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Buth S, Baljić I, Mewes A, Hey M. [Speech discrimination with separated signal sources and sound localization with speech stimuli : Learning effects and reproducibility]. HNO 2024; 72:504-514. [PMID: 38536465 PMCID: PMC11192817 DOI: 10.1007/s00106-024-01426-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2023] [Indexed: 06/22/2024]
Abstract
BACKGROUND Binaural hearing enables better speech comprehension in noisy environments and is necessary for acoustic spatial orientation. This study investigates speech discrimination in noise with separated signal sources and measures sound localization. The aim was to study characteristics and reproducibility of two selected measurement techniques which seem to be suitable for description of the aforementioned aspects of binaural hearing. MATERIALS AND METHODS Speech reception thresholds (SRT) in noise and test-retest reliability were collected from 55 normal-hearing adults for a spatial setup of loudspeakers with angles of ± 45° and ± 90° using the Oldenburg sentence test. The investigations of sound localization were conducted in a semicircle and fullcircle setup (7 and 12 equidistant loudspeakers). RESULTS SRT (S-45N45: -14.1 dB SNR; S45N-45: -16.4 dB SNR; S0N90: -13.1 dB SNR; S0N-90: -13.4 dB SNR) and test-retest reliability (4 to 6 dB SNR) were collected for speech intelligibility in noise with separated signals. The procedural learning effect for this setup could only be mitigated with 120 training sentences. Significantly smaller SRT values, resulting in better speech discrimination, were found for the test situation of the right compared to the left ear. RMS values could be gathered for sound localization in the semicircle (1,9°) as well as in the fullcircle setup (11,1°). Better results were obtained in the retest of the fullcircle setup. CONCLUSION When using the Oldenburg sentence test in noise with spatially separated signals, it is mandatory to perform a training session of 120 sentences in order to minimize the procedural learning effect. Ear-specific SRT values for speech discrimination in noise with separated signal sources are required, which is probably due to the right-ear advantage. A training is recommended for sound localization in the fullcircle setup.
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Affiliation(s)
- Svenja Buth
- Medizinische Fakultät, Christian-Albrechts-Universität zu Kiel, Kiel, Deutschland.
- HNO-Klinik, Audiologie, Campus Kiel, Universitätsklinikum Schleswig-Holstein, Arnold-Heller-Str. 3, Haus B1, 24105, Kiel, Deutschland.
| | - Izet Baljić
- Klinik für Hals‑, Nasen‑, Ohrenheilkunde, Audiologisches Zentrum, Helios Klinikum Erfurt, Erfurt, Deutschland
| | - Alexander Mewes
- Klinik für Hals‑, Nasen‑, Ohrenheilkunde, Kopf- und Halschirurgie, Audiologie, UKSH, Kiel, Deutschland
| | - Matthias Hey
- Klinik für Hals‑, Nasen‑, Ohrenheilkunde, Kopf- und Halschirurgie, Audiologie, UKSH, Kiel, Deutschland
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Valzolgher C. Motor Strategies: The Role of Active Behavior in Spatial Hearing Research. Psychol Rep 2024:332941241260246. [PMID: 38857521 DOI: 10.1177/00332941241260246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
When completing a task, the ability to implement behavioral strategies to solve it in an effective and cognitively less-demanding way is extremely adaptive for humans. This behavior makes it possible to accumulate evidence and test one's own predictions about the external world. In this work, starting from examples in the field of spatial hearing research, I analyze the importance of considering motor strategies in perceptual tasks, and I stress the urgent need to create ecological experimental settings, which are essential in allowing the implementation of such behaviors and in measuring them. In particular, I will consider head movements as an example of strategic behavior implemented to solve acoustic space-perception tasks.
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Affiliation(s)
- Chiara Valzolgher
- Center for Mind/Brain Sciences, University of Trento, Rovereto, Italy
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3
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Hu H, Ewert SD, Kollmeier B, Vickers D. Rate dependent neural responses of interaural-time-difference cues in fine-structure and envelope. PeerJ 2024; 12:e17104. [PMID: 38680894 PMCID: PMC11055513 DOI: 10.7717/peerj.17104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 02/22/2024] [Indexed: 05/01/2024] Open
Abstract
Advancements in cochlear implants (CIs) have led to a significant increase in bilateral CI users, especially among children. Yet, most bilateral CI users do not fully achieve the intended binaural benefit due to potential limitations in signal processing and/or surgical implant positioning. One crucial auditory cue that normal hearing (NH) listeners can benefit from is the interaural time difference (ITD), i.e., the time difference between the arrival of a sound at two ears. The ITD sensitivity is thought to be heavily relying on the effective utilization of temporal fine structure (very rapid oscillations in sound). Unfortunately, most current CIs do not transmit such true fine structure. Nevertheless, bilateral CI users have demonstrated sensitivity to ITD cues delivered through envelope or interaural pulse time differences, i.e., the time gap between the pulses delivered to the two implants. However, their ITD sensitivity is significantly poorer compared to NH individuals, and it further degrades at higher CI stimulation rates, especially when the rate exceeds 300 pulse per second. The overall purpose of this research thread is to improve spatial hearing abilities in bilateral CI users. This study aims to develop electroencephalography (EEG) paradigms that can be used with clinical settings to assess and optimize the delivery of ITD cues, which are crucial for spatial hearing in everyday life. The research objective of this article was to determine the effect of CI stimulation pulse rate on the ITD sensitivity, and to characterize the rate-dependent degradation in ITD perception using EEG measures. To develop protocols for bilateral CI studies, EEG responses were obtained from NH listeners using sinusoidal-amplitude-modulated (SAM) tones and filtered clicks with changes in either fine structure ITD (ITDFS) or envelope ITD (ITDENV). Multiple EEG responses were analyzed, which included the subcortical auditory steady-state responses (ASSRs) and cortical auditory evoked potentials (CAEPs) elicited by stimuli onset, offset, and changes. Results indicated that acoustic change complex (ACC) responses elicited by ITDENV changes were significantly smaller or absent compared to those elicited by ITDFS changes. The ACC morphologies evoked by ITDFS changes were similar to onset and offset CAEPs, although the peak latencies were longest for ACC responses and shortest for offset CAEPs. The high-frequency stimuli clearly elicited subcortical ASSRs, but smaller than those evoked by lower carrier frequency SAM tones. The 40-Hz ASSRs decreased with increasing carrier frequencies. Filtered clicks elicited larger ASSRs compared to high-frequency SAM tones, with the order being 40 > 160 > 80> 320 Hz ASSR for both stimulus types. Wavelet analysis revealed a clear interaction between detectable transient CAEPs and 40-Hz ASSRs in the time-frequency domain for SAM tones with a low carrier frequency.
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Affiliation(s)
- Hongmei Hu
- SOUND Lab, Cambridge Hearing Group, Department of Clinical Neuroscience, Cambridge University, Cambridge, United Kingdom
- Department of Medical Physics and Acoustics, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Stephan D. Ewert
- Department of Medical Physics and Acoustics, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Birger Kollmeier
- Department of Medical Physics and Acoustics, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Deborah Vickers
- SOUND Lab, Cambridge Hearing Group, Department of Clinical Neuroscience, Cambridge University, Cambridge, United Kingdom
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Chen B, Zhang X, Chen J, Shi Y, Zou X, Liu P, Li Y, Galvin JJ, Fu QJ. Tonal language experience facilitates the use of spatial cues for segregating competing speech in bimodal cochlear implant listeners. JASA EXPRESS LETTERS 2024; 4:034401. [PMID: 38426890 PMCID: PMC10926108 DOI: 10.1121/10.0025058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 02/09/2024] [Indexed: 03/02/2024]
Abstract
English-speaking bimodal and bilateral cochlear implant (CI) users can segregate competing speech using talker sex cues but not spatial cues. While tonal language experience allows for greater utilization of talker sex cues for listeners with normal hearing, tonal language benefits remain unclear for CI users. The present study assessed the ability of Mandarin-speaking bilateral and bimodal CI users to recognize target sentences amidst speech maskers that varied in terms of spatial cues and/or talker sex cues, relative to the target. Different from English-speaking CI users, Mandarin-speaking CI users exhibited greater utilization of spatial cues, particularly in bimodal listening.
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Affiliation(s)
- Biao Chen
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Xinyi Zhang
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Jingyuan Chen
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Ying Shi
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Xinyue Zou
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Ping Liu
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - Yongxin Li
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Ministry of Education of China, Beijing, People's Republic of China
| | - John J Galvin
- House Institute Foundation, Los Angeles, California 90057, USA
| | - Qian-Jie Fu
- Department of Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, , , , , , , , ,
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Valzolgher C, Bouzaid S, Grenouillet S, Gatel J, Ratenet L, Murenu F, Verdelet G, Salemme R, Gaveau V, Coudert A, Hermann R, Truy E, Farnè A, Pavani F. Training spatial hearing in unilateral cochlear implant users through reaching to sounds in virtual reality. Eur Arch Otorhinolaryngol 2023; 280:3661-3672. [PMID: 36905419 PMCID: PMC10313844 DOI: 10.1007/s00405-023-07886-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 02/13/2023] [Indexed: 03/12/2023]
Abstract
BACKGROUND AND PURPOSE Use of unilateral cochlear implant (UCI) is associated with limited spatial hearing skills. Evidence that training these abilities in UCI user is possible remains limited. In this study, we assessed whether a Spatial training based on hand-reaching to sounds performed in virtual reality improves spatial hearing abilities in UCI users METHODS: Using a crossover randomized clinical trial, we compared the effects of a Spatial training protocol with those of a Non-Spatial control training. We tested 17 UCI users in a head-pointing to sound task and in an audio-visual attention orienting task, before and after each training. Study is recorded in clinicaltrials.gov (NCT04183348). RESULTS During the Spatial VR training, sound localization errors in azimuth decreased. Moreover, when comparing head-pointing to sounds before vs. after training, localization errors decreased after the Spatial more than the control training. No training effects emerged in the audio-visual attention orienting task. CONCLUSIONS Our results showed that sound localization in UCI users improves during a Spatial training, with benefits that extend also to a non-trained sound localization task (generalization). These findings have potentials for novel rehabilitation procedures in clinical contexts.
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Affiliation(s)
- Chiara Valzolgher
- Center for Mind/Brain Sciences (CIMeC), University of Trento, Corso Bettini, 31 Rovereto, Trento, Italy.
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France.
| | - Sabrina Bouzaid
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
| | - Solene Grenouillet
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
| | | | | | - Francesca Murenu
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
| | - Grégoire Verdelet
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
- Neuroimmersion, Lyon, France
| | - Romeo Salemme
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
- Neuroimmersion, Lyon, France
| | - Valérie Gaveau
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
| | | | | | - Eric Truy
- Hospices Civils de Lyon, Lyon, France
| | - Alessandro Farnè
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
- Neuroimmersion, Lyon, France
| | - Francesco Pavani
- Center for Mind/Brain Sciences (CIMeC), University of Trento, Corso Bettini, 31 Rovereto, Trento, Italy
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, University of Lyon 1, Lyon, France
- Centro Interuniversitario di Ricerca "Cognizione, Linguaggio e Sordità" (CIRCLeS), Trento, Italy
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Dennison SR, Thakkar T, Kan A, Litovsky RY. Lateralization of binaural envelope cues measured with a mobile cochlear-implant research processora). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:3543-3558. [PMID: 37390320 PMCID: PMC10314808 DOI: 10.1121/10.0019879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 07/02/2023]
Abstract
Bilateral cochlear implant (BICI) listeners do not have full access to the binaural cues that normal hearing (NH) listeners use for spatial hearing tasks such as localization. When using their unsynchronized everyday processors, BICI listeners demonstrate sensitivity to interaural level differences (ILDs) in the envelopes of sounds, but interaural time differences (ITDs) are less reliably available. It is unclear how BICI listeners use combinations of ILDs and envelope ITDs, and how much each cue contributes to perceived sound location. The CCi-MOBILE is a bilaterally synchronized research processor with the untested potential to provide spatial cues to BICI listeners. In the present study, the CCi-MOBILE was used to measure the ability of BICI listeners to perceive lateralized sound sources when single pairs of electrodes were presented amplitude-modulated stimuli with combinations of ILDs and envelope ITDs. Young NH listeners were also tested using amplitude-modulated high-frequency tones. A cue weighting analysis with six BICI and ten NH listeners revealed that ILDs contributed more than envelope ITDs to lateralization for both groups. Moreover, envelope ITDs contributed to lateralization for NH listeners but had negligible contribution for BICI listeners. These results suggest that the CCi-MOBILE is suitable for binaural testing and developing bilateral processing strategies.
