Drug Effects on Mood and Behavior - Expectancy

About This Study

This study will examine the effects of a single low dose of the 5HT2A agonist LSD (Lysergic Acid Diethylamide) (13 µg) or placebo in individuals who are or are not explicitly told what drug they will receive. Although it is known that expectancies strongly influence subjective responses to most drugs, no studies have examined expectancies on response to a very low dose of LSD. This is especially important in the context of 'microdosing' of drugs. People who practice microdosing typically do so with strong expectations of positive effects, making it difficult to determine whether there is a pharmacological effect. To minimize expectancies in the laboratory, participants are usually not told exactly what drug they will receive (i.e., double-blind), but given a range of possibilities. In the present study, the study team will test half the subjects under single-blind conditions, where the participants (but not the research assistant) will know exactly what they are receiving. Other subjects will receive the usual instructions. Healthy volunteers will receive either a marginally detectable dose of LSD (13 micrograms) or placebo, under conditions where they i) know for sure what drug they are receiving or ii) where the identity of the drug is uncertain. Four groups of subjects (N=12 each) will attend single 4-hour laboratory session. The study team will examine subjective and behavioral responses to the drug in each of four conditions (Known-Drug; Known-Placebo; Uncertain-Drug; Uncertain-Placebo).

Conditions Studied

Interventions

• •LSD
• •Placebo

Eligibility

Inclusion Criteria:

* English Fluency
* High school education or higher
* BMI between 19-30 kg/m2

Exclusion Criteria:

* Individuals with a medical condition contraindicating study participation as determined by the study physician (e.g., liver disease, abnormal EKG, liver or cardiovascular disease)
* High blood pressure (\>140/90)
* Current suicidal ideation or suicide attempt in past 12 months
* Past year severe substance use disorder
* Personal or first-degree relative with history of psychosis
* Currently taking any psychiatric medication (for conventional antidepressants must be off for ≥ 2 weeks)
* Active panic disorder
* Severe obsessive-compulsive disorder
* Severe post-traumatic stress disorder
* Women who are pregnant or planning to become pregnant

Study Locations (1)