Pitch ranking of complex tones by normally hearing subjects and cochlear implant users

Abstract

The ability of 10 normally hearing (NH) adults and eight cochlear implant (CI) users to pitch-rank pairs of complex tones was assessed. The acoustically presented stimuli differed in fundamental frequency (F0) by either one or six semitones (F0 range: 98 to 740 Hz). The NH group obtained significantly higher mean scores for both experiments: (NH: one semitone - 81.2%, six semitones - 89.0%; CI: one semitone - 49.0%, six semitones - 60.2%; p<0.001). Prior musical experience was found to be associated with higher pitch-ranking scores for the NH subjects. Those with musical experience ratings <3 obtained significantly lower scores for both interval sizes (p<0.001) than those with higher ratings. Nevertheless, the scores obtained by the musically inexperienced, NH adults were significantly higher than those obtained by the CI group for both the one-semitone (p=0.022) and six-semitone (p=0.018) intervals. These results suggest that the pitch information CI users obtain from their implant systems is less accurate than that obtained by NH listeners when listening to the same complex sounds. Furthermore, the relatively poor pitch-ranking ability of at least some CI users may be associated with a more-limited experience of music in general.