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Affiliation(s)
| | - Tanvi Thakkar
- University of Wisconsin-La Crosse, La Crosse, Wisconsin 54601, USA
| | - Alan Kan
- Macquarie University, Macquarie Park, New South Wales, Australia
| | - Ruth Y Litovsky
- University of Wisconsin-Madison, Madison, Wisconsin 53711, USA
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Ghosh R, Hansen JHL. Bilateral Cochlear Implant Processing of Coding Strategies With CCi-MOBILE, an Open-Source Research Platform. IEEE/ACM TRANSACTIONS ON AUDIO, SPEECH, AND LANGUAGE PROCESSING 2023; 31:1839-1850. [PMID: 38046574 PMCID: PMC10691824 DOI: 10.1109/taslp.2023.3267608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
While speech understanding for cochlear implant (CI) users in quiet is relatively effective, listeners experience difficulty in identification of speaker and sound location. To assist for better residual hearing abilities and speech intelligibility support, bilateral and bimodal forms of assisted hearing is becoming popular among CI users. Effective bilateral processing calls for testing precise algorithm synchronization and fitting between both left and right ear channels in order to capture interaural time and level difference cues (ITD and ILDs). This work demonstrates bilateral implant algorithm processing using a custom-made CI research platform - CCi-MOBILE, which is capable of capturing precise source localization information and supports researchers in testing bilateral CI processing in real-time naturalistic environments. Simulation-based, objective, and subjective testing has been performed to validate the accuracy of the platform. The subjective test results produced an RMS error of ±8.66° for source localization, which is comparable to the performance of commercial CI processors.
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Affiliation(s)
- Ria Ghosh
- Center for Robust Speech Systems, CILab - Cochlear Implant Processing Lab, Department of Electrical and Computer Engineering, University of Texas at Dallas, Richardson, TX 75080 USA
| | - John H L Hansen
- Center for Robust Speech Systems, CILab - Cochlear Implant Processing Lab, Department of Electrical and Computer Engineering, Erik Jonsson School of Engineering and Computer Science, University of Texas at Dallas, Richardson, TX 75080 USA, and also with the School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080 USA
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Kırbaç A, Kaynakoğlu B, ASLAN F, İncesulu A. Effects of Unilateral Audio-Vestibular Insufficiency on Spatial Hearing. Indian J Otolaryngol Head Neck Surg 2023; 75:313-319. [PMID: 37206850 PMCID: PMC10188835 DOI: 10.1007/s12070-022-03442-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/25/2022] [Indexed: 01/09/2023] Open
Abstract
This study aimed to compare spatial hearing performance between adult individuals with the unilateral sensorineural hearing loss and unilateral loss of horizontal semicircular canal function (termed canal paresis/weakness) in the same ear and adults with normal hearing thresholds and normal vestibular function and to examine associated factors (duration of hearing loss and rate of canal paresis).The study participants consisted of 20 adults (aged 48±11 years) with unilateral sensorineural hearing loss and unilateral canal paresis (unilateral weakness≥25%) in the same ear. The control group comprised 25 adults (aged 45±13 years) with normal hearing and a unilateral weakness rate below 25%. Pure tone audiometry, bithermal binaural air caloric test, Turkish Spatial Hearing Questionnaire (T-SHQ), and Standardized Mini-Mental State Exam were applied to all the individuals. When the performance of the participants in T-SHQ was examined both in terms of the subscales and the total scale, there was a statistically significant difference between the two groups in relation to the scores. A statistically significant, high, negative correlation was detected between the duration of hearing loss, the rate of canal paresis and all the subscale scores and total score of T-SHQ. According to these results, as the duration of hearing loss increased, the scores obtained from the questionnaire decreased. As the rate of canal paresis increased, vestibular involvement increased, and the T-SHQ score decreased. This study showed that adults with unilateral hearing loss and unilateral canal paresis in the same ear had lower spatial hearing performance than those with normal hearing and balance. Supplementary Information The online version contains supplementary material available at 10.1007/s12070-022-03442-1.
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Affiliation(s)
- Arzu Kırbaç
- Faculty of Health Sciences, Department of Audiology, Eskişehir Osmangazi University, Eskişehir, Türkiye
| | - Büşra Kaynakoğlu
- Health Science Faculty, Department of Audiology, Selçuk University, Konya, Türkiye
| | - Filiz ASLAN
- Health Science Faculty, Department of Audiology, Hacettepe University, Ankara, Turkey
| | - Armağan İncesulu
- Faculty of Medicine, Department of Otolaryngology, Eskisehir Osmangazi University, Eskişehir, Türkiye
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Abstract
OBJECTIVES We assessed if spatial hearing training improves sound localization in bilateral cochlear implant (BCI) users and whether its benefits can generalize to untrained sound localization tasks. DESIGN In 20 BCI users, we assessed the effects of two training procedures (spatial versus nonspatial control training) on two different tasks performed before and after training (head-pointing to sound and audiovisual attention orienting). In the spatial training, participants identified sound position by reaching toward the sound sources with their hand. In the nonspatial training, comparable reaching movements served to identify sound amplitude modulations. A crossover randomized design allowed comparison of training procedures within the same participants. Spontaneous head movements while listening to the sounds were allowed and tracked to correlate them with localization performance. RESULTS During spatial training, BCI users reduced their sound localization errors in azimuth and adapted their spontaneous head movements as a function of sound eccentricity. These effects generalized to the head-pointing sound localization task, as revealed by greater reduction of sound localization error in azimuth and more accurate first head-orienting response, as compared to the control nonspatial training. BCI users benefited from auditory spatial cues for orienting visual attention, but the spatial training did not enhance this multisensory attention ability. CONCLUSIONS Sound localization in BCI users improves with spatial reaching-to-sound training, with benefits to a nontrained sound localization task. These findings pave the way to novel rehabilitation procedures in clinical contexts.
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Sheffield SW, Wheeler HJ, Brungart DS, Bernstein JGW. The Effect of Sound Localization on Auditory-Only and Audiovisual Speech Recognition in a Simulated Multitalker Environment. Trends Hear 2023; 27:23312165231186040. [PMID: 37415497 PMCID: PMC10331332 DOI: 10.1177/23312165231186040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/13/2023] [Accepted: 06/17/2023] [Indexed: 07/08/2023] Open
Abstract
Information regarding sound-source spatial location provides several speech-perception benefits, including auditory spatial cues for perceptual talker separation and localization cues to face the talker to obtain visual speech information. These benefits have typically been examined separately. A real-time processing algorithm for sound-localization degradation (LocDeg) was used to investigate how spatial-hearing benefits interact in a multitalker environment. Normal-hearing adults performed auditory-only and auditory-visual sentence recognition with target speech and maskers presented from loudspeakers at -90°, -36°, 36°, or 90° azimuths. For auditory-visual conditions, one target and three masking talker videos (always spatially separated) were rendered virtually in rectangular windows at these locations on a head-mounted display. Auditory-only conditions presented blank windows at these locations. Auditory target speech (always spatially aligned with the target video) was presented in co-located speech-shaped noise (experiment 1) or with three co-located or spatially separated auditory interfering talkers corresponding to the masker videos (experiment 2). In the co-located conditions, the LocDeg algorithm did not affect auditory-only performance but reduced target orientation accuracy, reducing auditory-visual benefit. In the multitalker environment, two spatial-hearing benefits were observed: perceptually separating competing speech based on auditory spatial differences and orienting to the target talker to obtain visual speech cues. These two benefits were additive, and both were diminished by the LocDeg algorithm. Although visual cues always improved performance when the target was accurately localized, there was no strong evidence that they provided additional assistance in perceptually separating co-located competing speech. These results highlight the importance of sound localization in everyday communication.
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Affiliation(s)
- Sterling W. Sheffield
- Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, FL, USA
| | - Harley J. Wheeler
- Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN, USA
| | - Douglas S. Brungart
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - Joshua G. W. Bernstein
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD, USA
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Burg EA, Thakkar TD, Litovsky RY. Interaural speech asymmetry predicts bilateral speech intelligibility but not listening effort in adults with bilateral cochlear implants. Front Neurosci 2022; 16:1038856. [PMID: 36570844 PMCID: PMC9768552 DOI: 10.3389/fnins.2022.1038856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
Introduction Bilateral cochlear implants (BiCIs) can facilitate improved speech intelligibility in noise and sound localization abilities compared to a unilateral implant in individuals with bilateral severe to profound hearing loss. Still, many individuals with BiCIs do not benefit from binaural hearing to the same extent that normal hearing (NH) listeners do. For example, binaural redundancy, a speech intelligibility benefit derived from having access to duplicate copies of a signal, is highly variable among BiCI users. Additionally, patients with hearing loss commonly report elevated listening effort compared to NH listeners. There is some evidence to suggest that BiCIs may reduce listening effort compared to a unilateral CI, but the limited existing literature has not shown this consistently. Critically, no studies to date have investigated this question using pupillometry to quantify listening effort, where large pupil sizes indicate high effort and small pupil sizes indicate low effort. Thus, the present study aimed to build on existing literature by investigating the potential benefits of BiCIs for both speech intelligibility and listening effort. Methods Twelve BiCI adults were tested in three listening conditions: Better Ear, Poorer Ear, and Bilateral. Stimuli were IEEE sentences presented from a loudspeaker at 0° azimuth in quiet. Participants were asked to repeat back the sentences, and responses were scored by an experimenter while changes in pupil dilation were measured. Results On average, participants demonstrated similar speech intelligibility in the Better Ear and Bilateral conditions, and significantly worse speech intelligibility in the Poorer Ear condition. Despite similar speech intelligibility in the Better Ear and Bilateral conditions, pupil dilation was significantly larger in the Bilateral condition. Discussion These results suggest that the BiCI users tested in this study did not demonstrate binaural redundancy in quiet. The large interaural speech asymmetries demonstrated by participants may have precluded them from obtaining binaural redundancy, as shown by the inverse relationship between the two variables. Further, participants did not obtain a release from effort when listening with two ears versus their better ear only. Instead, results indicate that bilateral listening elicited increased effort compared to better ear listening, which may be due to poor integration of asymmetric inputs.
