How psychedelic researchers’ self-admitted substance use and their association with psychedelic culture affect people’s perceptions of their scientific integrity and the quality of their research

Overall design and data handling. The research consists of three between-subjects experimental studies using vignette and mock-material manipulations. All participants were US-based MTurk workers with an approval rate of at least 95%. The authors implemented attention checks, prevented repeated participation across studies, and analysed data using IBM SPSS 23.0 with the PROCESS macro for moderation tests. Scales were aggregated into mean scores and negative items reverse-coded; internal consistencies (Cronbach's alpha) are reported for composite measures. Study 1. This between-subjects study randomly assigned participants to read a short vignette about a fictitious scientist (Prof. Miller) who researches psychedelics. The manipulation contrasted a version stating that the professor “has extensive personal experience with taking psychedelics” versus a version stating he “has no personal experience.” Participants (initial N = 201; final N = 185 after attention-check exclusions) rated the professor's scientific integrity (six adjectives: incompetent, professional, credible, impartial, biased, fraudulent) and the quality of his research (six adjectives: true, flawed, valid, important, meaningful, harmful) on 7-point Likert scales. Participants also reported their own history of psychedelic use (never, rarely, occasionally, often), later binary-coded for moderation analyses. Study 2. This conceptual replication (initial N = 471; final N = 414) increased sample size and elaborated materials. Participants saw a mock screenshot of a journal article about psilocybin and read a vignette varying whether the lead author had personal experience of taking psychedelics or not; the control vignette included parallel social behaviour (attending retreats but not ingesting) to hold constant related exposures. Measures were counterbalanced and included three composite DVs: researcher integrity (four items), research quality (four items), and the value/significance ascribed to the findings (four items about implementation, clinical potential, funding, and coverage). Attention checks and demographic questions (including participants’ own psychedelic experience) were also included. Study 3. The third study (initial N = 502; final N = 353) manipulated peripheral association with psychedelic culture rather than personal use. Participants viewed materials for a fictitious conference, “The Science of Psychedelics,” with the same scientific programme excerpt across conditions but differing in logo, colour scheme, venue image, and listed social events. The association condition used stereotypically psychedelic cues (black background, Peyote logo, colourful venue image, shamanic drum circle, group meditation, psychedelic art, communal floor seating), while the no-association condition used neutral conference cues (white background, geometric logo, ordinary auditorium, brewery tour, 5k run, postmodern art, typical table seating). None of the manipulations suggested illegal activity. Participants rated research quality (several items plus overall quality) and the perceived potential of psychedelics for clinical and non-clinical research. The authors tested main effects and moderation by participants' own psychedelic experience using regression analyses with interaction terms.

