Visual Surround Suppression and Perceptual Expectation Under Psilocybin

The prospective study will address the critical need for more precise characterizations of the acute visual effects of the drug psilocybin by measuring the impact of acute psilocybin intoxication on a perceptual task known as visual surround suppression, compared to an active placebo control.

Trial Details



Trial Number

Sponsors & Collaborators

University of Minnesota
Researchers at the Nielsen Lab at the University of Minnesota are diving into the world of psychedelics and drug policy reform.

Minneapolis Veterans Affairs Medical Center
This company doesn't have a full profile yet, it is linked to a clinical trial.

Papers

Enhanced visual contrast suppression during peak psilocybin effects: Psychophysical results from a pilot randomized controlled trial
This placebo-controlled study (n=6) investigates how psilocybin (25mg) affects visual surround suppression compared to placebo (100mg niacin). The study finds increased surround suppression effects under psilocybin, with stronger suppression correlating with more intense subjective visual effects.

Measures Used

Mystical Experience Questionnaire
The MEQ is a self-report measure that has been used to measure mystical-type experiences in laboratory studies of psychedelics. The scale was developed by Walter Pahnke in 1963 and covers the major dimensions of classic mystical experience: unity (internal and external), transcendence of time and space, noetic quality, sacredness, positive mood, and ineffability/paradoxicality. Variations of the MEQ exist; the MEQ-30 and the MEQ-43.

5-Dimensional Altered States of Consciousness Questionnaire
The 5D-ASC scale measures altered states of consciousness and contains 94 items (visual analog scales).

Data attribution

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