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Affiliation(s)
- Emily A. Burg
- Waisman Center, University of Wisconsin-Madison, Madison, WI, United States,Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI, United States,*Correspondence: Emily A. Burg,
| | - Tanvi D. Thakkar
- Department of Psychology, University of Wisconsin-La Crosse, La Crosse, WI, United States
| | - Ruth Y. Litovsky
- Waisman Center, University of Wisconsin-Madison, Madison, WI, United States,Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI, United States,Division of Otolaryngology, Department of Surgery, University of Wisconsin-Madison, Madison, WI, United States
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Iwasaki S. Advances in auditory implants. Auris Nasus Larynx 2022; 50:321-326. [PMID: 36114071 DOI: 10.1016/j.anl.2022.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/21/2022] [Accepted: 09/01/2022] [Indexed: 11/30/2022]
Abstract
Auditory implants are classified into bone conduction (BAHA and Bonebridge; BB) and active middle ear implants (Vibrant Soundbridge; VSB) that stimulate cochlear hair cells, and cochlear implants (CIs) that stimulate neural structures. CIs should be performed as early as possible, and bilateral CIs have become popular because sound localization and speech recognition can be improved. CI is also considered a desirable treatment option for patients with single-sided deafness. VSB provides a safe and effective option for patients with conductive or mixed hearing loss and moderate to severe sensorineural hearing loss (SNHL); however, it use in patients with conductive or mixed hearing loss have only been approved in Japan. BAHA and BB implants have been approved by national insurance in Japan as bone conduction implants for patients with conductive or mixed hearing loss. Two fully implantable devices (Cochlear Carina and Envoy Esteem) are provided for patients with SNHL.
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Affiliation(s)
- Satoshi Iwasaki
- Department of Otorhinolaryngology, International University of Health and Welfare Mita Hospital, 1-4-3, Mita, Minato-ku, Tokyo 108-8329, Japan.
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Gaveau V, Coudert A, Salemme R, Koun E, Desoche C, Truy E, Farnè A, Pavani F. Benefits of active listening during 3D sound localization. Exp Brain Res 2022; 240:2817-2833. [PMID: 36071210 PMCID: PMC9587935 DOI: 10.1007/s00221-022-06456-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 08/28/2022] [Indexed: 11/29/2022]
Abstract
In everyday life, sound localization entails more than just the extraction and processing of auditory cues. When determining sound position in three dimensions, the brain also considers the available visual information (e.g., visual cues to sound position) and resolves perceptual ambiguities through active listening behavior (e.g., spontaneous head movements while listening). Here, we examined to what extent spontaneous head movements improve sound localization in 3D—azimuth, elevation, and depth—by comparing static vs. active listening postures. To this aim, we developed a novel approach to sound localization based on sounds delivered in the environment, brought into alignment thanks to a VR system. Our system proved effective for the delivery of sounds at predetermined and repeatable positions in 3D space, without imposing a physically constrained posture, and with minimal training. In addition, it allowed measuring participant behavior (hand, head and eye position) in real time. We report that active listening improved 3D sound localization, primarily by ameliorating accuracy and variability of responses in azimuth and elevation. The more participants made spontaneous head movements, the better was their 3D sound localization performance. Thus, we provide proof of concept of a novel approach to the study of spatial hearing, with potentials for clinical and industrial applications.
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Affiliation(s)
- V Gaveau
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France. .,University of Lyon 1, Lyon, France.
| | - A Coudert
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,ENT Departments, Hôpital Femme-Mère-Enfant and Edouard Herriot University Hospitals, Lyon, France
| | - R Salemme
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,Neuro-immersion, Lyon, France
| | - E Koun
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France
| | - C Desoche
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,Neuro-immersion, Lyon, France
| | - E Truy
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,ENT Departments, Hôpital Femme-Mère-Enfant and Edouard Herriot University Hospitals, Lyon, France
| | - A Farnè
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,Neuro-immersion, Lyon, France
| | - F Pavani
- Integrative Multisensory Perception Action & Cognition Team-ImpAct, Lyon Neuroscience Research Center, INSERM U1028, CNRS U5292, 16 Av. Doyen Lépine, BRON cedex, 69500, Lyon, France.,University of Lyon 1, Lyon, France.,Center for Mind/Brain Sciences - CIMeC, University of Trento, Rovereto, Italy
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14
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Gibbs BE, Bernstein JGW, Brungart DS, Goupell MJ. Effects of better-ear glimpsing, binaural unmasking, and spectral resolution on spatial release from masking in cochlear-implant users. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 152:1230. [PMID: 36050186 PMCID: PMC9420049 DOI: 10.1121/10.0013746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 06/15/2023]
Abstract
Bilateral cochlear-implant (BICI) listeners obtain less spatial release from masking (SRM; speech-recognition improvement for spatially separated vs co-located conditions) than normal-hearing (NH) listeners, especially for symmetrically placed maskers that produce similar long-term target-to-masker ratios at the two ears. Two experiments examined possible causes of this deficit, including limited better-ear glimpsing (using speech information from the more advantageous ear in each time-frequency unit), limited binaural unmasking (using interaural differences to improve signal-in-noise detection), or limited spectral resolution. Listeners had NH (presented with unprocessed or vocoded stimuli) or BICIs. Experiment 1 compared natural symmetric maskers, idealized monaural better-ear masker (IMBM) stimuli that automatically performed better-ear glimpsing, and hybrid stimuli that added worse-ear information, potentially restoring binaural cues. BICI and NH-vocoded SRM was comparable to NH-unprocessed SRM for idealized stimuli but was 14%-22% lower for symmetric stimuli, suggesting limited better-ear glimpsing ability. Hybrid stimuli improved SRM for NH-unprocessed listeners but degraded SRM for BICI and NH-vocoded listeners, suggesting they experienced across-ear interference instead of binaural unmasking. In experiment 2, increasing the number of vocoder channels did not change NH-vocoded SRM. BICI SRM deficits likely reflect a combination of across-ear interference, limited better-ear glimpsing, and poorer binaural unmasking that stems from cochlear-implant-processing limitations other than reduced spectral resolution.
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Affiliation(s)
- Bobby E Gibbs
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Joshua G W Bernstein
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland 20889, USA
| | - Douglas S Brungart
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland 20889, USA
| | - Matthew J Goupell
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
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15
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Computed-Tomography Estimates of Interaural Mismatch in Insertion Depth and Scalar Location in Bilateral Cochlear-Implant Users. Otol Neurotol 2022; 43:666-675. [PMID: 35761459 DOI: 10.1097/mao.0000000000003538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
HYPOTHESIS Bilateral cochlear-implant (BI-CI) users will have a range of interaural insertion-depth mismatch because of different array placement or characteristics. Mismatch will be larger for electrodes located near the apex or outside scala tympani, or for arrays that are a mix of precurved and straight types. BACKGROUND Brainstem superior olivary-complex neurons are exquisitely sensitive to interaural-difference cues for sound localization. Because these neurons rely on interaurally place-of-stimulation-matched inputs, interaural insertion-depth or scalar-location differences for BI-CI users could cause interaural place-of-stimulation mismatch that impairs binaural abilities. METHODS Insertion depths and scalar locations were calculated from temporal-bone computed-tomography scans for 107 BI-CI users (27 Advanced Bionics, 62 Cochlear, 18 MED-EL). RESULTS Median interaural insertion-depth mismatch was 23.4 degrees or 1.3 mm. Mismatch in the estimated clinically relevant range expected to impair binaural processing (>75 degrees or 3 mm) occurred for 13 to 19% of electrode pairs overall, and for at least three electrode pairs for 23 to 37% of subjects. There was a significant three-way interaction between insertion depth, scalar location, and array type. Interaural insertion-depth mismatch was largest for apical electrodes, for electrode pairs in two different scala, and for arrays that were both-precurved. CONCLUSION Average BI-CI interaural insertion-depth mismatch was small; however, large interaural insertion-depth mismatch-with the potential to degrade spatial hearing-occurred frequently enough to warrant attention. For new BICI users, improved surgical techniques to avoid interaural insertion-depth and scalar mismatch are recommended. For existing BI-CI users with interaural insertion-depth mismatch, interaural alignment of clinical frequency tables might reduce negative spatial-hearing consequences.
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16
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Holder JT, Holcomb MA, Snapp H, Labadie RF, Vroegop J, Rocca C, Elgandy MS, Dunn C, Gifford RH. Guidelines for Best Practice in the Audiological Management of Adults Using Bimodal Hearing Configurations. OTOLOGY & NEUROTOLOGY OPEN 2022; 2:e011. [PMID: 36274668 PMCID: PMC9581116 DOI: 10.1097/ono.0000000000000011] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Clinics are treating a growing number of patients with greater amounts of residual hearing. These patients often benefit from a bimodal hearing configuration in which acoustic input from a hearing aid on 1 ear is combined with electrical stimulation from a cochlear implant on the other ear. The current guidelines aim to review the literature and provide best practice recommendations for the evaluation and treatment of individuals with bilateral sensorineural hearing loss who may benefit from bimodal hearing configurations. Specifically, the guidelines review: benefits of bimodal listening, preoperative and postoperative cochlear implant evaluation and programming, bimodal hearing aid fitting, contralateral routing of signal considerations, bimodal treatment for tinnitus, and aural rehabilitation recommendations.
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Affiliation(s)
| | | | | | | | | | - Christine Rocca
- Guy’s and St. Thomas’ Hearing Implant Centre, London, United Kingdom
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17
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Smeal M, Snapp H, Ausili S, Holcomb M, Prentiss S. Effects of Bilateral Cochlear Implantation on Binaural Listening Tasks for Younger and Older Adults. Audiol Neurootol 2022; 27:377-387. [PMID: 35636400 DOI: 10.1159/000523914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 02/24/2022] [Indexed: 11/19/2022] Open
Abstract
PURPOSE This study investigated the objective and subjective benefit of a second cochlear implant (CI) on binaural listening tasks of speech understanding in noise and localization in younger and older adults. We aimed to determine if the aging population can utilize binaural cues and obtain comparable benefits from bilateral CI (BIL_CI) when compared to the younger population. METHODS Twenty-nine adults with severe to profound bilateral sensorineural hearing loss were included. Participants were evaluated in two conditions, better CI (BE_CI) alone and BIL_CI using AzBio and Bamford-Kowal-Bench (BKB) sentence in noise tests. Localization tasks were completed in the BIL_CI condition using a broadband stimulus, low-frequency stimuli, and high-frequency stimuli. A subjective questionnaire was administered to assess satisfaction with CI. RESULTS Older age was significantly associated with poorer performance on AzBio +5 dB signal-to-noise ratio (SNR) and BKB-speech in noise (SIN); however, improvements from BE_CI to BIL_CI were observed across all ages. In the AzBio +5 condition, nearly half of all participants achieved a significant improvement from BE_CI to BIL_CI with the majority of those occurring in patients younger than 65 years of age. Conversely, the majority of participants who achieved a significant improvement in BKB-SIN were adults >65 years of age. Years of BIL_CI experience and time between implants were not associated with performance. For localization, mean absolute error increased with age for low and high narrowband noise, but not for the broadband noise. Response gain was negatively correlated with age for all localization stimuli. Neither BIL_CI listening experience nor time between implants significantly impacted localization ability. Subjectively, participants report reduction in disability with the addition of the second CI. There is no observed relationship between age or speech recognition score and satisfaction with BIL_CI. CONCLUSION Overall performance on binaural listening tasks was poorer in older adults than in younger adults. However, older adults were able to achieve significant benefit from the addition of a second CI, and performance on binaural tasks was not correlated with overall device satisfaction. The significance of the improvement was task and stimulus dependent but suggested a critical limit may exist for optimal performance on SIN tasks for CI users. Specifically, older adults require at least a +8 dB SNR to understand 50% of speech postoperatively; therefore, solely utilizing a fixed +5 dB SNR preoperatively to qualify CI candidates is not recommended as this test condition may introduce limitations in demonstrating CI benefit.
