Wednesday, July 18, 2012

Psilocybin and personality


ResearchBlogging.orgSome recent research suggests interesting connections between the effects of the psychedelic drug psilocybin and personality traits. A review of studies on factors affecting response to psilocybin found that after dosage, the strongest predictor of alterations in consciousness was the personality trait of absorption (Studerus, Gamma, Kometer, & Vollenweider, 2012). Absorption is defined as a person’s tendency to have episodes of “total” attention where a person’s awareness is fully engaged in whatever has their interest. The degree to which people had “mystical” type experiences while on psilocybin was related to their individual proneness to absorption. Absorption is associated with the broader personality trait openness to experience, which relates to a person’s receptiveness to new ideas and experiences. 


What I found particularly interesting was that another study on psilocybin found that people who had never before taken the drug experienced an enduring increase in their level of openness to experience that was evident more than a year later (MacLean, Johnson, & Griffiths, 2011). In this study, people who experienced what the researchers described as a “complete mystical experience” developed increased openness to experience whereas those who did not have such an experience had no increase in this trait. Because absorption is closely related to openness to experience, this suggests that there may be a two-way relationship between openness and mystical experiences associated with psilocybin. That is, people who are more open to their inner experience seem more likely to have a mystical experience and those who have a mystical experience tend to become more open as a result. There is evidence that individual differences in absorption are associated with particular neurotransmitter receptors that are acted upon by psychedelic drugs such as psilocybin (Ott, Reuter, Hennig, & Vaitl, 2005), which might explain why absorption-prone people are more responsive to the drug’s effects. Since psilocybin can apparently cause increases in openness to experience in some people, it seems possible that the drug might permanently increase the sensitivity of these neuroreceptors resulting in associated personality change. This would need to be confirmed by research. 

Another intriguing research question concerns what effects increased openness to experience might have. Openness to experience is associated with creativity among other things, so it would be interesting to scientifically examine whether psilocybin use leads to long-term improvements in creativity or other aspects of behaviour associated with openness to experience. In the 1960s many popular musicians experimented with psychedelic drugs such as LSD and this apparently influenced their music. Unfortunately, research into these drugs was effectively banned around this time and only recently has there been a revival of scientific activity in this area. Such research could lead to some intriguing findings about the relationship between the brain, personality, and consciousness.  

Addendum: Research psychologist Sanjay Srivastana presents a thoughtful critique of the MacLean et al. study here. He recommended that the study be replicated with a control group to allow stronger inferences about the causal influence of psilocybin on openness to experience.


Other posts about psychedelic drugs and/or spirituality

Follow me on Facebook, Google Plus, or Twitter.
© Scott McGreal. Please do not reproduce without permission. Brief excerpts may be quoted as long as a link to the original article is provided.  

MacLean, K. A., Johnson, M. W., & Griffiths, R. R. (2011). Mystical Experiences Occasioned by the Hallucinogen Psilocybin Lead to Increases in the Personality Domain of Openness Journal of Psychopharmacology, 25 (11), 1453-1461 DOI: 10.1177/0269881111420188
Ott, U., Reuter, M., Hennig, J., & Vaitl, D. (2005). Evidence for a common biological basis of the absorption trait, hallucinogen effects, and positive symptoms: Epistasis between 5-HT2a and COMT polymorphisms. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 137B(1), 29-32. doi: 10.1002/ajmg.b.30197
Studerus E, Gamma A, Kometer M, & Vollenweider FX (2012). Prediction of psilocybin response in healthy volunteers. PloS one, 7 (2) PMID: 22363492