Sequential effects in auditory choice reaction time tasks

This paper concerns sequential effects in choice reaction time tasks. Perfo rmance in two interleaved auditory tasks was examined, and two general type s of sequential effects were revealed. First, a response repetition effect occurred: Subjects were facilitated in responding when both the stimulus an d the response were immediately repeated. Generally, it appeared that subje cts were operating according to the bypass rule-that is, repeat the respons e if the stimulus or some aspect thereof is repeated from the preceding tri al; otherwise, change the response. Ln addition, the experiment also reveal ed a second type of sequential effect, known as a task-switching effect. Su bjects were overall slower to respond when the task changed between adjacen t trials than when there was no task change. A final result was that subjec ts were markedly impaired when the stimulus changed but the same response h ad to be repeated. This finding has been reported elsewhere when purely vis ual tasks have been used. Hence, it seems that particular difficulties aris e, in such sequential testing situations, when type-distinct stimuli are gr ouped into the same response categories.