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Affiliation(s)
- Molly Smeal
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
| | - Hillary Snapp
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
| | - Sebastian Ausili
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
| | - Meredith Holcomb
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
| | - Sandra Prentiss
- Department of Otolaryngology, University of Miami, Miami, Florida, USA
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18
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Valzolgher C, Todeschini M, Verdelet G, Gatel J, Salemme R, Gaveau V, Truy E, Farnè A, Pavani F. Adapting to altered auditory cues: Generalization from manual reaching to head pointing. PLoS One 2022; 17:e0263509. [PMID: 35421095 PMCID: PMC9009652 DOI: 10.1371/journal.pone.0263509] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 01/21/2022] [Indexed: 12/02/2022] Open
Abstract
Localising sounds means having the ability to process auditory cues deriving from the interplay among sound waves, the head and the ears. When auditory cues change because of temporary or permanent hearing loss, sound localization becomes difficult and uncertain. The brain can adapt to altered auditory cues throughout life and multisensory training can promote the relearning of spatial hearing skills. Here, we study the training potentials of sound-oriented motor behaviour to test if a training based on manual actions toward sounds can learning effects that generalize to different auditory spatial tasks. We assessed spatial hearing relearning in normal hearing adults with a plugged ear by using visual virtual reality and body motion tracking. Participants performed two auditory tasks that entail explicit and implicit processing of sound position (head-pointing sound localization and audio-visual attention cueing, respectively), before and after having received a spatial training session in which they identified sound position by reaching to auditory sources nearby. Using a crossover design, the effects of the above-mentioned spatial training were compared to a control condition involving the same physical stimuli, but different task demands (i.e., a non-spatial discrimination of amplitude modulations in the sound). According to our findings, spatial hearing in one-ear plugged participants improved more after reaching to sound trainings rather than in the control condition. Training by reaching also modified head-movement behaviour during listening. Crucially, the improvements observed during training generalize also to a different sound localization task, possibly as a consequence of acquired and novel head-movement strategies.
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Affiliation(s)
- Chiara Valzolgher
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- Center for Mind/Brain Sciences—CIMeC, University of Trento, Trento, Italy
- * E-mail:
| | - Michela Todeschini
- Department of Psychology and Cognitive Sciences (DiPSCo), University of Trento, Trento, Italy
| | - Gregoire Verdelet
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- Neuroimmersion, Lyon Neuroscience Research Center, Lyon, France
| | | | - Romeo Salemme
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- Neuroimmersion, Lyon Neuroscience Research Center, Lyon, France
| | - Valerie Gaveau
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- University of Lyon 1, Villeurbanne, France
| | - Eric Truy
- Hospices Civils de Lyon, Lyon, France
| | - Alessandro Farnè
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- Center for Mind/Brain Sciences—CIMeC, University of Trento, Trento, Italy
- Neuroimmersion, Lyon Neuroscience Research Center, Lyon, France
| | - Francesco Pavani
- Integrative, Multisensory, Perception, Action and Cognition Team (IMPACT), Lyon Neuroscience Research Center, Lyon, France
- Center for Mind/Brain Sciences—CIMeC, University of Trento, Trento, Italy
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19
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Moore BCJ. Listening to Music Through Hearing Aids: Potential Lessons for Cochlear Implants. Trends Hear 2022; 26:23312165211072969. [PMID: 35179052 PMCID: PMC8859663 DOI: 10.1177/23312165211072969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Some of the problems experienced by users of hearing aids (HAs) when listening to music are relevant to cochlear implants (CIs). One problem is related to the high peak levels (up to 120 dB SPL) that occur in live music. Some HAs and CIs overload at such levels, because of the limited dynamic range of the microphones and analogue-to-digital converters (ADCs), leading to perceived distortion. Potential solutions are to use 24-bit ADCs or to include an adjustable gain between the microphones and the ADCs. A related problem is how to squeeze the wide dynamic range of music into the limited dynamic range of the user, which can be only 6-20 dB for CI users. In HAs, this is usually done via multi-channel amplitude compression (automatic gain control, AGC). In CIs, a single-channel front-end AGC is applied to the broadband input signal or a control signal derived from a running average of the broadband signal level is used to control the mapping of the channel envelope magnitude to an electrical signal. This introduces several problems: (1) an intense narrowband signal (e.g. a strong bass sound) reduces the level for all frequency components, making some parts of the music harder to hear; (2) the AGC introduces cross-modulation effects that can make a steady sound (e.g. sustained strings or a sung note) appear to fluctuate in level. Potential solutions are to use several frequency channels to create slowly varying gain-control signals and to use slow-acting (or dual time-constant) AGC rather than fast-acting AGC.
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Affiliation(s)
- Brian C J Moore
- Cambridge Hearing Group, Department of Psychology, 2152University of Cambridge, Cambridge, England
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20
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Pitch Accuracy of Vocal Singing in Deaf Children With Bimodal Hearing and Bilateral Cochlear Implants. Ear Hear 2022; 43:1336-1346. [PMID: 34923555 PMCID: PMC9198103 DOI: 10.1097/aud.0000000000001189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The purpose of the present study was to investigate the pitch accuracy of vocal singing in children with severe to profound hearing loss who use bilateral cochlear implants (CIs) or bimodal devices [CI at one ear and hearing aid (HA) at the other] in comparison to similarly-aged children with normal-hearing (NH). DESIGN The participants included four groups: (1) 26 children with NH, (2) 13 children with bimodal devices, (3) 31 children with bilateral CIs that were implanted sequentially, and (4) 10 children with bilateral CIs that were implanted simultaneously. All participants were aged between 7 and 11 years old. Each participant was recorded singing a self-chosen song that was familiar to him or her. The fundamental frequencies (F0) of individual sung notes were extracted and normalized to facilitate cross-subject comparisons. Pitch accuracy was quantified using four pitch-based metrics calculated with reference to the target music notes: mean note deviation, contour direction, mean interval deviation, and F0 variance ratio. A one-way ANOVA was used to compare listener-group difference on each pitch metric. A principal component analysis showed that the mean note deviation best accounted for pitch accuracy in vocal singing. A regression analysis examined potential predictors of CI children's singing proficiency using mean note deviation as the dependent variable and demographic and audiological factors as independent variables. RESULTS The results revealed significantly poorer performance on all four pitch-based metrics in the three groups of children with CIs in comparison to children with NH. No significant differences were found among the three CI groups. Among the children with CIs, variability in the vocal singing proficiency was large. Within the group of 13 bimodal users, the mean note deviation was significantly correlated with their unaided pure-tone average thresholds (r = 0.582, p = 0.037). The regression analysis for all children with CIs, however, revealed no significant demographic or audiological predictor for their vocal singing performance. CONCLUSION Vocal singing performance in children with bilateral CIs or bimodal devices is not significantly different from each other on a group level. Compared to children with NH, the pediatric bimodal and bilateral CI users, in general, demonstrated significant deficits in vocal singing ability. Demographic and audiological factors, known from previous studies to be associated with good speech and language development in prelingually-deafened children with CIs, were not associated with singing accuracy for these children.
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21
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Pinheiro MMC, Mancini PC, Soares AD, Ribas Â, Lima DP, Cavadas M, Banhara MR, Carvalho SADS, Buzo BC. Comparison of Speech Recognition in Cochlear Implant Users with Different Speech Processors. J Am Acad Audiol 2021; 32:469-476. [PMID: 34847587 DOI: 10.1055/s-0041-1735252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Speech recognition in noisy environments is a challenge for both cochlear implant (CI) users and device manufacturers. CI manufacturers have been investing in technological innovations for processors and researching strategies to improve signal processing and signal design for better aesthetic acceptance and everyday use. PURPOSE This study aimed to compare speech recognition in CI users using off-the-ear (OTE) and behind-the-ear (BTE) processors. DESIGN A cross-sectional study was conducted with 51 CI recipients, all users of the BTE Nucleus 5 (CP810) sound processor. Speech perception performances were compared in quiet and noisy conditions using the BTE sound processor Nucleus 5 (N5) and OTE sound processor Kanso. Each participant was tested with the Brazilian-Portuguese version of the hearing in noise test using each sound processor in a randomized order. Three test conditions were analyzed with both sound processors: (i) speech level fixed at 65 decibel sound pressure level in a quiet, (ii) speech and noise at fixed levels, and (iii) adaptive speech levels with a fixed noise level. To determine the relative performance of OTE with respect to BTE, paired comparison analyses were performed. RESULTS The paired t-tests showed no significant difference between the N5 and Kanso in quiet conditions. In all noise conditions, the performance of the OTE (Kanso) sound processor was superior to that of the BTE (N5), regardless of the order in which they were used. With the speech and noise at fixed levels, a significant mean 8.1 percentage point difference was seen between Kanso (78.10%) and N5 (70.7%) in the sentence scores. CONCLUSION CI users had a lower signal-to-noise ratio and a higher percentage of sentence recognition with the OTE processor than with the BTE processor.
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Affiliation(s)
| | - Patricia Cotta Mancini
- Department of Speech-Language Pathology and Audiology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Alexandra Dezani Soares
- Centro do Deficiente Auditivo - Hospital São Paulo, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ângela Ribas
- Centro de Implante Coclear do Hospital Pequeno Príncipe, Curitiba, Paraná, Brazil
| | - Danielle Penna Lima
- Centro de Implantes Cocleares do Hospital do Coração de Natal, Natal, Brazil
| | - Marcia Cavadas
- Department of Speech-Language Pathology and Audiology, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Equipe Sonora, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcos Roberto Banhara
- Centro Especializado de Reabilitação IV do Hospital Santo Antônio/Obras Sociais Irmã Dulce, Salvador, Bahia, Brazil
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22
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Kim GH, Aronoff JM. Using unilateral stimulation to create a reference for bilateral fusion judgments. JASA EXPRESS LETTERS 2021; 1:114401. [PMID: 34778874 PMCID: PMC8565497 DOI: 10.1121/10.0007058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Measuring binaural fusion can be challenging, especially with bilateral cochlear implant (CI) users. This study validated a technique of using unilateral stimulation to create a reference for measuring fusion. Seven bilateral CI users listened to stimuli randomly presented to the right, left, or both ears. Participants indicated the size, number, and location of the resulting image(s) they perceived. The participants had largely unitary, punctate percepts that were lateralized to the stimulated ear for unilateral stimuli. The image was centered but more diffuse when the stimuli were presented bilaterally. The results suggest unilateral stimuli can provide a reference for binaural fusion.
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Affiliation(s)
- Grace Hyerin Kim
- Speech and Hearing Science Department, University of Illinois at Urbana-Champaign, 901 S. 6thStreet, Champaign, Illinois 61801, USA ,
| | - Justin M Aronoff
- Speech and Hearing Science Department, University of Illinois at Urbana-Champaign, 901 S. 6thStreet, Champaign, Illinois 61801, USA ,
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23
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Fischer T, Schmid C, Kompis M, Mantokoudis G, Caversaccio M, Wimmer W. Effects of temporal fine structure preservation on spatial hearing in bilateral cochlear implant users. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:673. [PMID: 34470279 DOI: 10.1121/10.0005732] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Typically, the coding strategies of cochlear implant audio processors discard acoustic temporal fine structure information (TFS), which may be related to the poor perception of interaural time differences (ITDs) and the resulting reduced spatial hearing capabilities compared to normal-hearing individuals. This study aimed to investigate to what extent bilateral cochlear implant (BiCI) recipients can exploit ITD cues provided by a TFS preserving coding strategy (FS4) in a series of sound field spatial hearing tests. As a baseline, we assessed the sensitivity to ITDs and binaural beats of 12 BiCI subjects with a coding strategy disregarding fine structure (HDCIS) and the FS4 strategy. For 250 Hz pure-tone stimuli but not for broadband noise, the BiCI users had significantly improved ITD discrimination using the FS4 strategy. In the binaural beat detection task and the broadband sound localization, spatial discrimination, and tracking tasks, no significant differences between the two tested coding strategies were observed. These results suggest that ITD sensitivity did not generalize to broadband stimuli or sound field spatial hearing tests, suggesting that it would not be useful for real-world listening.
