Psilocybin—Mediated Attenuation of Gamma Band Auditory Steady-State Responses (ASSR) Is Driven by the Intensity of Cognitive and Emotional Domains of Psychedelic Experience
Vojtěch Viktorin, Inga Griškova-bulanova, Aleksandras Voicikas, Dominika Dojčánová, Peter Zach, Anna Bravermanová, Veronika Andrashko, Filip Tylš, Jakub Korčák, Michaela Viktorinová, Vlastimil Koudelka, Kateřina Hájková, Martin Kuchař, Jiřı́ Horáček, Martin Brunovský, Tomáš Páleníček
Journal of Personalized Medicine June 19, 2022 DOI: 10.3390/jpm12061004 via OpenAlex
Summary
AI-generated from the abstractPsilocybin, a psychedelic compound, reduces the brain's ability to synchronize its electrical activity at 40 Hz in response to auditory clicks. In a double-blind, placebo-controlled crossover study, 20 healthy volunteers received either psilocybin (0.26 mg/kg) or placebo. Measurements taken before and after ingestion showed that psilocybin decreased the phase-locking index and amplitude of the 40 Hz auditory steady-state response, and the degree of this reduction correlated with changes in cognition and affect. These findings support the role of gamma oscillations in cognitive processing and their disruption in psychosis.
Study at a glance
| Characteristics | Randomized controlled trial Placebo-controlled Double-blind Peer reviewed |
|---|---|
| Sample size | 20 |
| Population | Healthy volunteers |
| Intervention | Psilocybin |
| Dose | 0.26 mg/kg |
| Topics | LSD Psilocybin |
| Keywords | Audiology Hallucinogen Crossover study Placebo |
| Citations | 19 |
| Key finding | Psilocybin decreases 40 Hz auditory steady-state response phase-locking index and amplitude, with the attenuation related to cognition and affect on the Hallucinogen Rating Scale. |
Abstract
Psilocybin is a classical serotoninergic psychedelic that induces cognitive disruptions similar to psychosis. Gamma activity is affected in psychosis and is tightly related to cognitive processing. The 40 Hz auditory steady-state responses (ASSR) are frequently used as indicators to test the ability to generate gamma activity. Based on previous literature, we studied the impact of psilocybin on 40 Hz ASSR in healthy volunteers. The study was double blind and placebo controlled with a crossover design. A sample of 20 healthy subjects (10M/10F) received psilocybin orally 0.26 mg/kg or placebo. Participants were measured four times in total, one time before ingestion of psilocybin/placebo and one time after ingestion, during the peak of intoxication. A series of 500 ms click trains were used for stimulation. Psilocybin induced a psychedelic effect and decreased 40 Hz ASSR phase-locking index compared to placebo. The extent of the attenuation was related to Cognition and Affect on the Hallucinogen Rating Scale. The current study shows that psilocybin lowers the synchronization level and the amplitude of 40 Hz auditory steady-state responses, which yields further support for the role of gamma oscillations in cognitive processing and its disturbance.