Change deafness for simultaneous voices

Apparent changes in auditory scenes are often unnoticed. This change deafness phenomenon was examined in auditory scenes that comprise human voices. In two experiments, listeners were required to detect changes between two auditory scenes comprising two, three, and four talkers who voiced four‐syllable words. One of the voices in the first scene was randomly selected and was replaced with a new word in change trials. The rationale was that higher stimulus familiarity conferred by human voices compared to other everyday sounds, together with encoding and memory advantages for verbal stimuli and the modular processing of speech in auditory processing, should positively influence the change detection efficiency, and the change deafness phenomenon should not be observed when listeners are explicitly required to detect the obvious changes. Contrary to the prediction, change deafness was significantly observed in three‐ and four‐talker conditions. This indicates that change deafness occurs in listeners even for highly familiar stimuli. This suggests the limited ability for perceptual organization of auditory scenes comprising even a relatively small number of voices (three or four).