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Affiliation(s)
- T Fischer
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
| | - C Schmid
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
| | - M Kompis
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
| | - G Mantokoudis
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
| | - M Caversaccio
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
| | - W Wimmer
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010 Bern, Switzerland
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24
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Gajecki T, Nogueira W. Enhancement of interaural level differences for bilateral cochlear implant users. Hear Res 2021; 409:108313. [PMID: 34340023 DOI: 10.1016/j.heares.2021.108313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 05/19/2021] [Accepted: 07/12/2021] [Indexed: 11/15/2022]
Abstract
Bilateral cochlear implant (BiCI) users do not localize sounds as well as normal hearing (NH) listeners do. NH listeners rely on two binaural cues to localize sounds in the horizontal plane, namely interaural level differences (ILDs) and interaural time differences. BiCI systems, however, convey these cues poorly. In this work, we investigated two methods to improve the coding of ILDs in BiCIs. The first method enhances ILDs by applying an artificial current-versus-angle function to the clinical levels delivered by the basal electrodes of the CI contralateral to the target sound. The second method enhances ILDs by using bilaterally linked N-of-M band selection. Results indicate that the participants were able to discriminate the location of the sound more accurately at narrow azimuths when the ILD enhancement was applied, compared to when they were using natural ILDs. Also, the results show that linking the band selection had a positive effect on left/right discrimination accuracy at larger azimuths for three out of the 10 tested participants, when compared to unlinked band selection. Based on these results, we conclude that ILD enhancement besides linked N-of-M band selection can help some BiCI participants to discriminate sound sources on the frontal horizontal plane.
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Affiliation(s)
- Tom Gajecki
- Department of Otolaryngology, Medical University Hannover and Cluster of Excellence Hearing4all, Hannover, 30625, Germany.
| | - Waldo Nogueira
- Department of Otolaryngology, Medical University Hannover and Cluster of Excellence Hearing4all, Hannover, 30625, Germany.
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Sheffield SW, Goupell MJ, Spencer NJ, Stakhovskaya OA, Bernstein JGW. Binaural Optimization of Cochlear Implants: Discarding Frequency Content Without Sacrificing Head-Shadow Benefit. Ear Hear 2021; 41:576-590. [PMID: 31436754 PMCID: PMC7028504 DOI: 10.1097/aud.0000000000000784] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Single-sided deafness cochlear-implant (SSD-CI) listeners and bilateral cochlear-implant (BI-CI) listeners gain near-normal levels of head-shadow benefit but limited binaural benefits. One possible reason for these limited binaural benefits is that cochlear places of stimulation tend to be mismatched between the ears. SSD-CI and BI-CI patients might benefit from a binaural fitting that reallocates frequencies to reduce interaural place mismatch. However, this approach could reduce monaural speech recognition and head-shadow benefit by excluding low- or high-frequency information from one ear. This study examined how much frequency information can be excluded from a CI signal in the poorer-hearing ear without reducing head-shadow benefits and how these outcomes are influenced by interaural asymmetry in monaural speech recognition. DESIGN Speech-recognition thresholds for sentences in speech-shaped noise were measured for 6 adult SSD-CI listeners, 12 BI-CI listeners, and 9 normal-hearing listeners presented with vocoder simulations. Stimuli were presented using nonindividualized in-the-ear or behind-the-ear head-related impulse-response simulations with speech presented from a 70° azimuth (poorer-hearing side) and noise from 70° (better-hearing side), thereby yielding a better signal-to-noise ratio (SNR) at the poorer-hearing ear. Head-shadow benefit was computed as the improvement in bilateral speech-recognition thresholds gained from enabling the CI in the poorer-hearing, better-SNR ear. High- or low-pass filtering was systematically applied to the head-related impulse-response-filtered stimuli presented to the poorer-hearing ear. For the SSD-CI listeners and SSD-vocoder simulations, only high-pass filtering was applied, because the CI frequency allocation would never need to be adjusted downward to frequency-match the ears. For the BI-CI listeners and BI-vocoder simulations, both low and high pass filtering were applied. The normal-hearing listeners were tested with two levels of performance to examine the effect of interaural asymmetry in monaural speech recognition (vocoder synthesis-filter slopes: 5 or 20 dB/octave). RESULTS Mean head-shadow benefit was smaller for the SSD-CI listeners (~7 dB) than for the BI-CI listeners (~14 dB). For SSD-CI listeners, frequencies <1236 Hz could be excluded; for BI-CI listeners, frequencies <886 or >3814 Hz could be excluded from the poorer-hearing ear without reducing head-shadow benefit. Bilateral performance showed greater immunity to filtering than monaural performance, with gradual changes in performance as a function of filter cutoff. Real and vocoder-simulated CI users with larger interaural asymmetry in monaural performance had less head-shadow benefit. CONCLUSIONS The "exclusion frequency" ranges that could be removed without diminishing head-shadow benefit are interpreted in terms of low importance in the speech intelligibility index and a small head-shadow magnitude at low frequencies. Although groups and individuals with greater performance asymmetry gained less head-shadow benefit, the magnitudes of these factors did not predict the exclusion frequency range. Overall, these data suggest that for many SSD-CI and BI-CI listeners, the frequency allocation for the poorer-ear CI can be shifted substantially without sacrificing head-shadow benefit, at least for energetic maskers. Considering the two ears together as a single system may allow greater flexibility in discarding redundant frequency content from a CI in one ear when considering bilateral programming solutions aimed at reducing interaural frequency mismatch.
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Affiliation(s)
- Sterling W. Sheffield
- Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, FL, USA
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD USA
| | - Matthew J. Goupell
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD, USA
| | | | - Olga A. Stakhovskaya
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD USA
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD, USA
| | - Joshua G. W. Bernstein
- National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD USA
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26
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Fletcher MD, Verschuur CA. Electro-Haptic Stimulation: A New Approach for Improving Cochlear-Implant Listening. Front Neurosci 2021; 15:581414. [PMID: 34177440 PMCID: PMC8219940 DOI: 10.3389/fnins.2021.581414] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 04/29/2021] [Indexed: 12/12/2022] Open
Abstract
Cochlear implants (CIs) have been remarkably successful at restoring speech perception for severely to profoundly deaf individuals. Despite their success, several limitations remain, particularly in CI users' ability to understand speech in noisy environments, locate sound sources, and enjoy music. A new multimodal approach has been proposed that uses haptic stimulation to provide sound information that is poorly transmitted by the implant. This augmenting of the electrical CI signal with haptic stimulation (electro-haptic stimulation; EHS) has been shown to improve speech-in-noise performance and sound localization in CI users. There is also evidence that it could enhance music perception. We review the evidence of EHS enhancement of CI listening and discuss key areas where further research is required. These include understanding the neural basis of EHS enhancement, understanding the effectiveness of EHS across different clinical populations, and the optimization of signal-processing strategies. We also discuss the significant potential for a new generation of haptic neuroprosthetic devices to aid those who cannot access hearing-assistive technology, either because of biomedical or healthcare-access issues. While significant further research and development is required, we conclude that EHS represents a promising new approach that could, in the near future, offer a non-invasive, inexpensive means of substantially improving clinical outcomes for hearing-impaired individuals.
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Affiliation(s)
- Mark D. Fletcher
- Faculty of Engineering and Physical Sciences, University of Southampton Auditory Implant Service, University of Southampton, Southampton, United Kingdom
- Faculty of Engineering and Physical Sciences, Institute of Sound and Vibration Research, University of Southampton, Southampton, United Kingdom
| | - Carl A. Verschuur
- Faculty of Engineering and Physical Sciences, University of Southampton Auditory Implant Service, University of Southampton, Southampton, United Kingdom
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Improvements in Hearing and in Quality of Life after Sequential Bilateral Cochlear Implantation in a Consecutive Sample of Adult Patients with Severe-to-Profound Hearing Loss. J Clin Med 2021; 10:jcm10112394. [PMID: 34071662 PMCID: PMC8199295 DOI: 10.3390/jcm10112394] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/21/2021] [Accepted: 05/26/2021] [Indexed: 11/16/2022] Open
Abstract
Bilateral cochlear implantation is increasing worldwide. In adults, bilateral cochlear implants (BICI) are often performed sequentially with a time delay between the first (CI1) and the second (CI2) implant. The benefits of BICI have been reported for well over a decade. This study aimed at investigating these benefits for a consecutive sample of adult patients. Improvements in speech-in-noise recognition after CI2 were followed up longitudinally for 12 months with the internationally comparable Finnish matrix sentence test. The test scores were statistically significantly better for BICI than for either CI alone in all assessments during the 12-month period. At the end of the follow-up period, the bilateral benefit for co-located speech and noise was 1.4 dB over CI1 and 1.7 dB over CI2, and when the noise was moved from the front to 90 degrees on the side, spatial release from masking amounted to an improvement of 2.5 dB in signal-to-noise ratio. To assess subjective improvements in hearing and in quality of life, two questionnaires were used. Both questionnaires revealed statistically significant improvements due to CI2 and BICI. The association between speech recognition in noise and background factors (duration of hearing loss/deafness, time between implants) or subjective improvements was markedly smaller than what has been previously reported on sequential BICI in adults. Despite the relatively heterogeneous sample, BICI improved hearing and quality of life.
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Burg EA, Thakkar T, Fields T, Misurelli SM, Kuchinsky SE, Roche J, Lee DJ, Litovsky RY. Systematic Comparison of Trial Exclusion Criteria for Pupillometry Data Analysis in Individuals With Single-Sided Deafness and Normal Hearing. Trends Hear 2021; 25:23312165211013256. [PMID: 34024219 PMCID: PMC8150669 DOI: 10.1177/23312165211013256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The measurement of pupil dilation has become a common way to assess listening effort. Pupillometry data are subject to artifacts, requiring highly contaminated data to be discarded from analysis. It is unknown how trial exclusion criteria impact experimental results. The present study examined the effect of a common exclusion criterion, percentage of blinks, on speech intelligibility and pupil dilation measures in 9 participants with single-sided deafness (SSD) and 20 participants with normal hearing. Participants listened to and repeated sentences in quiet or with speech maskers. Pupillometry trials were processed using three levels of blink exclusion criteria: 15%, 30%, and 45%. These percentages reflect a threshold for missing data points in a trial, where trials that exceed the threshold are excluded from analysis. Results indicated that pupil dilation was significantly greater and intelligibility was significantly lower in the masker compared with the quiet condition for both groups. Across-group comparisons revealed that speech intelligibility in the SSD group decreased significantly more than the normal hearing group from quiet to masker conditions, but the change in pupil dilation was similar for both groups. There was no effect of blink criteria on speech intelligibility or pupil dilation results for either group. However, the total percentage of blinks in the masker condition was significantly greater than in the quiet condition for the SSD group, which is consistent with previous studies that have found a relationship between blinking and task difficulty. This association should be carefully considered in future experiments using pupillometry to gauge listening effort.
