Perceiving Surprising Words in an Unattended Auditory Channel

This study addresses two related issues, the degree to which unattended auditory material is interpreted, and the processes by which the direction of attention is controlled. Subjects shadowed a prose passage presented to the right ear while an irrelevant list of names was presented to the left ear. At three points the list of names underwent an abrupt semantic change. When shadowing was stopped and the subjects were asked to recall left-channel material, recall was significantly better after changes than after control material not involving a change. There was a corresponding increase in shadowing errors at each locus of change. These results indicate that unattended material is processed to the semantic level and that change is among the factors which control the deployment of attention.