Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise
ABSTRACT Purpose The inter-aural time difference (ITD) and inter-aural level difference (ILD) are important acoustic cues for horizontal localization and spatial release from masking. These cues are encoded based on inter-aural comparisons of tonotopically matched binaural inputs. Therefore, binaur...
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| Format: | Article |
| Language: | English |
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Sociedade Brasileira de Fonoaudiologia
2024-02-01
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| Series: | CoDAS |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-17822024000200310&tlng=en |
| _version_ | 1797323532066095104 |
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| author | Vibha Kanagokar Hasna Fathima Jayashree Sunil Bhat Arivudai Nambi Pitchai Muthu |
| author_facet | Vibha Kanagokar Hasna Fathima Jayashree Sunil Bhat Arivudai Nambi Pitchai Muthu |
| author_sort | Vibha Kanagokar |
| collection | DOAJ |
| description | ABSTRACT Purpose The inter-aural time difference (ITD) and inter-aural level difference (ILD) are important acoustic cues for horizontal localization and spatial release from masking. These cues are encoded based on inter-aural comparisons of tonotopically matched binaural inputs. Therefore, binaural coherence or the interaural spectro-temporal similarity is a pre-requisite for encoding ITD and ILD. The modulation depth of envelope is an important envelope characteristic that helps in encoding the envelope-ITD. However, inter-aural difference in modulation depth can result in reduced binaural coherence and poor representation of binaural cues as in the case with reverberation, noise and compression in cochlear implants and hearing aids. This study investigated the effect of inter-aural modulation depth difference on the ITD thresholds for an amplitude-modulated noise in normal hearing young adults. Methods An amplitude modulated high pass filtered noise with varying modulation depth differences was presented sequentially through headphones. In one ear, the modulation depth was retained at 90% and in the other ear it varied from 90% to 50%. The ITD thresholds for modulation frequencies of 8 Hz and 16 Hz were estimated as a function of the inter-aural modulation depth difference. Results The Friedman test findings revealed a statistically significant increase in the ITD threshold with an increase in the inter-aural modulation depth difference for 8 Hz and 16 Hz. Conclusion The results indicate that the inter-aural differences in the modulation depth negatively impact ITD perception for an amplitude-modulated high pass filtered noise. |
| first_indexed | 2024-03-08T05:30:02Z |
| format | Article |
| id | doaj.art-829b8a6f911b455a8bb2019efccc56db |
| institution | Directory Open Access Journal |
| issn | 2317-1782 |
| language | English |
| last_indexed | 2024-03-08T05:30:02Z |
| publishDate | 2024-02-01 |
| publisher | Sociedade Brasileira de Fonoaudiologia |
| record_format | Article |
| series | CoDAS |
| spelling | doaj.art-829b8a6f911b455a8bb2019efccc56db2024-02-06T07:40:20ZengSociedade Brasileira de FonoaudiologiaCoDAS2317-17822024-02-0136210.1590/2317-1782/20232022261Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noiseVibha Kanagokarhttps://orcid.org/0000-0003-1483-4690Hasna Fathimahttps://orcid.org/0000-0001-6573-5380Jayashree Sunil Bhathttps://orcid.org/0000-0003-4706-1591Arivudai Nambi Pitchai Muthuhttps://orcid.org/0000-0001-7399-5334ABSTRACT Purpose The inter-aural time difference (ITD) and inter-aural level difference (ILD) are important acoustic cues for horizontal localization and spatial release from masking. These cues are encoded based on inter-aural comparisons of tonotopically matched binaural inputs. Therefore, binaural coherence or the interaural spectro-temporal similarity is a pre-requisite for encoding ITD and ILD. The modulation depth of envelope is an important envelope characteristic that helps in encoding the envelope-ITD. However, inter-aural difference in modulation depth can result in reduced binaural coherence and poor representation of binaural cues as in the case with reverberation, noise and compression in cochlear implants and hearing aids. This study investigated the effect of inter-aural modulation depth difference on the ITD thresholds for an amplitude-modulated noise in normal hearing young adults. Methods An amplitude modulated high pass filtered noise with varying modulation depth differences was presented sequentially through headphones. In one ear, the modulation depth was retained at 90% and in the other ear it varied from 90% to 50%. The ITD thresholds for modulation frequencies of 8 Hz and 16 Hz were estimated as a function of the inter-aural modulation depth difference. Results The Friedman test findings revealed a statistically significant increase in the ITD threshold with an increase in the inter-aural modulation depth difference for 8 Hz and 16 Hz. Conclusion The results indicate that the inter-aural differences in the modulation depth negatively impact ITD perception for an amplitude-modulated high pass filtered noise.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-17822024000200310&tlng=enInter-Aural Time DifferenceModulation DepthInter-Aural Modulation Depth DifferenceModulation FrequencyEnvelope |
| spellingShingle | Vibha Kanagokar Hasna Fathima Jayashree Sunil Bhat Arivudai Nambi Pitchai Muthu Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise CoDAS Inter-Aural Time Difference Modulation Depth Inter-Aural Modulation Depth Difference Modulation Frequency Envelope |
| title | Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise |
| title_full | Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise |
| title_fullStr | Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise |
| title_full_unstemmed | Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise |
| title_short | Effect of inter-aural temporal envelope differences on inter-aural time difference thresholds for amplitude modulated noise |
| title_sort | effect of inter aural temporal envelope differences on inter aural time difference thresholds for amplitude modulated noise |
| topic | Inter-Aural Time Difference Modulation Depth Inter-Aural Modulation Depth Difference Modulation Frequency Envelope |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-17822024000200310&tlng=en |
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