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Affiliation(s)
- Emily A Burg
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Tanvi Thakkar
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Taylor Fields
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Sara M Misurelli
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, School of Medicine & Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Stefanie E Kuchinsky
- Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland, United States
| | - Joseph Roche
- Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, School of Medicine & Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Daniel J Lee
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States
| | - Ruth Y Litovsky
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, School of Medicine & Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States
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29
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Dwyer RT, Chen C, Hehrmann P, Dwyer NC, Gifford RH. Synchronized Automatic Gain Control in Bilateral Cochlear Implant Recipients Yields Significant Benefit in Static and Dynamic Listening Conditions. Trends Hear 2021; 25:23312165211014139. [PMID: 34027718 PMCID: PMC8150445 DOI: 10.1177/23312165211014139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 03/26/2021] [Accepted: 04/01/2021] [Indexed: 11/30/2022] Open
Abstract
Individuals with bilateral cochlear implants (BiCIs) rely mostly on interaural level difference (ILD) cues to localize stationary sounds in the horizontal plane. Independent automatic gain control (AGC) in each device can distort this cue, resulting in poorer localization of stationary sound sources. However, little is known about how BiCI listeners perceive sound in motion. In this study, 12 BiCI listeners' spatial hearing abilities were assessed for both static and dynamic listening conditions when the sound processors were synchronized by applying the same compression gain to both devices as a means to better preserve the original ILD cues. Stimuli consisted of band-pass filtered (100-8000 Hz) Gaussian noise presented at various locations or panned over an array of loudspeakers. In the static listening condition, the distance between two sequentially presented stimuli was adaptively varied to arrive at the minimum audible angle, the smallest spatial separation at which the listener can correctly determine whether the second sound was to the left or right of the first. In the dynamic listening condition, participants identified if a single stimulus moved to the left or to the right. Velocity was held constant and the distance the stimulus traveled was adjusted using an adaptive procedure to determine the minimum audible movement angle. Median minimum audible angle decreased from 17.1° to 15.3° with the AGC synchronized. Median minimum audible movement angle decreased from 100° to 25.5°. These findings were statistically significant and support the hypothesis that synchronizing the AGC better preserves ILD cues and results in improved spatial hearing abilities. However, restoration of the ILD cue alone was not enough to bridge the large performance gap between BiCI listeners and normal-hearing listeners on these static and dynamic spatial hearing measures.
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Affiliation(s)
- Robert T. Dwyer
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - Chen Chen
- Research and Technology, Advanced Bionics, LLC, Valencia, California, United States
| | - Phillipp Hehrmann
- Research and Technology, Advanced Bionics, LLC, Valencia, California, United States
| | - Nichole C. Dwyer
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - René H. Gifford
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, Tennessee, United States
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30
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Chauhan I, Swami H, Natraj R. A study on relationship between Neural Response Telemetry and behavioural Threshold/Comfort levels in children with cochlear implant. Med J Armed Forces India 2020; 77:224-229. [PMID: 33867642 DOI: 10.1016/j.mjafi.2020.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/12/2020] [Indexed: 11/17/2022] Open
Abstract
Background Our study was a prospective, non-randomised, single tertiary care centre study involving 50 children below 10 years, all implanted with Nucleus 24™ cochlear implants to find the relationship between intra-operative NRT (Neural Response Telemetry) values and post-operatively behaviourally obtained Threshold (T) and Comfort (C) levels. Methods NRT threshold values were obtained intra-operatively by using Custom Sound EP Software V 4.4™ (Cochlear Corporation). At switch-on after three weeks, behavioural T and C levels were measured based on behavioural responses given by patients using Custom Sound Version 4.4 software™ (Cochlear Corporation). NRT values were also measured at switch-on, 2 months, 3 months and 6 months. Results Intra-operative NRT levels (187.96 ± 12.48) were higher than both T (160.63 ± 22.69) and C (181.21 ± 22.41) levels obtained after 3 weeks. In addition, there was a weak correlation of NRT values with T (P value: 0.05, r = 0.391) and C (P value: 0.05, r = 0.390) levels. Conclusion NRT is a quick and non-invasive tool to confirm cochlear implant integrity. There is a weak correlation of NRT values with both T and C levels and therefore, intra-operative NRT is a weak predictor for setting both T and C levels at switch-on.
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Affiliation(s)
- Indrajeet Chauhan
- Graded Specialist (ENT), Military Hospital, Yol Cantt, Himachal Pradesh, India
| | - Himanshu Swami
- HoD & Senior Advisor (ENT), Army Hospital (R&R), Delhi Cantt, India
| | - Rashmi Natraj
- Clinical Audiologist & Speech Therapist, Command Hospital (Air Force), Bengaluru, India
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31
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Fletcher MD. Using haptic stimulation to enhance auditory perception in hearing-impaired listeners. Expert Rev Med Devices 2020; 18:63-74. [PMID: 33372550 DOI: 10.1080/17434440.2021.1863782] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Hearing-assistive devices, such as hearing aids and cochlear implants, transform the lives of hearing-impaired people. However, users often struggle to locate and segregate sounds. This leads to impaired threat detection and an inability to understand speech in noisy environments. Recent evidence suggests that segregation and localization can be improved by providing missing sound-information through haptic stimulation. AREAS COVERED This article reviews the evidence that haptic stimulation can effectively provide sound information. It then discusses the research and development required for this approach to be implemented in a clinically viable device. This includes discussion of what sound information should be provided and how that information can be extracted and delivered. EXPERT OPINION Although this research area has only recently emerged, it builds on a significant body of work showing that sound information can be effectively transferred through haptic stimulation. Current evidence suggests that haptic stimulation is highly effective at providing missing sound-information to cochlear implant users. However, a great deal of work remains to implement this approach in an effective wearable device. If successful, such a device could offer an inexpensive, noninvasive means of improving educational, work, and social experiences for hearing-impaired individuals, including those without access to hearing-assistive devices.
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Affiliation(s)
- Mark D Fletcher
- University of Southampton Auditory Implant Service, Southampton, UK.,Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
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32
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Kan A, Meng Q. The Temporal Limits Encoder as a Sound Coding Strategy for Bilateral Cochlear Implants. IEEE/ACM TRANSACTIONS ON AUDIO, SPEECH, AND LANGUAGE PROCESSING 2020; 29:265-273. [PMID: 33409339 PMCID: PMC7781292 DOI: 10.1109/taslp.2020.3039601] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The difference in binaural benefit between bilateral cochlear implant (CI) users and normal hearing (NH) listeners has typically been attributed to CI sound coding strategies not encoding the acoustic fine structure (FS) interaural time differences (ITD). The Temporal Limits Encoder (TLE) strategy is proposed as a potential way of improving binaural hearing benefits for CI users in noisy situations. TLE works by downward-transposition of mid-frequency band-limited channel information and can theoretically provide FS-ITD cues. In this work, the effect of choice of lower limit of the modulator in TLE was examined by measuring performance on a word recognition task and computing the magnitude of binaural benefit in bilateral CI users. Performance listening with the TLE strategy was compared with the commonly used Advanced Combinational Encoder (ACE) CI sound coding strategy. Results showed that setting the lower limit to ≥200 Hz maintained word recognition performance comparable to that of ACE. While most CI listeners exhibited a large binaural benefit (≥6 dB) in at least one of the conditions tested, there was no systematic relationship between the lower limit of the modulator and performance. These results indicate that the TLE strategy has potential to improve binaural hearing abilities in CI users but further work is needed to understand how binaural benefit can be maximized.
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Affiliation(s)
- Alan Kan
- Waisman Center, University of Wisconsin-Madison at the time this work was conducted. He is now with the School of Engineering, Macquarie University, NSW, Australia, 2109
| | - Qinglin Meng
- Acoustics Laboratory, School of Physics and Optoelectronics, South China University of Technology, Guangzhou, China, 510641
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D'Onofrio K, Richards V, Gifford R. Spatial Release From Informational and Energetic Masking in Bimodal and Bilateral Cochlear Implant Users. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2020; 63:3816-3833. [PMID: 33049147 PMCID: PMC8582905 DOI: 10.1044/2020_jslhr-20-00044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/27/2020] [Accepted: 07/24/2020] [Indexed: 06/11/2023]
Abstract
Purpose Spatially separating speech and background noise improves speech understanding in normal-hearing listeners, an effect referred to as spatial release from masking (SRM). In cochlear implant (CI) users, SRM has often been demonstrated using asymmetric noise configurations, which maximize benefit from head shadow and the potential availability of binaural cues. In contrast, SRM in symmetrical configurations has been minimal to absent in CI users. We examined the interaction between two types of maskers (informational and energetic) and SRM in bimodal and bilateral CI users. We hypothesized that SRM would be absent or "negative" using symmetrically separated noise maskers. Second, we hypothesized that bimodal listeners would exhibit greater release from informational masking due to access to acoustic information in the non-CI ear. Method Participants included 10 bimodal and 10 bilateral CI users. Speech understanding in noise was tested in 24 conditions: 3 spatial configurations (S0N0, S0N45&315, S0N90&270) × 2 masker types (speech, signal-correlated noise) × 2 listening configurations (best-aided, CI-alone) × 2 talker gender conditions (different-gender, same-gender). Results In support of our first hypothesis, both groups exhibited negative SRM with increasing spatial separation. In opposition to our second hypothesis, both groups exhibited similar magnitudes of release from informational masking. The magnitude of release was greater for bimodal listeners, though this difference failed to reach statistical significance. Conclusions Both bimodal and bilateral CI recipients exhibited negative SRM. This finding is consistent with CI signal processing limitations, the audiologic factors associated with SRM, and known effects of behind-the-ear microphone technology. Though release from informational masking was not significantly different across groups, the magnitude of release was greater for bimodal listeners. This suggests that bimodal listeners may be at least marginally more susceptible to informational masking than bilateral CI users, though further research is warranted.
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Affiliation(s)
- Kristen D'Onofrio
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, TN
| | | | - René Gifford
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, TN
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34
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Gajecki T, Nogueira W. The effect of synchronized linked band selection on speech intelligibility of bilateral cochlear implant users. Hear Res 2020; 396:108051. [DOI: 10.1016/j.heares.2020.108051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 07/07/2020] [Accepted: 07/14/2020] [Indexed: 10/23/2022]
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35
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Ausili SA, Agterberg MJH, Engel A, Voelter C, Thomas JP, Brill S, Snik AFM, Dazert S, Van Opstal AJ, Mylanus EAM. Spatial Hearing by Bilateral Cochlear Implant Users With Temporal Fine-Structure Processing. Front Neurol 2020; 11:915. [PMID: 33101160 PMCID: PMC7554532 DOI: 10.3389/fneur.2020.00915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/16/2020] [Indexed: 11/13/2022] Open
Abstract
Several studies have demonstrated the advantages of the bilateral vs. unilateral cochlear implantation in listeners with bilateral severe to profound hearing loss. However, it remains unclear to what extent bilaterally implanted listeners have access to binaural cues, e.g., accurate processing of interaural timing differences (ITDs) for low-frequency sounds (<1.5 kHz) and interaural level differences (ILDs) for high frequencies (>3 kHz). We tested 25 adult listeners, bilaterally implanted with MED-EL cochlear implant (CI) devices, with and without fine-structure (FS) temporal processing as encoding strategy in the low-frequency channels. In order to assess whether the ability to process binaural cues was affected by fine-structure processing, we performed psychophysical ILD and ITD sensitivity measurements and free-field sound localization experiments. We compared the results of the bilaterally implanted listeners with different numbers of FS channels. All CI listeners demonstrated good sensitivity to ILDs, but relatively poor to ITD cues. Although there was a large variability in performance, some bilateral CI users showed remarkably good localization skills. The FS coding strategy for bilateral CI hearing did not improve fine-structure ITD processing for spatial hearing on a group level. However, some CI listeners were able to exploit weakly informative temporal cues to improve their low-frequency spatial perception.
