Who Are You After Psychedelics? A Systematic Review and a Meta-Analysis of the Magnitude of Long-Term Effects of Serotonergic Psychedelics on Cognition/Creativity, Emotional Processing and Personality
Bayes, A., Brett, J., Haldane, K., Jayasena, T., Loo, C., Martin, D. M., Mason, N. L., Millard, M., Nikolin, S., Solaja, I., Weiss, B., Xu, M., Xu, X.
This systematic review & meta-analysis (2024; s=10; n=304) synthesized data from contemporary studies, including both randomised and non-randomised controlled trials, to evaluate lasting effects of serotonergic psychedelics on cognition, creativity, emotional processing, and personality. Overall, no statistically significant effects were observed for most outcome measures; however, a meta-analysis of emotional recognition outcomes revealed faster reaction times in the active treatment groups for disgust and sadness.
Abstract
This systematic review and a meta-analysis synthesised the results from contemporary, randomized and non-randomized controlled studies to assess lasting (one week minimum) changes on cognition/creativity, emotional processing and personality from serotonergic psychedelics. PubMed, Embase and PsycInfo were searched in July 2022. Risk of bias was assessed using Rob 2.0 and ROBINS-I. Ten studies met the eligibility criteria which involved 304 participants. No statistically significant effects were found for the majority outcome measures across the three constructs. A meta-analysis of emotional recognition outcomes found an overall significant effect for faster reaction times in the active treatment groups for disgust (SMD=-0.63, 95% CI=[-1.01 to -0.25], I2= 65%) and sadness (SMD=-0.45, 95% CI=[-0.85 to -0.06], I2= 60%). Future research should include larger samples, better control conditions, standardized doses and longer follow-up periods to confirm these preliminary findings.