NCT05976698

LSD-Perceptual-Choice-Study

Effects of LSD on Perceptual Decision-making in Healthy Subjects

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (actual)
• Sponsor: University Hospital, Basel, Switzerland · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

The aim of the study is to characterize the effects of low doses of LSD (d-lysergic acid diethylamide) on behavioral and neural indicators of feedback and feedforward signaling in perceptual decision-making.

Detailed description

The study team will subject healthy participants to multiple perceptual decision-making tasks after the administration of low doses of LSD (d-lysergic acid diethylamide) as a pharmacological challenge. The investigators want to illuminate the behavioral and neural effects of psychedelics on prior beliefs and evidence processing. Each subject will participate in 3 x 5 h study sessions separated by at least 7 days. Subjects will be under continuous supervision until approximately 4.5h after substance administration. The participants are asked to perform the following cognitive tasks alongside EEG measurement after administration of either LSD or placebo: Changepoint task, history bias task, surround suppression task, auditory steady-state response paradigm, motor localizer task.

Conditions

• LSD Reaction

Interventions

Type	Name	Description
DRUG	LSD 10 μg	0.5 h after the start of each study session the participants will be administered 10 μg LSD per os in the form of vials containing 1ml 20% EtOH (ethanol).
DRUG	LSD 20 μg	0.5 h after the start of each study session the participants will be administered 20 μg LSD per os in the form of vials containing 1ml 20% EtOH.
DRUG	Placebo	0.5 h after the start of each study session the participants will be administered placebo per os in the form of vials containing 1ml 20% EtOH.

Timeline

• Start date: 2024-02-26
• Primary completion: 2025-02-25
• Completion: 2025-02-25
• First posted: 2023-08-04
• Last updated: 2025-03-14

Locations

1 site across 1 country: Switzerland