Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction
In cochlear implants (CI), spread of neural excitation may produce channel interaction. Channel interaction disturbs the spectral resolution and, among other factors, seems to impair speech recognition, especially in noise. In this study, two tests were performed with 20 adult normal-hearing (NH) su...
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| Format: | Article |
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MDPI AG
2021-02-01
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| Series: | Journal of Clinical Medicine |
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| Online Access: | https://www.mdpi.com/2077-0383/10/4/679 |
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| author | Pierre-Antoine Cucis Christian Berger-Vachon Hung Thaï-Van Ruben Hermann Stéphane Gallego Eric Truy |
| author_facet | Pierre-Antoine Cucis Christian Berger-Vachon Hung Thaï-Van Ruben Hermann Stéphane Gallego Eric Truy |
| author_sort | Pierre-Antoine Cucis |
| collection | DOAJ |
| description | In cochlear implants (CI), spread of neural excitation may produce channel interaction. Channel interaction disturbs the spectral resolution and, among other factors, seems to impair speech recognition, especially in noise. In this study, two tests were performed with 20 adult normal-hearing (NH) subjects under different vocoded simulations. First, there was a measurement of word recognition in noise while varying the number of selected channels (4, 8, 12 or 16 maxima out of 20) and the degree of simulated channel interaction (“Low”, “Medium” and “High”). Then, there was an evaluation of spectral resolution function of the degree of simulated channel interaction, reflected by the sharpness (Q10dB) of psychophysical tuning curves (PTCs). The results showed a significant effect of the simulated channel interaction on word recognition but did not find an effect of the number of selected channels. The intelligibility decreased significantly for the highest degree of channel interaction. Similarly, the highest simulated channel interaction impaired significantly the Q10dB. Additionally, a strong intra-individual correlation between frequency selectivity and word recognition in noise was observed. Lastly, the individual changes in frequency selectivity were positively correlated with the changes in word recognition when the degree of interaction went from “Low” to “High”. To conclude, the degradation seen for the highest degree of channel interaction suggests a threshold effect on frequency selectivity and word recognition. The correlation between frequency selectivity and intelligibility in noise supports the hypothesis that PTCs Q10dB can account for word recognition in certain conditions. Moreover, the individual variations of performances observed among subjects suggest that channel interaction does not have the same effect on each individual. Finally, these results highlight the importance of taking into account subjects’ individuality and to evaluate channel interaction through the speech processor. |
| first_indexed | 2024-03-09T04:53:21Z |
| format | Article |
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| issn | 2077-0383 |
| language | English |
| last_indexed | 2024-03-09T04:53:21Z |
| publishDate | 2021-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Clinical Medicine |
| spelling | doaj.art-bd6fe270bf474f63ba2df090cf6ad0942023-12-03T13:08:47ZengMDPI AGJournal of Clinical Medicine2077-03832021-02-0110467910.3390/jcm10040679Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel InteractionPierre-Antoine Cucis0Christian Berger-Vachon1Hung Thaï-Van2Ruben Hermann3Stéphane Gallego4Eric Truy5Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, CRNL Inserm U1028, CNRS UMR5292, 69675 Bron, FranceClaude Bernard Lyon 1 University, 69100 Villeurbanne, FranceClaude Bernard Lyon 1 University, 69100 Villeurbanne, FranceIntegrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, CRNL Inserm U1028, CNRS UMR5292, 69675 Bron, FranceClaude Bernard Lyon 1 University, 69100 Villeurbanne, FranceIntegrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, CRNL Inserm U1028, CNRS UMR5292, 69675 Bron, FranceIn cochlear implants (CI), spread of neural excitation may produce channel interaction. Channel interaction disturbs the spectral resolution and, among other factors, seems to impair speech recognition, especially in noise. In this study, two tests were performed with 20 adult normal-hearing (NH) subjects under different vocoded simulations. First, there was a measurement of word recognition in noise while varying the number of selected channels (4, 8, 12 or 16 maxima out of 20) and the degree of simulated channel interaction (“Low”, “Medium” and “High”). Then, there was an evaluation of spectral resolution function of the degree of simulated channel interaction, reflected by the sharpness (Q10dB) of psychophysical tuning curves (PTCs). The results showed a significant effect of the simulated channel interaction on word recognition but did not find an effect of the number of selected channels. The intelligibility decreased significantly for the highest degree of channel interaction. Similarly, the highest simulated channel interaction impaired significantly the Q10dB. Additionally, a strong intra-individual correlation between frequency selectivity and word recognition in noise was observed. Lastly, the individual changes in frequency selectivity were positively correlated with the changes in word recognition when the degree of interaction went from “Low” to “High”. To conclude, the degradation seen for the highest degree of channel interaction suggests a threshold effect on frequency selectivity and word recognition. The correlation between frequency selectivity and intelligibility in noise supports the hypothesis that PTCs Q10dB can account for word recognition in certain conditions. Moreover, the individual variations of performances observed among subjects suggest that channel interaction does not have the same effect on each individual. Finally, these results highlight the importance of taking into account subjects’ individuality and to evaluate channel interaction through the speech processor.https://www.mdpi.com/2077-0383/10/4/679vocoder simulationnormal-hearingspread of excitationcochlear implantspeech in noise |
| spellingShingle | Pierre-Antoine Cucis Christian Berger-Vachon Hung Thaï-Van Ruben Hermann Stéphane Gallego Eric Truy Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction Journal of Clinical Medicine vocoder simulation normal-hearing spread of excitation cochlear implant speech in noise |
| title | Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction |
| title_full | Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction |
| title_fullStr | Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction |
| title_full_unstemmed | Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction |
| title_short | Word Recognition and Frequency Selectivity in Cochlear Implant Simulation: Effect of Channel Interaction |
| title_sort | word recognition and frequency selectivity in cochlear implant simulation effect of channel interaction |
| topic | vocoder simulation normal-hearing spread of excitation cochlear implant speech in noise |
| url | https://www.mdpi.com/2077-0383/10/4/679 |
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