Preferred recall order and recall accuracy for two messages presented simultaneously over a single auditory channel

Ss in the dichotic listening task prefer, and are more accurate with, the channel-by-channel order of recall-recalling all information presented to one ear followed by the information presented to the other ear. Current explanations for these effects rely upon the fact that the two messages are presented over separate input channels. The present study tested this hypothesis directly by presenting two messages simultaneously to a single auditory channel. Groups of Ss were instructed to recall two pairs of digits presented simultaneously over a single channel (1) in any order (free recall), (2) in the order received (simultaneous order), or (3) in sequential groups (successive order). Ss in the free recall task preferred recalling items in successive order. However, Ss instructed to recall in simultaneous order were as accurate as those instructed to recall in successive order. These data imply that accuracy with, but not preference for, the successive order of recall depends upon whether input is to one or two channels.