Over the past 20 years, analysis into psychedelic and cannabinoid-based remedies for psychological well being issues has quickly expanded.
Classical psychedelics (LSD, psilocybin and DMT) are being investigated as remedies for despair and nervousness (Wickham, 2024) and cannabis-based medicines are being more and more explored for a variety of indications from insomnia to tic issues, and autism (De Bode, 2024).
Because the scientific neighborhood grapples with a quickly evolving proof base, contrasting approaches to regulatory approval and authorities coverage have already begun to form public entry. In 2023, Australia turned the primary nation to licence psilocybin as a remedy for despair inside psychiatric settings (Henriques, 2023), In the meantime within the UK, cannabis-based medicinal merchandise at the moment are be prescribed by specialist medical doctors, though use is basically confined inside the personal sector.
As these beforehand prohibited substances change into extra utilised, acquainted questions resurface: what are their long-term results on the mind and psychological well being?
A brand new research by Bouso et al (2026) sought to discover this by investigating if long-term customers of hashish and ayahuasca (a natural brew containing DMT) differed to non-users with respect to character, cognition and psychological well being.
Strategies
This was a cross-sectional research based mostly in Spain evaluating measures of character, cognition, and psychological well being between ayahuasca, hashish, and non-regular substance customers.
Ayahuasca customers have been members of the Spanish Santo Daime Church, a non secular group the place ayahuasca is consumed ceremonially, whereas hashish customers have been members of Catalan cannabis-activist teams.
Individuals attended a screening go to, then a research go to the place a battery of neuropsychological, character and psychological well being scales have been accomplished. To be included members wanted to be abstinent from ayahuasca for 10 days, and hashish for 30 days previous to the research go to, and have a detrimental urine drug check on the day.
To determine how character, cognition and psychological well being differed throughout the teams, researchers used multinomial linear regression (MLR). To forestall overloading the mannequin with predictors, solely variables that exhibited a near-significant (p<0.1) relationship with consumer group have been included.
Variables have been entered into the MLR in levels (stepwise method). At every stage non-significant predictors have been eliminated. Mannequin match was assessed utilizing the Akaike Info Criterion (AIC) metric. A decrease AIC signifies a greater mannequin match with fewer pointless predictors.
Outcomes
The ultimate pattern comprised 219 members: 69 ayahuasca customers, 56 hashish customers and 94 non-regular substance customers. Lifetime publicity indicated long-term use with ayahuasca customers reporting a imply use of almost 190 occasions and hashish customers over 33,000 occasions.
The ultimate mannequin had an adjusted R2 worth of 28% that means that the included predictors defined 28% of the variability in group membership.
Stage 1: sociodemographic, psychiatric historical past and IQ
Hashish customers have been youthful, extra prone to be male, have decrease academic attainment and better fluid intelligence than non-user controls. Ayahuasca customers have been extra prone to have a earlier despair or nervousness analysis than non-users. When these variables have been added into the MLR, solely age, intercourse and former despair analysis remained statistically important predictors of group membership. This preliminary mannequin defined 8% of variability in group membership.
Stage 2: neuropsychological assessments
There have been no statistically important variations throughout consumer teams on measures of government functioning, working reminiscence, selective consideration, cognitive flexibility or determination making. These measures have been subsequently not included within the ultimate mannequin.
Stage 3: psychological well being signs
Hashish customers demonstrated statistically considerably decrease obsessive-compulsive and psychoticism scores than non-users. Nonetheless, none of those associations remained important as soon as entered into the MLR and have been subsequently not retained, suggesting the presence of psychological well being signs was much less necessary for distinguishing teams.
Stage 4: schizotypal traits
Ayahuasca customers reported extra uncommon experiences than wholesome controls, whereas hashish customers demonstrated higher impulsive non-conformity and introvertive anhedonia. Inclusion of those variables elevated the proportion of variance in group membership defined to 14.1%.
