Effects of alcohol and caffeine on P300 and reaction time

Frances Martin, Joshua B.B. Garfield

Research output: Contribution to journalMeeting AbstractOtherpeer-review


The effects of alcohol and caffeine on the P300 component of the ERP and on the decision time and movement time components of reaction time were investigated to determine what stages of processing were affected by each drug,
and whether the effects of the two drugs interacted. Sixteen women aged 18-43 participated in a repeated measures experiment to test the effects of these drugs on P300 amplitude and latency, decision time, and movement time in both simple and choice reaction time tasks. Results revealed that alcohol lengthened both P300 latency and decision time equally. Alcohol also interacted with the effect of sagittal site on P300 amplitude suggesting specific effects on either memory capacity or subjective difficulty in the choice reaction time task. Caffeine shortened decision time in the choice RT task and increased P300 amplitude in the choice reaction time task. The results suggest that alcohol’s effects on speed of processing were expressed at an early stage of processing common to both elicitation of P300 and response, while those of caffeine were expressed in the stage of response decision. There is some indication that both
drugs may have affected participants’ subjective assessment of the choice reaction time task.
Original languageEnglish
Pages (from-to)23-23
Number of pages1
JournalAustralian Journal of Psychology
Issue numberS1
Publication statusPublished - Dec 2003
Externally publishedYes
Event12th Australasian Society for Psychophysiology Conference - University of Sydney, Sydney, Australia
Duration: 29 Nov 20023 Dec 2002

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