Study 1. After exclusions, 185 participants were analysed. Composite scores showed acceptable reliability for integrity (α = .76) and research quality (α = .92). Participants told that the researcher used psychedelics rated his scientific integrity lower (M = 4.96, SD = 1.10) than participants told he did not use them (M = 5.62, SD = 0.98), t(183) = 4.36, p < .001. Information about personal use did not significantly affect evaluations of research quality (substance use M = 5.26, SD = 1.25; no use M = 5.49, SD = 1.25), t(183) = 1.27, p = .204. Across conditions, participants with personal psychedelic experience evaluated both integrity and research quality more positively than those without experience. A binary moderator coding (experience vs no experience) did not significantly interact with the experimental manipulation for integrity (b = .21, SE = 0.35, p = .545). Study 2. The final sample was 414. Aggregated indices were internally consistent (integrity α = .84; quality α = .88; value α = .93). Replicating Study 1, participants read to be users of psychedelics rated the researcher's integrity lower (M = 4.26, SD = 1.30) than those read to be non-users (M = 5.09, SD = 1.32), t(412) = 6.38, p < .001, with a similar effect size to Study 1. No significant effect emerged on evaluations of research quality (users M = 5.02, SD = 1.25; non-users M = 4.83, SD = 1.39), t(412) = 1.42, p = .158, nor on the value/significance ascribed to the findings (users M = 4.63, SD = 1.59; non-users M = 4.77, SD = 1.57), t(412) = .89, p = .374. Participants with personal psychedelic experience (30.4% of the sample) rated integrity, quality, and value more positively overall, but personal experience did not moderate the effect of the manipulation on integrity (b = -.05, SE = 0.28, p = .871). Study 3. The final sample was 353. Aggregated research-quality scores showed high internal consistency (α = .95). Participants exposed to conference materials that associated the event with psychedelic culture evaluated research quality lower (M = 4.81, SD = 1.44) than those in the no-association condition (M = 5.31, SD = 1.09), t(332.97) = 3.62, p < .001, d = .40. Association did not affect participants' judgments about the overall value or potential of psychedelics in clinical/non-clinical domains (association M = 4.81, SD = 1.49; no association M = 4.95, SD = 1.26), t(345.09) = .95, p = .342. As in the prior studies, participants with personal psychedelic experience evaluated research quality and potential more positively overall. Importantly, moderation analysis revealed a significant interaction between experimental condition and participants' own psychedelic experience on perceived research quality (interaction b = .68, SE = 0.30, p = .023). Conditional effects showed that participants without personal psychedelic experience rated the research quality lower when the conference was associated with psychedelic culture (b = -.70, SE = 0.16, p < .001), whereas participants with personal experience showed no such attenuation (b = -.02, SE = 0.25, p = .942).

Forstmann and colleagues interpret their findings as evidence that peripheral, non-scientific attributes of researchers and research contexts influence public perceptions. Across three experiments (total N = 952), self-admitted personal psychedelic use consistently reduced perceived scientific integrity—participants judged such researchers as less professional, impartial, or more biased—even when the scientific content presented was identical. In contrast, declaring personal use did not reduce perceived research quality when findings were presented in a formal scientific context (Studies 1 and 2). By contrast, presenting research in a context that invoked psychedelic culture (Study 3) lowered perceived research quality, but only among participants without personal psychedelic experience; participants who had used psychedelics themselves were unaffected by the cultural cues. The authors situate these outcomes within frameworks of perceived trustworthiness, competence, and the halo/horn effect. They suggest several possible mechanisms: people may infer a hidden agenda, reduced moral character, or non‑prototypical scientist traits when researchers are seen as personally using psychedelics; similarly, stereotypical conference cues may lead lay observers to generalise negative views of a subculture to the competence or professionalism of its researchers. The investigators acknowledge that the exact psychological processes remain speculative and call for further work to unpack causality and mediators—particularly the roles of perceived motives, hypocrisy, and prior attitudes. Authors also note practical implications they believe follow from the data: peripheral cues, imagery, language, and public disclosures by scientists can materially affect public evaluation of scientific work. They propose that using less stereotypical imagery and being cautious about publicising personal substance use may help protect perceptions of integrity and research quality in sensitive domains, while recognising that continued, respectable association with psychedelic research might over time reduce stereotypes. The discussion closes by emphasising that because funding and administrative decisions are often made by people not associated with psychedelic culture, understanding factors that shape public and stakeholder perceptions is important for the field. The authors acknowledge limitations in specifying mechanism and recommend further research to clarify underlying processes and boundary conditions.

The authors conclude that how psychedelic researchers present themselves and how their work is contextualised affects lay perceptions: self-admitted personal use tends to reduce perceived scientific integrity, and peripheral association with psychedelic culture can reduce judged research quality among people without personal psychedelic experience. They advise caution in the use of stereotypical imagery and in public disclosures of personal substance use if the goal is to foster favourable public appraisal of research, while also noting that longer-term, respectable engagement between mainstream science and psychedelic-associated communities could, over time, change prevailing stereotypes. Understanding these perception dynamics is important given that public opinion and stakeholders influence funding and the administrative feasibility of conducting psychedelic research.