Drug Effects on Mood and Behavior - Expectancy

Expectancies are known to influence responses to psychoactive drugs. The study team and others have shown previously, using a balanced placebo design, that expectancies influence responses to alcohol, nicotine, caffeine, stimulant drugs, and cannabinoids. In these studies subjects are randomly assigned to one of four conditions: Expect the drug and get the drug; Expect the drug and get placebo; Expect placebo and get the drug; Expect placebo and get placebo. This allows researchers to separate pharmacological effects from expectancy effects. Recently there has been much discussion about the role of expectancies specifically in responses to psychedelic drugs. Expectancies are especially important in the use of very low doses, referred to as 'microdoses'. These doses are typically at or below the threshold of detectability, but users take them with strong prior beliefs that the drugs improve mood and cognition. The beneficial effects have been difficult to demonstrate under laboratory conditions, perhaps because in the laboratory the drugs are administered without the explicit expectation of benefits, and the administration of the drugs is to some extent blinded. The present study is designed to separate the pharmacological effects of a low dose of LSD from effects that are influenced by expectancies.