Caffeine improves anticipatory processes in task switching.
We studied the effects of moderate amounts of caffeine on task switching and task maintenance using mixed-task (AABB) blocks, in which participants alternated predictably between two tasks, and single-task (AAAA, BBBB) blocks. Switch costs refer to longer reaction times (RT) on task switch trials (e.g. AB) compared to task-repeat trials (e.g. BB); mixing costs refer to longer RTs in task-repeat trials compared to single-task trials. In a double-blind, within-subjects experiment, two caffeine doses (3 and 5mg/kg body weight) and a placebo were administered to 18 coffee drinkers. Both caffeine doses reduced switch costs compared to placebo. Event-related brain potentials revealed a negative deflection developing within the preparatory interval, which was larger for switch than for repeat trials. Caffeine increased this switch-related difference. These results suggest that coffee consumption improves task-switching performance by enhancing anticipatory processing such as task set updating, presumably through the neurochemical effects of caffeine on the dopamine system.
Tieges
Zoë
Z
Department of Psychology, University of Amsterdam, Roetersstraat 15, Amsterdam, The Netherlands. Z.Tieges@uva.nl
Snel
Jan
J
Kok
Albert
A
Wijnen
Jasper G
JG
Lorist
Monicque M
MM
Richard Ridderinkhof
K
K
D000293:Adolescent; D000328:Adult; D001288:Attention / Q000187:drug effects*; D001931:Brain Mapping; D002110:Caffeine / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects; D002755:Choice Behavior / Q000187:drug effects*; D003118:Color Perception / Q000187:drug effects*; D003265:Contingent Negative Variation; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004569:Electroencephalography / Q000187:drug effects; D018913:Event-Related Potentials, P300 / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D009949:Orientation / Q000187:drug effects; D010364:Pattern Recognition, Visual / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects*; D012193:Reversal Learning / Q000187:drug effects; D012660:Semantics; D012718:Set, Psychology
D002110:Caffeine