Microdosing psychedelics has no impact on cognitive function in naturalistic settings

Introduction

Earlier research and widespread anecdotal reports describe microdosing—regular ingestion of sub-perceptual amounts of classical psychedelics such as LSD or psilocybin—as an approach people use to boost cognition, mood and productivity. Experimental studies of medium and large doses have documented dose-dependent effects on attention, memory and executive functions, and some neurobiological mechanisms have been proposed (for example, effects on BDNF and functional connectivity). However, evidence for cognitive benefits from microdoses is sparse and mixed: some laboratory microdosing studies report small improvements in particular individuals, others find no change or slight impairments, and most prior work took place in tightly controlled experimental settings rather than in users' daily environments. This study, led by Dinkelacker and colleagues, set out to assess whether microdosing produces measurable changes in multiple neurocognitive domains when practised in naturalistic settings. The investigators aimed to provide a broad, within-subjects, longitudinal examination of processing speed, sustained attention, inhibitory control, cognitive flexibility, working memory, verbal memory and visual memory using remote testing and experience sampling over a 28-day period. By allowing participants to continue their habitual microdosing routines, the researchers sought to increase ecological validity relative to laboratory-based studies and to test whether acute (same-day or next-day) cognitive effects are detectable in everyday conditions.