Thomaschke, R. & Dreisbach, G.
Institut für Psychologie. Universität Regensburg. Regensburg, Germany.
We conducted two experiments to investigate whether temporal expectancy is specific to response effectors or response locations. In a speeded binary forced-choice task, participants used four different response buttons, two (up and down) left buttons and two (up and down) right buttons, operated by the index (down) and middle (up) finger of a given hand. Participants had to switch between the left and right button set from trial to trial. One stimulus was assigned to the upper (left/right) button, while the other was assigned to the lower button. In Experiment 1, both button sets were operated by different hands, so that fingers could rest on the buttons throughout the procedure, while in Experiment 2, participants had to operate both sets with one hand, so that fingers had to switch buttons from trial to trial. In both experiments, foreperiods (600 and 1800 ms) correlated with the two stimuli only for one button set but did not correlate with the buttons of the other set. Results show that on both button sets, responses were faster for frequent stimulus-foreperiod combinations than for infrequent ones. Thus, temporal expectancy generalizes over different effectors and response locations.