Bilateral and bimodal cochlear implant listeners can segregate competing speech using talker sex cues, but not spatial cues

Abstract

Cochlear implant (CI) users have greater difficulty perceiving talker sex and spatial cues than do normal-hearing (NH) listeners. The present study measured recognition of target sentences in the presence of two co-located or spatially separated speech maskers in NH, bilateral CI, and bimodal CI listeners; masker sex was the same as or different than the target. NH listeners demonstrated a large masking release with masker sex and/or spatial cues. For CI listeners, significant masking release was observed with masker sex cues, but not with spatial cues, at least for the spatially symmetrically placed maskers and listening task used in this study.

Effects of tonotopic matching and spatial cues on segregation of competing speech in simulations of bilateral cochlear implants

“…The target sentence was always cued by the first word “John” and all five words were mutually exclusive among the target and masker sentences. A more detailed description regarding the test materials can be found in Xu et al [ 10 ] and Willis et al [ 19 ].…”

“…They found that spatial release from masking was poorer in bilateral CI users and in the bilateral CI simulations, compared to NH participants listening to unprocessed speech, similar to the effects of reducing the spectral resolution in Xu et al [ 10 ]. In fact, some studies have even reported negative spatial release from masking (i.e., poorer SRTs with dichotic than with diotic presentation) in bilateral CI users [ 19 , 20 ]. Presumably, poor spectral resolution limited the benefit of the spatial cues available during the segregation of competing speech.…”

Sex-mismatch benefit for speech-in-speech recognition by pediatric and adult cochlear implant users

“…The ability to benefit from a sex mismatch between target and masker speech has been consistently observed for children and adults who rely on acoustic hearing ( Brungart et al , 2001 ; Helfer and Freyman, 2008 ; Leibold et al , 2020 ), including listeners with hearing loss who wear hearing aids, but results for pediatric and adult CI users have been mixed ( Cullington and Zeng, 2008 ; El Boghdady et al , 2019 ; Meister et al , 2020 ; Stickney et al , 2004 ; Tao et al , 2018 ; Willis et al , 2021 ). The present experiment investigated the sex-mismatch benefit for pediatric and adult CI users using a two-male-talker and a two-female-talker masker, stimuli which have been shown to differ with respect to informational masking in normal-hearing adults ( Leibold et al , 2020 ).…”

“…Previous research on the sex-mismatch benefit for speech-in-speech recognition in CI users has produced mixed results. Some data indicate that CI users can benefit from a sex mismatch between target and masker speech ( Cullington and Zeng, 2008 ; Meister et al , 2020 ; Willis et al , 2021 ), although they do not benefit as much as listeners with normal hearing. In contrast, other data indicate no benefit of sex mismatch between target and masker talkers for CI users ( El Boghdady et al , 2019 ; Stickney et al , 2004 ).…”

Speech intelligibility and talker gender classification with noise-vocoded and tone-vocoded speech

“…Indeed, one study directly examining the effect of vocoding on the release from masking provided by different-gender talkers found that the benefit disappeared when speech was noise- or tone-vocoded into 15 channels ( Brungart et al , 2006 ). Furthermore, the degree of masking release provided by talker gender cues has also been examined in CI users, with the results indicating that these listeners can use acoustic cues related to talker gender to some extent ( Willis et al , 2021 ), but cannot categorize gender as well as non-CI listeners (e.g., Fu et al , 2005 ; Fuller et al , 2014 ).…”