Journal of Vision
March 19, 2010
O. Carter, John D. Pettigrew, Felix Hasler et al.
3 citations
Binocular rivalry, the fluctuation in visual awareness when different images are shown to each eye, is slowed by the hallucinogenic compound psilocybin, the active ingredient in magic mushrooms. In ten healthy human subjects, psilocybin reduced the rate of switching between percepts and increased the experience of mixed or transitional percepts. Pretreatment with ketanserin, a selective 5-HT2A receptor antagonist, blocked most of psilocybin's positive psychotic-like symptoms but did not affect the slowing of binocular rivalry switching or negative symptoms related to reduced arousal and vigilance. This suggests that the slowing of binocular rivalry by psilocybin is not mediated by 5-HT2A receptors but may instead involve 5-HT1A receptor activation reducing serotonin release from the brainstem raphe nuclei, linking rivalry switching rate to arousal and attention.
medRxiv
December 23, 2025
Chiranth Bhagavan, O. Carter, Glenn Nielsen et al.
1 citation
Movement tasks such as walking, reaching, and dexterity tests were feasible for healthy volunteers who took psilocybin doses up to 15 mg. At 20 mg, impairments appeared in tasks that combined movement with cognitive demands, such as the Box and Block Test and Digit Symbol Substitution Test. Nausea (62% of participants) and headache (54%) were the most common adverse events; no serious adverse events occurred. Participants and physiotherapists guessed the dose correctly only about half the time, indicating adequate blinding. These results suggest that psilocybin-assisted physical rehabilitation may be safe and feasible for future trials in people with movement disorders.
Psychopharmacology
June 17, 2026
Pierre Klintefors, Chiranth Bhagavan, Richard Kanaan et al.
Low to moderate doses of psilocybin (5–20 mg) do not meaningfully disrupt manual dexterity or hand coordination in healthy adults. In a blinded trial, participants showed a modest biphasic dose-response pattern at higher doses (10–20 mg): slight impairment during peak effects and slight improvement 4.5 hours after administration, but effect sizes were small compared to baseline variability. Kinematic analyses found no substantial changes in movement smoothness or velocity, and the latent coordination structure remained stable, though finger movements showed a subtle increase in complexity. These results support the feasibility of combining psilocybin with active motor rehabilitation.