Cochlear implant users' melody recognition with pitch and loudness cues

Abstract

Normal-hearing listeners can recognize familiar melodies from loudness changes, although more poorly than from pitch changes. Two hypotheses were tested here: (1) cochlear implant (CI) users can also use loudness changes to perceive melodic contours, and (2) their melody recognition can be enhanced with consistent pitch and loudness changes. In Experiment 1, melodic contours were created by changing the F0s of harmonic complex tones, by changing the intensities of broadband noise bursts, or both. In Experiment 2, familiar melodies were recorded by a pianist. The note intensities were kept as recorded, equalized at 70 dB SPL, or changed from 45 to 75 dB SPL to match the relative pitch changes in semitones. Loudness melodies were also generated with intensity-changing noise bursts. The results showed that CI users' melodic contour identification was better with both pitch and loudness changes than with either alone. Specifically, adding loudness changes significantly improved identification of melodic conto...