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Affiliation(s)
- Sebastián A Ausili
- Department of Biophysics, Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands.,Department of Otolaryngology, University of Miami, Miami, FL, United States
| | - Martijn J H Agterberg
- Department of Biophysics, Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands.,Department of Otorhinolaryngology, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Andreas Engel
- Department of Otorhinolaryngology Head and Neck Surgery, St. Elisabeth-Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Christiane Voelter
- Department of Otorhinolaryngology Head and Neck Surgery, St. Elisabeth-Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Jan Peter Thomas
- Department of Otorhinolaryngology Head and Neck Surgery, St. Elisabeth-Hospital, Ruhr-University Bochum, Bochum, Germany
| | | | - Ad F M Snik
- Department of Biophysics, Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Stefan Dazert
- Department of Otorhinolaryngology Head and Neck Surgery, St. Elisabeth-Hospital, Ruhr-University Bochum, Bochum, Germany
| | - A John Van Opstal
- Department of Biophysics, Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Emmanuel A M Mylanus
- Department of Otorhinolaryngology, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
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36
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Zhang Z, Wei C, Zhang Y, Zeng Z, Cao K, Liu Y. Sequential Bilateral Cochlear Implantation With Prolonged Time Intervals. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2020; 63:3195-3207. [PMID: 32857631 DOI: 10.1044/2020_jslhr-20-00140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Purpose The aim of the study was to assess whether sequential cochlear implantation (CI) with a prolonged interimplant interval (M = 15.2 years) between the first and second CIs benefited speech recognition and health-related quality of life. Method This prospective study included 14 prelingually deafened participants who received their second CI after a prolonged interimplant interval (M = 15.2 years). Additionally, speech recognition ability over a 12-month period of bilateral implant use was investigated. The results of the speech recognition test in both quiet and noisy conditions were statistically analyzed for each CI alone and both CIs together. Nijmegen Cochlear Implant Questionnaire scores were also collected at activation and at 12 months after activation. Results Improvements in speech recognition ability were observed following the use of the first implant alone and with the use of both implants together; however, progress was much slower with the use of the second implant alone, following its introduction. Furthermore, a significant difference in the trajectory of speech recognition ability was observed between the first and the second implanted ear. According to Nijmegen Cochlear Implant Questionnaire scores, all participants benefitted from bilateral CI after 12 months. Conclusions Prolonged interimplant intervals resulted in asymmetrical speech recognition abilities. A significant improvement in the speech recognition scores was observed with the first implanted ear, and much slower progress was observed with the second implanted ear. However, the "poorer" second implanted ear could provide a considerable beneficial effect on the improved speech recognition and health-related quality of life with the bilateral CI. Supplemental Material https://doi.org/10.23641/asha.12861152.
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Affiliation(s)
- Zhikai Zhang
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Chaogang Wei
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Yanmei Zhang
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Zhengang Zeng
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
| | - Keli Cao
- Department of Otorhinolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Peking Union Medical College, Beijing, China
| | - Yuhe Liu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing, China
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Warnecke M, Peng ZE, Litovsky RY. The impact of temporal fine structure and signal envelope on auditory motion perception. PLoS One 2020; 15:e0238125. [PMID: 32822439 PMCID: PMC7446836 DOI: 10.1371/journal.pone.0238125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 08/10/2020] [Indexed: 02/02/2023] Open
Abstract
The majority of psychoacoustic research investigating sound localization has utilized stationary sources, yet most naturally occurring sounds are in motion, either because the sound source itself moves, or the listener does. In normal hearing (NH) listeners, previous research showed the extent to which sound duration and velocity impact the ability of listeners to detect sound movement. By contrast, little is known about how listeners with hearing impairments perceive moving sounds; the only study to date comparing the performance of NH and bilateral cochlear implant (BiCI) listeners has demonstrated significantly poorer performance on motion detection tasks in BiCI listeners. Cochlear implants, auditory protheses offered to profoundly deaf individuals for access to spoken language, retain the signal envelope (ENV), while discarding temporal fine structure (TFS) of the original acoustic input. As a result, BiCI users do not have access to low-frequency TFS cues, which have previously been shown to be crucial for sound localization in NH listeners. Instead, BiCI listeners seem to rely on ENV cues for sound localization, especially level cues. Given that NH and BiCI listeners differentially utilize ENV and TFS information, the present study aimed to investigate the usefulness of these cues for auditory motion perception. We created acoustic chimaera stimuli, which allowed us to test the relative contributions of ENV and TFS to auditory motion perception. Stimuli were either moving or stationary, presented to NH listeners in free field. The task was to track the perceived sound location. We found that removing low-frequency TFS reduces sensitivity to sound motion, and fluctuating speech envelopes strongly biased the judgment of sounds to be stationary. Our findings yield a possible explanation as to why BiCI users struggle to identify sound motion, and provide a first account of cues important to the functional aspect of auditory motion perception.
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Affiliation(s)
- Michaela Warnecke
- University of Wisconsin-Madison, Waisman Center, Madison, WI, United States of America
| | - Z. Ellen Peng
- University of Wisconsin-Madison, Waisman Center, Madison, WI, United States of America
| | - Ruth Y. Litovsky
- University of Wisconsin-Madison, Waisman Center, Madison, WI, United States of America
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Fletcher MD, Song H, Perry SW. Electro-haptic stimulation enhances speech recognition in spatially separated noise for cochlear implant users. Sci Rep 2020; 10:12723. [PMID: 32728109 PMCID: PMC7391652 DOI: 10.1038/s41598-020-69697-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/14/2020] [Indexed: 11/10/2022] Open
Abstract
Hundreds of thousands of profoundly hearing-impaired people perceive sounds through electrical stimulation of the auditory nerve using a cochlear implant (CI). However, CI users are often poor at understanding speech in noisy environments and separating sounds that come from different locations. We provided missing speech and spatial hearing cues through haptic stimulation to augment the electrical CI signal. After just 30 min of training, we found this “electro-haptic” stimulation substantially improved speech recognition in multi-talker noise when the speech and noise came from different locations. Our haptic stimulus was delivered to the wrists at an intensity that can be produced by a compact, low-cost, wearable device. These findings represent a significant step towards the production of a non-invasive neuroprosthetic that can improve CI users’ ability to understand speech in realistic noisy environments.
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Affiliation(s)
- Mark D Fletcher
- University of Southampton Auditory Implant Service, University of Southampton, University Road, Southampton, SO17 1BJ, UK.
| | - Haoheng Song
- Faculty of Engineering and Physical Sciences, University of Southampton, University Road, Southampton, SO17 1BJ, UK
| | - Samuel W Perry
- University of Southampton Auditory Implant Service, University of Southampton, University Road, Southampton, SO17 1BJ, UK
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Valzolgher C, Campus C, Rabini G, Gori M, Pavani F. Updating spatial hearing abilities through multisensory and motor cues. Cognition 2020; 204:104409. [PMID: 32717425 DOI: 10.1016/j.cognition.2020.104409] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 10/23/2022]
Abstract
Spatial hearing relies on a series of mechanisms for associating auditory cues with positions in space. When auditory cues are altered, humans, as well as other animals, can update the way they exploit auditory cues and partially compensate for their spatial hearing difficulties. In two experiments, we simulated monaural listening in hearing adults by temporarily plugging and muffing one ear, to assess the effects of active or passive training conditions. During active training, participants moved an audio-bracelet attached to their wrist, while continuously attending to the position of the sounds it produced. During passive training, participants received identical acoustic stimulation and performed exactly the same task, but the audio-bracelet was moved by the experimenter. Before and after training, we measured adaptation to monaural listening in three auditory tasks: single sound localization, minimum audible angle (MAA), spatial and temporal bisection. We also performed the tests twice in an untrained group, which completed the same auditory tasks but received no training. Results showed that participants significantly improved in single sound localization, across 3 consecutive days, but more in the active compared to the passive training group. This reveals that benefits of kinesthetic cues are additive with respect to those of paying attention to the position of sounds and/or seeing their positions when updating spatial hearing. The observed adaptation did not generalize to other auditory spatial tasks (space bisection and MAA), suggesting that partial updating of sound-space correspondences does not extend to all aspects of spatial hearing.
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Affiliation(s)
- Chiara Valzolgher
- Centro Interdipartimentale Mente/Cervello (CIMeC), University of Trento, Italy; IMPACT, Centre de Recherche en Neurosciences Lyon (CRNL), France.
| | | | - Giuseppe Rabini
- Centro Interdipartimentale Mente/Cervello (CIMeC), University of Trento, Italy
| | - Monica Gori
- Italian Institute of Technology (IIT), Italy
| | - Francesco Pavani
- Centro Interdipartimentale Mente/Cervello (CIMeC), University of Trento, Italy; IMPACT, Centre de Recherche en Neurosciences Lyon (CRNL), France; Department of Psychology and Cognitive Science, Universiy of Trento, Italy
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Visentin C, Pellegatti M, Prodi N. Effect of a single lateral diffuse reflection on spatial percepts and speech intelligibility. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 148:122. [PMID: 32752761 DOI: 10.1121/10.0001527] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/20/2020] [Indexed: 06/11/2023]
Abstract
This study examines the influence of an early lateral reflection on spatial perceptual attributes and speech reception. To this aim, a diffuse reflection is compared with a specular one. Although diffusive surfaces have widespread applications in room acoustics design, the knowledge of the perceptual and behavioral outcomes of these surfaces has yet to be fully developed. Two experiments were conducted to investigate how the reflection type, its temporal delay, and its azimuth affect spatial percepts (source distance, width, and focus) and speech intelligibility (SI) in diffuse stationary noise. The experimental setup included ecological elements: field measurements, a speaker-like source directivity, and real flat and diffusive surfaces. The results indicate that the presence of a single diffuse reflection reduces the perceived distance of a frontal speech source and makes it clearer. SI is higher with a diffuse reflection than with a specular one. Perceptual and behavioral outcomes both depend on the angle of reflection given the frequency- and angular-dependent properties of the diffusing surface and the directivity of the speech source. The results are interpreted with reference to loudness and binaural cues and to the precedence effect. Implications of the findings for acoustic design are also discussed.
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Affiliation(s)
- Chiara Visentin
- Department of Engineering, University of Ferrara, Ferrara, Italy
| | | | - Nicola Prodi
- Department of Engineering, University of Ferrara, Ferrara, Italy
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41
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Potrusil T, Heshmat A, Sajedi S, Wenger C, Johnson Chacko L, Glueckert R, Schrott-Fischer A, Rattay F. Finite element analysis and three-dimensional reconstruction of tonotopically aligned human auditory fiber pathways: A computational environment for modeling electrical stimulation by a cochlear implant based on micro-CT. Hear Res 2020; 393:108001. [PMID: 32535276 DOI: 10.1016/j.heares.2020.108001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 05/14/2020] [Accepted: 05/23/2020] [Indexed: 01/01/2023]
Abstract
The application of cochlear implants can be studied with computational models. The electrical potential distribution induced by an implanted device is evaluated with a volume conductor model, which is used as input for neuron models to simulate the reaction of cochlear neurons to micro-stimulation. In order to reliably predict the complex excitation profiles it is vital to consider an accurate representation of the human cochlea geometry including detailed three-dimensional pathways of auditory neurons reaching from the organ of Corti through the cochlea-volume. In this study, high-resolution micro-CT imaging (Δx = Δy = Δz = 3 μm) was used to reconstruct the pathways of 30 tonotopically organized nerve fiber bundles, distributed over eight octaves (11500-40 Hz). Results of the computational framework predict: (i) the peripheral process is most sensitive to cathodic stimulation (CAT), (ii) in many cases CAT elicits spikes in the peripheral terminal at threshold but with larger stimuli there is a second spike initiation site within the peripheral process, (iii) anodic stimuli (ANO) can excite the central process even at threshold, (iv) the recruitment of fibers by electrodes located in the narrowing middle- and apical turn is complex and impedes focal excitation of low frequency fibers, (v) degenerated cells which lost the peripheral process are more sensitive to CAT when their somata are totally covered with 2 membranes of a glial cell but they become ANO sensitive when the myelin covering is reduced.