Stage 5: temperament and character dimensions
Ayahuasca customers demonstrated statistically considerably increased self-transcendence, and decrease persistence and hurt avoidance to wholesome controls. Hashish customers, alternatively, demonstrated higher novelty in search of than wholesome controls. These variables remained important within the MLR and inclusion elevated the defined variance to roughly 28%. This means that variations in temperament and character dimensions accounted for essentially the most variation in group membership.
Conclusions
Bouso et al. (2026) in contrast long-term ayahuasca customers, hashish customers and non-users on measures of cognition, psychological well being and character. Whereas consumer teams had substantial lifetime substance use, no variations have been recognized in assessments of government functioning, working reminiscence, consideration or decision-making.
Persona measures that assessed temperament and character dimensions defined the biggest variation in group membership. Ayahuasca customers demonstrated increased self-transcendence and decrease persistence and harm-avoidance to non-users, whereas hashish customers demonstrated higher novelty in search of.
Strengths and limitations
Finding out the long-term results of a drug is difficult. Customers typically eat a number of substances, differ in necessary sociodemographic traits, and should have co-morbid psychological well being circumstances. In an try and minimise the affect of those confounding variables, Bouso et al. (2026) adopted a novel naturalistic design, recruiting members from established social teams the place ayahuasca (Santo Daime church) or hashish (hashish activist networks) use was an built-in cultural apply.
Whereas this method strengthens the research by means of improved ecological validity by capturing functioning people with real-world publicity quite than skewed treatment-seeking populations, it doubtless launched choice bias. Spiritual organisations and activist networks could appeal to people with distinct beliefs, values and attitudes impartial of substance use. Consequently, though the noticed character profiles have been in keeping with earlier analysis (increased self-transcendence in ayahuasca customers and novelty in search of in hashish customers), it’s unclear whether or not these variations mirror neighborhood membership or the long-term results of the drug. With out potential evaluation, the path of causality can’t be inferred. The distinctive recruitment technique might also restrict the generalisability of the findings to individuals who use these substances outdoors these communities.
Whereas the distinct recruitment technique aimed to scale back the incidence of polysubstance use, members additionally reported utilizing different substances. This isn’t an uncommon discovering in drug analysis. Right here, greater than 40% of hashish customers reported MDMA or cocaine use within the earlier month and 42% of ayahuasca customers reporting hashish use within the final month. Though the frequency of use of those substances was not reported, these ranges of polysubstance use aren’t insignificant and should have contributed to the findings. Moreover, whereas the recruitment method was meant to enhance matching teams on age, intercourse, schooling and psychological well being historical past, variations between teams remained, with age, intercourse and former despair being retained within the ultimate mannequin.
Regardless of these limitations, the authors ought to be recommended for his or her efforts to minimise acute drug results by requiring each an abstinence interval and a detrimental drug check earlier than participation. That is notably necessary when investigating cognition, as earlier meta-analyses counsel that many cognitive deficits related to hashish use diminish following extended abstinence (Schreiner & Dunn, 2012). That mentioned, the 10-day abstinence interval for ayahuasca customers was meant to scale back acute results, nevertheless it stays unclear whether or not subacute modifications in neuroplasticity may nonetheless have influenced cognition or psychological well being outcomes (De Vos et al., 2021).
Moreover, the authors used a complete evaluation battery incorporating a number of validated assessments assessing quite a lot of cognitive domains, alongside questionnaires measuring psychopathology and character. This allowed the authors to check a number of competing explanations for group variations inside a single analytical framework.
Implications for apply
In 1987, anti-drug campaigners in the USA ran an commercial evaluating the results of medication on the mind to frying an egg.
Whereas Bouso et al.’s research challenges this simplistic message, discovering no important variations throughout a spread of neuropsychological assessments, the outcomes require cautious interpretation. Sure, ayahuasca and hashish customers on this research didn’t differ from controls on measures of working reminiscence, government functioning, selective consideration or cognitive flexibility. Nonetheless, this doesn’t essentially imply these substances don’t have any long-term cognitive results.
