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Personality, not cognition, distinguishes chronic ayahuasca and cannabis users from non-users

José Carlos Bouso, Oscar Andión, Sabela Fondevila Estévez, Débora González, M. A. Alcázar-Córcoles, Maja Kohek, R. D. dos Santos, J. Hallak et al.

European Neuropsychopharmacology, 2026

94 participants

Abstract

The increasing interest in the therapeutic potential of psychedelics and cannabis underscores the need to understand their long-term neuropsychological and personality effects. This cross-sectional study compared regular users of ayahuasca (n = 69), cannabis (n = 56), and non-substance users (n = 94) on a battery of neuropsychological tasks and psychological questionnaires. Participants were matched by age, education, and IQ and abstained from drug use for at least 10-30 days before assessment. No significant group differences were observed in neuropsychological performance. However, multinomial regression analyses revealed that personality traits best distinguished the user groups. Ayahuasca users exhibited significantly higher self-transcendence and lower harm avoidance and persistence, while cannabis users were associated with higher novelty seeking and impulsive nonconformity, as well as lower introvertive anhedonia. These results persisted after controlling for demographics and psychiatric history. Contrary to previous findings associating cannabis with neurocognitive impairments and psychopathology, no significant deficits were found in the abstinent cannabis users. Similarly, ayahuasca users, despite a higher lifetime prevalence of mood and anxiety disorders, showed no current psychopathological symptoms. Our findings suggest that chronic use of ayahuasca or cannabis is not associated with detectable lasting neuropsychological impairments in the executive and working…

How strong is the evidence?

Evidence Hub reads this as a cross-sectional, done in people. Its evidence level is 4 of 5 (Low · observational). Observational designs can show an association but not prove cause. Reported size: 94 participants or records.

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