LSD-Perceptual-Choice-Study

NCT ID: NCT05976698

Last Updated: 2025-03-14

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 30 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-02-26
• Study Completion Date: 2025-02-25

Brief 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

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: DOUBLE

Study Groups

Intervention order: 10 μg LSD - 20 μg LSD - Placebo

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be 10 μg LSD - 20 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: active+active, 3. visit: placebo+placebo.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Intervention order: 10 μg LSD - Placebo - 20 μg LSD

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be 10 μg LSD - Placebo - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: placebo+placebo, 3. visit: active+active.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Intervention order: 20 μg LSD - 10 μg LSD - Placebo

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be 20 μg LSD - 10 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: active+placebo, 3. visit: placebo+placebo.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Intervention order: 20 μg LSD - placebo - 10 μg LSD

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be 20 μg LSD -placebo - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: placebo+placebo, 3. visit: active+placebo.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Intervention order: placebo - 10 μg LSD - 20 μg LSD

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be placebo - 10 μg LSD - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+placebo, 3. visit: active+active.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Intervention order: placebo - 20 μg LSD - 10 μg LSD

Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.

Order of drug administration will be placebo - 20 μg LSD - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+active, 3. visit: active+placebo.

Group Type: EXPERIMENTAL

LSD 10 μg

Intervention Type: DRUG

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).

LSD 20 μg

Intervention Type: DRUG

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.

Placebo

Intervention Type: DRUG

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.

Interventions

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).

Intervention Type: 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.

Intervention Type: 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.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• Willingness to adhere to the study protocol and sign the consent form
• ≥ 18 and ≤ 65 years of age at Screening
• Body mass index 18-29
• Fluent understanding of German
• Normal or corrected-to-normal vision
• Willingness to not operate a traffic vehicle or heavy machinery 24 hours after substance administration
• Willingness to refrain from taking illicit psychoactive substances, including cannabis, for the duration of the study
• Willingness to not consume more than one alcoholic standard drink the night before the study sessions and not consume alcohol for 24 h after each study session
• Willingness to abstain from xanthine-based liquids from the evenings prior to the study sessions and during the sessions
• Willingness to use effective birth-control throughout the study duration
• Adequate task performance in the decision-making tasks during a practice session in the screening visit

Exclusion Criteria

• Recent (<30 days) or current participation in another clinical trial
• Women that are pregnant, nursing, or planning to become pregnant during the study period
• Current use of contraindicated/psychoactive medications or illicit drugs
• Lifetime use of classical psychedelics more than 20 times, or any time within the previous two months
• Consumption of >5 cigarettes per day or >20 alcoholic standard drinks per week
• Severe chronic or acute medical condition
• Hypertension (>140/90 mmHg) or hypotension (<85mmHg systolic)
• Current or lifetime major mental health disorder
• Personal or family (first-degree) history of a primary psychotic disorder

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Basel

OTHER

Sponsor Role: collaborator

University Psychiatric Clinics Basel

NETWORK

Sponsor Role: collaborator

University Hospital, Basel, Switzerland

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Philipp Sterzer, Prof. Dr.

Role: PRINCIPAL_INVESTIGATOR

University Psychiatric Clinics Basel

Locations

University Psychiatric Clinics Basel

Basel, , Switzerland

Countries

Switzerland

Other Identifiers

2023-00763, pk23Sterzer

Identifier Type: -

Identifier Source: org_study_id