Temporal and spectral contributions to musical instrument identification and discrimination among cochlear implant users

Abstract

ObjectiveTo investigate the contributions of envelope and fine-structure to the perception of timbre by cochlear implant (CI) users as compared to normal hearing (NH) listeners.MethodsThis was a prospective cohort comparison study. Normal hearing and cochlear implant patients were tested. Three experiments were performed in sound field using musical notes altered to affect the characteristic pitch of an instrument and the acoustic envelope. Experiment 1 assessed the ability to identify the instrument playing each note, while experiments 2 and 3 assessed the ability to discriminate the different stimuli.ResultsNormal hearing subjects performed better than CI subjects in all instrument identification tasks, reaching statistical significance for 4 of 5 stimulus conditions. Within the CI population, acoustic envelope modifications did not significantly affect instrument identification or discrimination. With envelope and pitch cues removed, fine structure discrimination performance was similar between normal hearing and CI users for the majority of conditions, but some specific instrument comparisons were significantly more challenging for CI users.ConclusionsCochlear implant users perform significantly worse than normal hearing listeners on tasks of instrument identification. However, cochlear implant listeners can discriminate differences in envelope and some fine structure components of musical instrument sounds as well as normal hearing listeners. The results indicated that certain fine structure cues are important for cochlear implant users to make discrimination judgments, and therefore may affect interpretation toward associating with a specific instrument for identification.

Crucial Music Components Needed for Speech Perception Enhancement of Pediatric Cochlear Implant Users: A Systematic Review and Meta-Analysis

“…These results support past research findings that indicate CI users' rhythm perception improves better than other components of music after undergoing music training [Innes-Brown et al, 2013]. The finding shows that the CI processor able to convey rhythm fragments most accurately compared to other components [Limb, 2006;Prentiss et al, 2016]. It is so accurate that CI users could discriminate rhythmic pattern nearly like normal-hearing person (but exactly as good as normal-hearing listener) [Prentiss et al, 2016].…”

“…The finding shows that the CI processor able to convey rhythm fragments most accurately compared to other components [Limb, 2006;Prentiss et al, 2016]. It is so accurate that CI users could discriminate rhythmic pattern nearly like normal-hearing person (but exactly as good as normal-hearing listener) [Prentiss et al, 2016]. These research findings confirmed that rhythmic cues can be a primary factor for the successful processing of sound information when multiple cues exist, as in familiar melody recognition tasks [Galvin et al, 2007].…”

“…Furthermore, due to poor pitch perception by the CI user, the harmony cues related to pitch cues might not be conveyed properly to the auditory system [Knobloch et al, 2018]. Timbre, on the other hand, is the weakest and hardest music component to be learned by CI users as it contains both temporal envelope cues and mainly temporal fine structure cues that are well known to be of one the limitations of CI [Prentiss et al, 2016]. The result of this pooled analysis showed that timbre perception has the smallest improvement when compared to that of the other components (e.g., rhythm and pitch).…”

Enhanced Pitch Discrimination for Cochlear Implant Users with a New Haptic Neuroprosthetic

“…Impaired pitch discrimination also limits music perception 14 , as pitch conveys crucial melody, harmony, and tonality information. CI users struggle to recognise simple melodies [14][15][16][17] and to discriminate different instruments 14,18,19 with only around 13% of adult CI users reporting that they enjoy listening to music after implantation 20 .…”

“…Another way in which the mosaicOne_B could aid CI listening is by making it more robust to background noise. CI user performance degrades quickly when there are competing sounds; for example, CI users struggle to discriminate musical instruments when multiple instruments are playing 14,18,19 or to understand speech in noisy environments 21,22,30 , such as classrooms, busy workplaces, or cafes. A number of studies have shown that, in addition to impairing speech prosody perception, reduced access to information about changes in speech fundamental frequency (F 0 ; an acoustic correlate of pitch) reduces speech recognition in noise 37,38 .…”