Pitch contour perception in speech and music at accelerated speed in hearing-impaired seniors

Authors: Yohan Villalon1, Yohana Lévêque1, Etienne Gaudrain1

1Psychoacoustic and Auditory Cognition team, Lyon Neuroscience Research Center, Université Lyon

Background: Pitch contours play a central role in the perception of intonation in speech and a crucial role in the structure, expression and emotional meaning of music. While static pitch perception seems preserved in case of hearing loss, the perception of dynamic pitch contours may be hindered. This study aims to determine whether acceleration is more detrimental to pitch contour discrimination in individuals with hearing impairments than normal-hearing individuals compared to normal speed condition.

Method: Participants performed a pitch contour discrimination task using (1) FraMatrix sentences and (2) sung melodies. In both cases, in each trial, the participants were presented with two identical stimuli, except for a local pitch contour alteration, and had to judge whether they were identical or different. For the sentences, the pitch contour alteration applied to a single word, and consisted in an increase of 0, 2.5 or 3.5 semitones (st). For the melodies, the alteration concerned a single note and was made to be musically relevant. For both conditions, an acceleration of 25% was applied to half of the trials. All the stimuli were low-pass filtered below 3 kHz to ensure that none of the participants had access to high frequency information.

Results: Preliminary results indicate that hearing-impaired listeners showed greater deterioration in pitch contour detection with accelerated speech at 2.5 st compared to controls. At 3.5 st, both groups showed declining performance with acceleration. The music task showed no significant differences across groups, and with and without acceleration.

Conclusion: The findings support the hypothesis that fast speech degrades pitch discrimination more for individuals with hearing loss than for those with normal hearing. Our results suggest hearing impairment is associated with pitch discrimination degradation in a dynamic context like speech, but pitch contour processing in music did not seem to be altered by a speed change.