On the one hand, Bouso et al.’s cognitive findings align with earlier hashish analysis suggesting that cognitive deficits could diminish following extended abstinence (Schreiner & Dunn, 2012). Nonetheless, earlier critiques point out that cannabis-related cognitive outcomes could also be affected by age of onset, frequency of use, THC dose and co-occurring psychological well being difficulties (Kroon et al., 2021). As this was a cross-sectional research recruiting socially built-in customers, it’s attainable that people who skilled dangerous cognitive or psychological well being penalties arising from hashish have been much less prone to be recruited as a result of that they had already stopped utilizing hashish or have been not a part of these socially built-in communities. Subsequently, the research’s pattern could signify a subgroup of customers who can tolerate these substances or who had increased baseline cognitive functioning, maybe mirrored by the excessive fluid intelligence noticed amongst hashish customers.
Whereas the restrictions of the character findings have already been mentioned, the variations noticed between ayahuasca and hashish customers are notably attention-grabbing provided that particular person variations could affect one’s response to psychoactive substances. It is a central assumption in psychedelic analysis, the place “set” (a person’s mindset, expectations and character) and “setting” (the social, cultural and bodily surroundings through which a substance is taken) have been hypothesised to affect the acute drug experiences – though this has largely lacked empirical testing (Carhart-Harris et al., 2018). Subsequently, when character dimensions resembling self-transcendence are increased in ayahuasca customers this will not merely signify an impact of the drug or the kind of individual drawn to ayahuasca. As an alternative, it could mirror an interplay between character, the cultural context of use, and the drug’s pharmacological results. This interplay could have necessary medical implications as psychedelic- or cannabis-based remedies enter medical apply, with sure people probably being extra prone to search explicit substances and to expertise each desired therapeutic and antagonistic outcomes.
To disentangle these prospects, long-term potential analysis is required to find out if character traits predict subsequent substance use, and whether or not repeated publicity can itself produce lasting psychological modifications. Understanding who takes these substances, the context through which they’re consumed, and the way people make that means from these experiences could also be simply as necessary as understanding the pharmacological results of the substances themselves.
Assertion of pursuits
Matthew Cohen doesn’t know the researchers concerned on this research. He has been a research medic in psychedelic trials and has acquired cost for that work. AI was used to assist polish the textual content of this text to enhance readability.
Editor
Edited by Éimear Foley. ChatGPT assisted with language refinement and formatting through the editorial part.
Hyperlinks
Major paper
José Carlos Bouso, Jordi Riba et al (2026) Persona, not cognition, distinguishes continual ayahuasca and hashish customers from non-users. European Neuropsychopharmacology 106, 112782. https://doi.org/10.1016/j.euroneuro.2026.112782
Different references
Wickham R. Psychedelics and psychological well being: can the sector ship on its promise? The Psychological Elf, 2024.
Nationwide Elf Service weblog
De Bode N. Medical cannabinoids as a remedy for psychological well being: useful or hazardous? The Psychological Elf, 2024.
Nationwide Elf Service weblog
Henriques M. Australia turns into first nation to recognise psychedelics as medicines. BBC Information, 1 Jul 2023.
BBC Information article
Schreiner A.M, Dunn M.E. (2012) Residual results of hashish use on neurocognitive efficiency after extended abstinence: a meta-analysis. Experimental and Medical Psychopharmacology 20(5), 420–429. Full textual content
De Vos C.M, Mason N.L, Kuypers Okay.P.C. (2021) Psychedelics and neuroplasticity: a scientific evaluate unraveling the organic underpinnings of psychedelics. Frontiers in Psychiatry 12, 724606. Full textual content
Kroon E, Kuhns L, Cousijn J. (2021) The short-term and long-term results of hashish on cognition: current advances within the subject. Present Opinion in Psychology 38, 49–55. Full textual content
Lorenzetti V, Hoch E, Corridor W. (2020) Adolescent hashish use, cognition, mind well being and academic outcomes: a evaluate of the proof. European Neuropsychopharmacology 36, 169–180. Full textual content
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Carhart-Harris R.L, Roseman L, Haijen E. et al (2018) Psychedelics and the important significance of context. Journal of Psychopharmacology 32(7), 725–731. Full textual content
