The effects of caffeine on visual selective attention to color: an ERP study.
Event-related potentials were recorded from 11 subjects after ingesting caffeine (250 mg) or placebo. Subjects were instructed to attend selectively to stimuli with a specified color (red or blue) in order to react to the occurrence of a target within the attended category. Reaction times revealed faster responses for the caffeine condition, whereas no differences in strategy were observed. Color attention effects were identified as frontal selection positivity, occipital selection negativity, and N2b, whereas target detection was reflected in P3b. Effects of treatment were found as a more positive-going frontal P2 component in the caffeine condition. In addition, an interaction between attention and treatment could be observed on the N2b component. This pattern of results suggests that caffeine yields a higher overall arousal level, more profound processing of both attended and unattended information, and an acceleration of motor processes.
Department of Psychonomics, University of Amsterdam, The Netherlands.
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Ruijter
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De Ruiter
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Snel
D000328:Adult; D001288:Attention / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003118:Color Perception / Q000187:drug effects*; D018592:Cross-Over Studies; D004569:Electroencephalography / Q000187:drug effects; D004585:Electrooculography; D005071:Evoked Potentials / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male
D000697:Central Nervous System Stimulants; D002110:Caffeine