Communalistic use of psychoactive plants as a bridge between traditional healing practices and Western medicine: A new path for the Global Mental Health movement

The extracted text does not present a formal Methods section or report a systematic search strategy. Instead, the paper functions as a conceptual and theoretical synthesis. It draws upon the authors' previously published work, fieldwork experience, ethnographic examples, population and observational studies, preclinical findings, and recent clinical trials in the psychedelic literature. Ona and colleagues assemble illustrative case studies (for example, ayahuasca brigades, Bwiti iboga practices, and peyote ceremonies) and summarise mechanistic and epidemiological research to support their argument. No explicit inclusion/exclusion criteria, databases searched, or risk-of-bias assessments are reported in the extracted text, so the piece should be understood as a narrative review and position paper rather than a systematic review or meta-analysis.

The authors synthesise evidence and ethnographic description to advance three interrelated claims: communal rituals involving psychoactive plants promote social inclusion and cohesion; such practices can function as complex, culturally embedded health interventions; and biomedical investigation of psychoactive plants can help explain mechanisms while benefiting from traditional knowledge. On community and traditional medicine, the paper argues that community-level interventions often yield strong psychological benefits in LMICs by promoting connectedness, identity, meaning, empowerment, and social support. The authors link these benefits to classic sociological concepts such as Durkheim's "collective effervescence" and Turner's "communitas," and cite the WHO's calls for integrating traditional medicines into public health strategies. They also note that community-based and recovery-oriented approaches align with GMH aims. The paper offers concrete ethnographic examples. In Colombia, taitas (UMIYAC) have organised communal ayahuasca "health brigades" to address trauma in conflict-affected villages; the authors point to clinical literature reporting antidepressant and anxiolytic properties of ayahuasca and sustained mental-health and quality-of-life improvements among naïve users. In Gabon, iboga is embedded in Bwiti practices: routine small-dose soirees foster social bonding, while large-dose initiations play a ceremonial role. The authors summarise preclinical findings linking a single ibogaine administration to antidepressant-like effects in rodents and note ibogaine's historical and contemporary use in Western settings for opioid dependence. For peyote, the paper describes legally protected communal ceremonies among Indigenous groups in Mexico and the United States, ethnographic reports of people using peyote meetings for a range of health and social needs, and evidence suggesting complex interventions that include peyote ceremonies may help treat alcoholism. In these examples the authors emphasise non-pharmacological elements—shared meals, mutual care, and ritual symbolism—that contribute to health and resource distribution. Regarding biomedical bridging, the paper summarises mechanistic and epidemiological findings from the psychedelic literature. Neuroimaging studies are reported to show decreased connectivity within the default mode network (DMN) after psilocybin and ayahuasca administration; the DMN is briefly characterised as a brain network associated with self-referential processes and has been linked, when hyperconnected, with disorders such as depression and anxiety. Psilocybin is also reported to reduce segregation between brain regions and promote new long-range functional connections, which the authors describe as a reorganisation that may replace pathological circuits with more adaptive connectivity. Other proposed mechanisms include neuroendocrine, anti-inflammatory, and glutamatergic effects, as well as psychological processes such as personality change, meaning-enhancement, and the therapeutic role of the psychedelic/spiritual experience. The authors invoke the polypharmacology paradigm to argue that psychedelics act via multiple central nervous system targets rather than single-receptor mechanisms. Epidemiologically, the paper cites population studies indicating that psychedelic use is not a risk factor for later mental health problems, heightened distress, or suicidal behaviour. Observational comparisons of ritual practitioners and non-practitioners in traditional settings are reported to show mental-health and neuropsychological improvements for users of peyote and ayahuasca. However, the authors acknowledge that much of the evidence underpinning therapeutic claims has been generated outside of the original traditional contexts, and they stress that ritual and ceremonial frameworks may be important both for enhancing benefits and reducing risks. Lastly, the authors note organisational facts about GMH: since its launch in 2008, 225 institutions and over 15,000 individuals have joined the movement, and the WHO developed mhGAP (2008) and the mhGAP-Intervention Guide (2010) to support task-shifting and scaling up of mental-health services.

Ona and colleagues interpret their synthesis as supporting a shift in GMH towards genuinely pluralistic, community-centred models that integrate traditional communal uses of psychoactive plants with biomedical knowledge. They argue for a two-way, decolonising process in which biomedical research investigates mechanisms and safety while learning from traditional practices about context, ritual, and social deployment of these substances. The authors propose practical steps such as scaling up communal plant use in communities with historical traditions, confronting inappropriate drug policies, protecting human rights, and preserving territory and the environment. The discussion emphasises methodological and political considerations: integrating traditional medicine is ultimately a political endeavour requiring policies that strengthen communities; methodological tools such as Knowledge Dialogues and participatory action research are recommended to ensure equal-status engagement among community members, researchers, and clinicians. The authors also highlight legal and normative complexities, noting paradoxes such as peyote's Schedule I status in some jurisdictions despite its sacral recognition by Indigenous peoples. They position traditional practices as rich, complex interventions that combine pharmacology with social, nutritional, symbolic, and ecological elements, and suggest these could inform modern psychedelic therapies—particularly by reintroducing a stronger social and communal focus into treatments developed in high-income countries. Key limitations and cautions acknowledged by the authors include the heterogeneity and contextual complexity of traditional practices, which makes it risky to offer broad, transposable recommendations; the predominance of clinical and mechanistic evidence collected in non-traditional settings; and ongoing debates about psychiatric nosology and the biomedical model's limits. The authors call for further empirical work, careful legal and cultural analysis, and participatory approaches to co-develop context-appropriate integrations of traditional and biomedical care.

The authors conclude that the GMH movement is increasingly recognising the importance of local worldviews and practices for addressing mental health. They call on health authorities to adopt a new mentality that respects and leverages traditional communal uses of psychoactive plants, arguing these practices can offer community-level interventions that restore social connection while complementing biomedical treatments. The paper closes by noting that psychoactive plants have demonstrated therapeutic potential in Western research and that combining knowledge from traditional and biomedical systems could enrich mental-health care globally.