Behavioral effects of caffeine: The role of drug-related expectancies

This chapter reviews the concept of drug-related expectancy and describes studies that have examined the relationship between caffeine-related expectancies and behavioral responses to caffeine and to placebo. The research shows that expectancies about caffeine effects can influence behavioral responses to the drug. The findings also demonstrate the importance of using appropriate control groups for investigating the behavioral effect of caffeine and other psychoactive drugs. The chapter examines implications of this research for explaining individual differences in responses to caffeine, as well as for understanding factors that may contribute to the development and maintenance of caffeine consumption.