Microdosing is the term for taking a sub-perceptual dose of a psychedelic drug. Anecdotal accounts of the mental health benefits are informing hypotheses on the possible psychological effects of microdosing.
Janet Lai Chang, a businesswoman, endurance athlete and psychedelics biohacker, will report on her year of psilocybin microdosing at the upcoming Quantified Self Conference in Amsterdam, June 17-18. She says, "I’ll share data from my 12+ month experiment with sub-perceptual doses of psilocybin for the purposes of increasing social skills through decreased anxiety and elevated mood, empathy, and verbal fluidity."
Above, a video from Chang's 2016 talk about her experiences with microdosing.