Recreational use of psychedelics is associated with elevated personality trait openness: Exploration of associations with brain serotonin markers
This cross-sectional study found recreational psychedelic‑preferring users scored higher on openness to experience than MDMA‑preferring users and non‑users, with openness increasing with lifetime psychedelic exposures. Among users, frontal serotonin transporter — but not serotonin‑2A receptor — binding correlated positively with openness, linking serotonergic neurotransmission to personality differences.
Authors
- Gitte Knudsen
- Patrick Fisher
- Robin Carhart-Harris
Published
Abstract
Background
Recent studies have suggested therapeutic benefits of psychedelics for a variety of mental health conditions. The understanding of how single psychedelic administrations can induce long-lasting effects are, in large, still lacking. However, recent studies in both healthy and clinical populations suggest a role for personality changes.
Aim
To test support for some of these plausible mechanisms we evaluated (cross-sectional) associations between recreational use of psychedelics and 3,4-methylene-dioxymethamphetamine (MDMA) and (a) personality measures and (b) key markers of cerebral serotonergic signalling (serotonin transporter and serotonin-2A-receptor binding).
Methods
In 10 psychedelic-preferring recreational users, 14 MDMA-preferring users and 21 non-using controls, personality was assessed using the ‘big five‘ instrument Revised NEO Personality Inventory (NEO-PI-R). Frontal serotonin transporter and serotonin-2A-receptor binding potentials were quantified using [11C]DASB and [18F]altanserin positron emission tomography, respectively.
Results
Of the five NEO-PI-R traits, only openness to experience scores differed between the three groups; psychedelic-preferring recreational users showing higher openness to experience scores when compared with both MDMA-preferring users and controls. Openness to experience scores were positively associated with lifetime number of psychedelic exposures, and among all MDMA-preferring user/psychedelic-preferring recreational user individuals, frontal serotonin transporter binding – but not frontal serotonin-2A-receptor binding – was positively associated with openness to experience.
Conclusion
Our findings from this cross-sectional study support increasing evidence of a positive association between psychedelic experiences and openness to experience, and (a) expands this to the context of ‘recreational’ psychedelics use, and (b) links serotonergic neurotransmission to openness to experience. A modulation of personality induced by psychedelic experiences may have important therapeutic implications via its impact on peoples’ value systems, cognitive flexibility, and individual and social behaviour.
Research Summary of 'Recreational use of psychedelics is associated with elevated personality trait openness: Exploration of associations with brain serotonin markers'
Introduction
Psychedelic compounds such as psilocybin, mescaline and DMT produce acute perceptual changes and feelings of insight, connectedness and awe, and recent research has renewed interest in their therapeutic potential for conditions including addiction, anxiety and depression. MDMA, often classed as an 'empathogen' rather than a classic psychedelic, is also under investigation, notably for post-traumatic stress disorder. Both classes of drugs act primarily on the brain's serotonin (5-HT) system but by different mechanisms: MDMA increases synaptic serotonin via effects on the serotonin transporter (SERT), whereas classic psychedelics are 5-HT 2A receptor (5-HT2A-R) agonists. Clinical and experimental studies have reported that single or a few psychedelic/MDMA dosing sessions can produce effects that outlast the pharmacokinetic presence of the drug, including durable changes in personality, particularly increases in the Big Five trait openness to experience. Erritzoe and colleagues set out to investigate cross-sectional associations between recreational use of psychedelics or MDMA and (a) personality, measured with the Revised NEO Personality Inventory (NEO-PI-R), and (b) molecular markers of cortical serotonergic signalling measured by PET imaging of SERT and 5-HT2A-R binding. They hypothesised that openness would be higher among psychedelic and/or MDMA users than non-using controls, and that openness among users would correlate negatively with cortical 5-HT2A-R binding. The study therefore aims to link naturalistic exposure to serotonergic recreational drugs with both personality measures and neurochemical imaging markers to better characterise putative mechanisms underlying enduring effects of these compounds.
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Study Details
- Study Typeindividual
- Journal
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- Topics
- Authors
- APA Citation
Erritzoe, D., Smith, J., Fisher, P. M., Carhart-Harris, R., Frokjaer, V. G., & Knudsen, G. M. (2019). Recreational use of psychedelics is associated with elevated personality trait openness: Exploration of associations with brain serotonin markers. Journal of Psychopharmacology, 33(9), 1068-1075. https://doi.org/10.1177/0269881119827891
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