings. This may suggest that spiritual awakening and psychedelic substance effects work through the same neural mechanisms.
“Through all of history mankind has ingested psychedelic substances. Those substances exist to put you in touch with spirits beyond yourself, with the creator, with the creative impulse of the planet.” – Ray Manzarek
CMCS – Center for Mindfulness and Contemplative Studies