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Expectation, Excitation, Subjectivity, Idiosyncrasy, Placebo, and the Psychedelic Micro-dosing Experiment

APAStatementPsychedelics22A systematic study of microdosing psychedelics: Taken together these findings paint an intriguing picture. We found clear changes in a small set of psychological variables: decreased depression and stress; decreased mind wandering; increased absorption; and increased neuroticism. Notably, these variables were not those that participants most expected to change. If the current findings were entirely due to expectation, then we should have seen changes in those variables that are most commonly discussed in media and online accounts of microdosing, and in those variables rated highest in Study Two. In fact several of the most commonly discussed effects of microdosing and the effects most expected to change (creativity, wellbeing, mindfulness) showed no evidence of alteration whatsoever. This suggests that the longer term changes we identified were unlikely to be due to expectation.

On the other hand, although we did identify clear short term changes following each microdose in the daily analyses, the longer term changes identified in Study One were unrelated to the total number of doses participants ingested during the study period and also unrelated to participants’ prior microdosing experiences. This surprising lack of a relationship between the overall quantity of microdoses and the degree of subjective effects is a reason to interpret these findings cautiously. At face value this suggests that any engagement with microdosing, whether a single dose or relatively frequent dosing, can impact the variables we identified. This may be the case, but it is also possible that participants’ self reports of dosage and frequency in this study were not precise enough to accurately characterise dose related effects.

Overall, these findings suggest several disconnects between the popular narrative around microdosing and the experience of microdosers in this sample. Participants in Study One microdosed less often than is recommended in most online protocols and did not report that many of the immediate effects of microdosing lasted beyond the day of dosing. Although popular accounts of microdosing describe sustained boosts in productivity and creativity [16–18], the longer term effects we identified mainly involved reduced mental distress and changes in constructs such as absorption and mind wandering that are not as commonly discussed. This suggests that microdosing may lead to more subtle changes characterised by improvements in mental stability, the capacity to sustain attention and increased ability to become engaged in intense imaginative experiences.

The most surprising finding was that neuroticism also appeared to increase following microdosing. This is not something that is discussed in popular accounts of microdosing and was not what participants expected in Study Two. This highlights an important and under discussed aspect of microdosing: not everyone has a positive experience. Although the majority of participants’ comments were positive (and even glowing), there were a subset of comments that reflected unease about microdosing (see Table 5). In a context of considerable hype around the practice of microdosing, particularly with regards to it’s potential as a business tool, it important to acknowledge that microdosing may not be universally beneficial. These findings highlight the need for further research into the full range of microdosing effects (positive and negative) and also for investigations into subtypes of individuals who may particularly benefit from or be adverse to the practice.

Strengths, limitations and future directions

This was very much a preliminary and exploratory study of microdosing, and there are clear limitations to the study design. This was a self reported observational study and as such, we relied on participants’ accuracy and honesty in their reports of doses and effects, and also on their continued responsiveness throughout the study period. Recruitment for this study occurred through online forums that were mainly very positive about the effects of microdosing. As such, these results may be affected by sampling bias, and may under represent individuals with negative or ambivalent experiences of microdosing. Furthermore, as might be expected in an observational study of individuals who are interested in psychedelics, there was some concurrent use of higher dose psychoactive substances and non psychedelic substances that may have had some influence on these results. A better design would certainly be to conduct an experimental study with controlled doses of known substances and a placebo comparison condition. The legal and bureaucratic limitations around psychedelic research make the approval process for such a study prohibitive. As an alternative, in implementing the current design we aimed to demonstrate that it is possible to investigate the effects of psychedelic substances in a systematic observational paradigm, using an automated and anonymous communication system.

It is clear from this research that there is a high level of popular interest in microdosing, that many people are engaged in this practice, and that there are strong expectations about the various effects that microdosing can have. The current findings suggest that popular accounts of the effects of microdosing may not match the experience of long term microdosers, and that promising avenues for future investigation are the impacts of microdosing on improved mental health, attentional capabilities, and neuroticism.

For complete study

Further Reading

Psychedelics: The New Panacea – Just Like Cannabis, it will Fix Everything, Won’t it? 


Download Papers

Position Use of Psychedelic Empathogenic Agents APA 2022

A Systematic Study of Microdosing 2019



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