Definition of Expectancy Effect

Smiling Man With Head In Cloud
Expectancy Effect.. PM Images / Getty Images

Definition: An expectancy effect is a psychoactive effect that happens in response to a person's expectation that a drug effect will occur. Expectancy effects include the placebo effect, and and can emphasize the perception of drug effects.

Pronunciation: ex-bek-tan-see

Examples: People experience an expectancy effect when they consume plain grapefruit juice, that they think contains alcohol, and feel intoxicated.

Continue Reading