Synchronization of unimanual and bimanual responses with monotic and dichotic clicks

In experiments requiring subjective judgments, the apparent rate of rapidly presented dichotically alternating clicks has consistently been shown to be slower than that of clicks presented monotically. The first of the present studies asked (1) if slowing of dichotic clicks would be observed when the listener’s task was to “follow” the clicks with overt motor responses (unimanual keypresses) rather than to make psychophysical judgments, and (2) if following of dichotic clicks could be improved by providing two response channels (alternating bimanual presses). Both answers were affirmative. The second study asked (3) if the improvement obtained in the bimanual condition reflected increased perceptual capacity. The results indicated that it did not, but was attributable to an increase in response ceiling.