Biological psychiatry global open science
September 1, 2025
Čestmír Vejmola, Klára Šíchová, Kateřina Syrová et al.
4 citations
Psilocin, the active compound in psychedelic mushrooms, impairs the ability to distinguish between static and moving images in both humans and rats. In a visual discrimination task, human participants and male rats were asked to judge whether an image was static or moving. Under psilocin, both species showed significant difficulty in this task. In humans, the impairment tracked psilocin plasma levels and self-reported hallucination intensity. In rats, psilocin selectively disrupted performance in a motion-based task but not a luminance-based task, suggesting a specific effect on motion perception. Decision time was also linked to discrimination impairment. This is the first evidence that rats experience visual distortions similar to those reported by humans, offering a model for studying altered visual perception in drug-induced and psychiatric conditions.
Pharmacological reports : PR
June 16, 2025
Tereza Klučková, Marek Nikolič, Filip Tylš et al.
4 citations
In healthy individuals, psilocybin produces lasting positive effects regardless of previous psychedelic experience, repeated use, setting, sex, or occupation. In a double-blind, placebo-controlled crossover study with 40 participants (20 females, mean age 38), each received two doses of psilocybin (0.26 mg/kg) at least 56 days apart. Acute effects were moderate on the Altered States of Consciousness Scales, with mostly pleasant or fluctuating experiences and only one unpleasant session; all sessions ended positively or neutrally. Long-term effects, assessed by the Persisting Effects Questionnaire, were positive across all domains with negligible negative effects. Peak experiences ending in a positive mood strongly predicted favorable long-term outcomes, while challenging experiences did not cause adverse outcomes. These findings support psilocybin's psychological safety and repeated use in clinical trials.
The international journal of neuropsychopharmacology
August 1, 2025
Klára Šíchová, Barbara Mallarino, Lucie Janečková et al.
1 citation
Hexahydrocannabinol (HHC), a new psychoactive substance used as a legal alternative to ∆9-tetrahydrocannabinol, crosses the blood-brain barrier, exhibits mild toxicity, and induces behavioral effects similar to tetrahydrocannabinol in male Wistar rats. A 1:1 mixture of (9R)-HHC and (9S)-HHC was given at doses of 1, 5, and 10 mg/kg. Two hours after the highest dose, peak concentrations appeared in blood and brain tissue. The OECD 423 test classified HHC as Category 4, with an estimated lethal dose of 1000 mg/kg. Compared to controls, 10 mg/kg HHC reduced movement, increased anxiety, and impaired sensory processing, highlighting dose-dependent anxiogenic properties and impact on information processing.
Journal of psychopharmacology (Oxford, England)
May 28, 2025
Yana Vella, Kateřina Syrová, Aneta Petrušková et al.
1 citation
Psilocin, the active compound in magic mushrooms, promotes the formation of new synapses in rat brain cells, an effect comparable to ketamine and lithium. In laboratory experiments on rat cortical cultures, psilocin increased the number of synaptic puncta and boosted expression of the immediate early gene Arc after acute treatment. Lysergic acid diethylamide (LSD) and N,N-dimethyltryptamine (DMT) did not produce significant synaptogenic effects. Fluoxetine, a common antidepressant, had no effect on synapse formation but upregulated other immediate early genes. These findings add evidence that psilocin may be a promising therapeutic agent for psychiatric conditions.
bioRxiv Preprint Server
August 7, 2024
Yana Vella, Kateřina Syrová, Aneta Petrušková et al.
1 citation
preprint
Psychedelics can produce rapid and lasting antidepressant effects, likely through neuroplasticity, though the precise molecular mechanisms are not yet understood.