title: Caffeine expectancies but not caffeine reduce depletion-induced aggression.
abstract: Caffeine is the most widely consumed central nervous system stimulant in the world, yet little is known about its effects on aggressive behavior. Individuals often consume caffeine to increase energy and ward off mental depletion. Because mental depletion increases aggression when people are provoked, caffeine might reduce aggression by ameliorating the negative effects of depletion. In 2 experiments, participants consumed a 200-mg caffeine tablet or a placebo, were mentally depleted or not, and then provoked and given the opportunity to retaliate with a blast of white noise. Results showed that consuming a placebo reduced aggression relative to both caffeine (Experiments 1 and 2) and a no-pill control condition (Experiment 2). These data suggest that expectancies about the effects of caffeine in the absence of the pharmacological effects of the drug can reduce aggression when mentally depleted.
authors.affiliation: School of Psychology, University of New South Wales, Sydney, NSW, Australia. t.denson@unsw.edu.au
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Denson
authors.forename: Mandi
authors.initials: M
authors.lastname: Jacobson
authors.forename: William
authors.initials: W
authors.lastname: von Hippel
authors.forename: Richard I
authors.initials: RI
authors.lastname: Kemp
authors.forename: Tinnie
authors.initials: T
authors.lastname: Mak
mesh_terms: D000328:Adult; D000374:Aggression / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance / Q000187:drug effects
chemical_list: D000697:Central Nervous System Stimulants; D002110:Caffeine