Effects of psychedelic microdosing on cognitive functions: A systematic review and meta-analysis.
Netta Pinhas, Nofar Eidlman, Avigail Barnea, Leehe Peled-Avron
Neuroscience and Biobehavioral Reviews 2026 DOI: 10.1016/j.neubiorev.2025.106493 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Meta-analysis Preregistered Peer reviewed |
|---|---|
| Sample size | 1,614 |
| Population | Participants in studies of classical psychedelic microdosing |
| Duration | 1-42 days |
| Topics | LSD Microdosing Psilocybin |
| Keywords | Cognitive performance Meta-analysis Psychedelics |
| Citations | 2 |
| Key findings | Microdosing classical psychedelics significantly decreased cognitive control with no detectable effects on other cognitive domains. |
Abstract
Microdosing - the practice of consuming extremely low doses of classical psychedelic substances that do not elicit overt psychedelic effects - has gained significant attention as a potential method for enhancing cognitive performance. However, findings from controlled studies remain mixed and inconclusive. This preregistered meta-analysis examined the cognitive effects of classical psychedelic microdosing in 14 different studies (N = 1614), analyzing 59 effect sizes across multiple cognitive domains, spanning both acute (on-drug) and post-acute (off-drug) assessments. Results show a significant decrease in cognitive control, with no detectable effects on other cognitive domains or in general. Neither substance type (psilocybin or LSD), dosage (0.1-0.5 g psilocybin; 6.5-20 µg LSD), nor microdosing duration (1-42 days) emerged as significant moderators. Assessment timing (on- vs. off-drug) likewise did not moderate the effects. These findings suggest that microdosing may disrupt top-down cognitive control processes, aligning with cognitive and neural models of how classical psychedelics alter information processing in the brain to reduce rigidity and enable more fluid states of consciousness. However, better distinguishing between on-drug and off-drug effects is essential for clarifying whether microdosing exerts only transient pharmacological influences or promotes lasting cognitive change. Given the methodological heterogeneity across studies, future research using standardized protocols and mechanistic approaches is needed to fully characterize the cognitive and neural effects of microdosing classical psychedelics.
In the evidence
This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.
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Microdosing classical psychedelics significantly decreased cognitive control with no detectable effects on other cognitive domains, and neither substance type, dosage, nor duration moderated the effects.
Synthesized
Comparable studies
Other systematic reviews and meta-analyses on microdosing, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| The emerging science of microdosing: A systematic review of research on low dose psychedelics (1955–2021) and recommendations for the field Human participants in microdosing studies | 2022 | Systematic review | n = 44 |
| The utility of microdosing over the past 5 years Drugs with published comparisons of microdose and therapeutic dose pharmacokinetics | 2008 | Systematic review | n = 18 |
| The therapeutic potential of microdosing psychedelics in depression Healthy volunteers and patient samples | 2020 | Systematic review | |
| Potential safety, benefits, and influence of the placebo effect in microdosing psychedelic drugs: A systematic review | 2020 | Systematic review | |
| Microdosing Psychedelics: Current Evidence From Controlled Studies. Healthy adults | 2024 | Systematic review |