DOES IMMEDIATE AROUSAL ENHANCE RESPONSE FORCE IN SIMPLE REACTION-TIME

Three experiments assessed the hypothesis that immediate arousal enhan ces response force in speeded reaction-time tasks, Immediate arousal w as manipulated via the physical characteristics of a warning signal th at closely preceded the imperative response signal. The first experime nt revealed that responses were more forceful and faster for a loud th an for a soft warning signal, The second experiment manipulated the du ration of an auditory warning signal; more forceful but slower respons es were obtained for longer durations of the warning signal. The third experiment employed a visual warning signal, and its intensity was ei ther rather weak or moderately bright; more forceful responses and sli ghtly faster responses were observed for the brighter warning signal, Although the results of Experiment 1 and 2 may agree with an arousal a ccount, the findings of Experiment 3 argue against such an account. A stimulus-response compatibility hypothesis is suggested as one possibl e alternative account.