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Affiliation(s)
- Thomas Potrusil
- Innsbruck Medical University, Department of Otorhinolaryngology, Laboratory for Inner Ear Biology, Anichstrasse 35, A-6020, Innsbruck, Austria
| | - Amirreza Heshmat
- Innsbruck Medical University, Department of Otorhinolaryngology, Laboratory for Inner Ear Biology, Anichstrasse 35, A-6020, Innsbruck, Austria; TU Wien, Institute for Analysis and Scientific Computing, Wiedner Hauptstraße 8-10, A- 1040, Vienna, Austria
| | - Sogand Sajedi
- TU Wien, Institute for Analysis and Scientific Computing, Wiedner Hauptstraße 8-10, A- 1040, Vienna, Austria
| | - Cornelia Wenger
- TU Wien, Institute for Analysis and Scientific Computing, Wiedner Hauptstraße 8-10, A- 1040, Vienna, Austria
| | - Lejo Johnson Chacko
- Innsbruck Medical University, Department of Otorhinolaryngology, Laboratory for Inner Ear Biology, Anichstrasse 35, A-6020, Innsbruck, Austria
| | - Rudolf Glueckert
- Innsbruck Medical University, Department of Otorhinolaryngology, Laboratory for Inner Ear Biology, Anichstrasse 35, A-6020, Innsbruck, Austria
| | - Anneliese Schrott-Fischer
- Innsbruck Medical University, Department of Otorhinolaryngology, Laboratory for Inner Ear Biology, Anichstrasse 35, A-6020, Innsbruck, Austria.
| | - Frank Rattay
- TU Wien, Institute for Analysis and Scientific Computing, Wiedner Hauptstraße 8-10, A- 1040, Vienna, Austria
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Moore BCJ. Effects of hearing loss and age on the binaural processing of temporal envelope and temporal fine structure information. Hear Res 2020; 402:107991. [PMID: 32418682 DOI: 10.1016/j.heares.2020.107991] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/24/2020] [Accepted: 05/05/2020] [Indexed: 11/28/2022]
Abstract
Within the cochlea, broadband sounds like speech and music are filtered into a series of narrowband signals, each with a relatively slowly varying envelope (ENV) imposed on a rapidly oscillating carrier (the temporal fine structure, TFS). Information about ENV is conveyed by the timing and short-term rate of action potentials in the auditory nerve while information about TFS is conveyed by synchronization of action potentials to a specific phase of the waveform in the cochlea (phase locking). This paper describes the effects of age and hearing loss on the binaural processing of ENV and TFS information, i.e. on the processing of differences in ENV and TFS at the two ears. The binaural processing of TFS information is adversely affected by both hearing loss and increasing age. The binaural processing of ENV information deteriorates somewhat with increasing age but is only slightly affected by hearing loss. The reduced TFS processing abilities found for older/hearing-impaired subjects may partially account for the difficulties that such subjects experience in complex listening situations when the target speech and interfering sounds come from different directions in space.
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Affiliation(s)
- Brian C J Moore
- Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge, CB2 3EB, UK.
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43
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Ciorba A, Guidi MP, Skarżyński PH, Bianchini C, Rosignoli M, Mazzoli M, Pelucchi S, Hatzopoulos S. Rehabilitation of Severe to Profound Sensorineural Hearing Loss in Adults: Audiological Outcomes. EAR, NOSE & THROAT JOURNAL 2019; 100:215S-219S. [PMID: 31838921 DOI: 10.1177/0145561319892461] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The aim of this article is to describe the audiological patterns of 71 adult patients presenting severe to profound sensorineural hearing loss, who were rehabilitated by cochlear implants (CIs) and hearing aids. This is a retrospective study in a university setting, where the clinical records of 71 adult patients were reviewed and processed. Speech intelligibility was evaluated at one aided ear (CI) or at both aided ears (double CI or a combination of CI and hearing aid [HA]). Patients with a bilateral CI or with a bimodal hearing setup (CI and HA) performed better than those with a single CI; data from the phonetic matrices test showed that there was a statistically significant difference among patients aided by a single CI versus binaural setup (double CI or CI + HA). In particular, patients aided by a bilateral CI, or by a CI and HA, showed an improvement in the functional results of the speech tests, compared to patients using a single CI. Binaural hearing (either with a bilateral CI or bimodal) allows an improvement in the functional results at the speech tests, compared to the use of a CI only.
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Affiliation(s)
- Andrea Ciorba
- ENT and Audiology Clinic, University of Ferrara, Ferrara, Italy
| | | | - Piotr H Skarżyński
- Institute of Physiology and Pathology of Hearing, Warsaw, Poland.,Department of Heart Failure and Cardiac Rehabilitation, Medical University of Warsaw, Warsaw, Poland.,Institute of Sensory Organs, Kajetany, Poland
| | | | | | - Manuela Mazzoli
- ENT and Audiology Clinic, University of Ferrara, Ferrara, Italy
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Erdem BK, Çiprut A. Evaluation of Speech, Spatial Perception and Hearing Quality in Unilateral, Bimodal and Bilateral Cochlear Implant Users. Turk Arch Otorhinolaryngol 2019; 57:149-153. [PMID: 31620697 DOI: 10.5152/tao.2019.4105] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/02/2019] [Indexed: 11/22/2022] Open
Abstract
Objective The aim of the study was to conduct a scale-based evaluation of the hearing skills of unilateral, bimodal and bilateral cochlear implant (CI) users, including distinguishing, orientating and locating speech and environmental sounds in their surrounding environment that they are exposed to in different contexts of everyday life. The scale results were compared between groups. Methods A total of 74 cochlear implant users, 30 unilateral, 30 bimodal and 14 bilateral, were included in the study. Their ages ranged from 11 to 64 years. Participants were assessed using the Speech, Spatial and Qualities of Hearing Scale (SSQ). Results Bilateral CI users' subjective ratings of their own hearing skills were found to be significantly better than those of bimodal and unilateral CI users; bimodal users' subjective ratings were also found to be significantly better than those of unilateral CI users. Paired comparisons showed statistically significant differences between the groups in terms of total scores of Speech, Spatial, Qualities of Hearing and General SSQ (p<0.05). Conclusion Our findings show that bilateral use of cochlear implants should be recommended for those presently using bimodal and unilateral devices. Moreover, subjective tests should be used regularly along with objective tests for evaluating CI patients.
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Affiliation(s)
- Büşra Koçak Erdem
- Department of Audiology, Lütfi Kırdar Training and Research Hospital, İstanbul, Turkey
| | - Ayça Çiprut
- Department of Audiology, Marmara University School of Medicine, İstanbul, Turkey
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45
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Au A, Dowell RC. Evidence-Based Recommendation for Bilateral Cochlear Implantation in Adults. Am J Audiol 2019; 28:775-782. [PMID: 32271119 DOI: 10.1044/2019_aja-heal18-18-0183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Purpose Most adult cochlear implant (CI) users in developed countries benefit from the use of a hearing aid in conjunction with their implant device (bimodal hearing). Benefits have also been documented for the use of bilateral CIs for speech perception in quiet, localization, and speech perception in noise. This study attempted to quantify speech perception results for bimodal and bilateral CIs in adults and provide a guide for those considering a 2nd CI. Method Speech perception outcomes were reviewed for 1,394 adults with acquired hearing loss who received a CI at the Melbourne Cochlear Implant Clinic between 2000 and 2015. Results Bimodal and bilateral users significantly outperformed unilateral CI users on consonant-vowel-consonant word recognition in quiet. For the bilateral group, word recognition scores with the 1st CI were predictive of 2nd CI word scores. The analysis suggested that bimodal users who were gaining less than 19% benefit from the nonimplanted ear were likely to perform better with a 2nd implant. Conclusions CI users who score less than 19% on consonant-vowel-consonant words in the nonimplanted ear have a good chance of benefiting from a 2nd implant. Consideration of many other factors including age, hearing goals, medical factors, and the risk to residual hearing also needs to play a part in recommending a 2nd CI.
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Affiliation(s)
- Agnes Au
- The HEARing Cooperative Research Center, Melbourne, Victoria, Australia
- Department of Audiology and Speech Pathology, The University of Melbourne, Victoria, Australia
| | - Richard C. Dowell
- The HEARing Cooperative Research Center, Melbourne, Victoria, Australia
- Department of Audiology and Speech Pathology, The University of Melbourne, Victoria, Australia
- Cochlear Implant Clinic, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
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Kan A, Goupell MJ, Litovsky RY. Effect of channel separation and interaural mismatch on fusion and lateralization in normal-hearing and cochlear-implant listeners. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:1448. [PMID: 31472555 PMCID: PMC6713556 DOI: 10.1121/1.5123464] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 08/05/2019] [Accepted: 08/05/2019] [Indexed: 05/29/2023]
Abstract
Bilateral cochlear implantation has provided access to some of the benefits of binaural hearing enjoyed by normal-hearing (NH) listeners. However, a gap in performance still exists between the two populations. Single-channel stimulation studies have shown that interaural place-of-stimulation mismatch (IPM) due to differences in implantation depth leads to decreased binaural fusion and lateralization of interaural time and level differences (ITDs and ILDs, respectively). While single-channel studies are informative, multi-channel stimulation is needed for good speech understanding with cochlear implants (CIs). Some multi-channel studies have shown that channel interaction due to current spread can affect ITD sensitivity. In this work, we studied the effect of IPM and channel spacing, along with their potential interaction, on binaural fusion and ITD/ILD lateralization. Experiments were conducted in adult NH listeners and CI listeners with a history of acoustic hearing. Results showed that IPM reduced the range of lateralization for ITDs but not ILDs. CI listeners were more likely to report a fused percept in the presence of IPM with multi-channel stimulation than NH listeners. However, no effect of channel spacing was found. These results suggest that IPM should be accounted for in clinical mapping practices in order to maximize bilateral CI benefits.
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Affiliation(s)
- Alan Kan
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, Wisconsin 53705, USA
| | - Matthew J Goupell
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Ruth Y Litovsky
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, Wisconsin 53705, USA
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Alnıaçık A, Akdaş F. The effects of adaptive directional microphone on auditory evoked cortical P300 response and speech performance in cochlear implant users. Int J Audiol 2019; 58:861-868. [PMID: 31268365 DOI: 10.1080/14992027.2019.1637028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objective: The aim of this study was to evaluate the possible benefits of an adaptive directional microphone in noise by using auditory P300 and speech recognition scores (SRSs) in cochlear implant subjects.Design: The P300 and speech recognition scores were obtained (a) in quiet with an omnidirectional microphone (Quiet OM), (b) in noise with an omnidirectional microphone (Noise OM) and (c) in noise with an adaptive directional microphone (Noise BEAM) to compare the microphone effects.Study sample: Thirty-five cochlear implant subjects (22.87 ± 1.30 years)Results: The latencies of the P2, N2 and P3 responses as the discrimination potentials were significantly prolonged in the Noise OM condition compared with those obtained in the Quiet OM and Noise BEAM conditions (p < 0.05). The latencies of all responses in the Quiet OM and Noise BEAM conditions were similarly obtained (p > 0.05). SRSs were significantly lower in the Noise OM condition than in the Quiet OM and Noise BEAM condition (p < 0.05).Conclusions: During noise, the adaptive directional microphone system provided a discrimination ability similar to that seen in quiet settings for cochlear implant users.
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Affiliation(s)
| | - Ferda Akdaş
- Department of Audiology, Marmara University, Istanbul, Turkey
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Wells B, Beeston AV, Bradley E, Brown GJ, Crook H, Kurtić E. Talking in Time: The development of a self-administered conversation analysis based training programme for cochlear implant users. Cochlear Implants Int 2019; 20:255-265. [PMID: 31234737 DOI: 10.1080/14670100.2019.1625185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objectives: Training software to facilitate participation in conversations where overlapping talk is common was to be developed with the involvement of Cochlear implant (CI) users. Methods: Examples of common types of overlap were extracted from a recorded corpus of 3.5 hours of British English conversation. In eight meetings, an expert panel of five CI users tried out ideas for a computer-based training programme addressing difficulties in turn-taking. Results: Based on feedback from the panel, a training programme was devised. The first module consists of introductory videos. The three remaining modules, implemented in interactive software, focus on non-overlapped turn-taking, competitive overlaps and accidental overlaps. Discussion: The development process is considered in light of feedback from panel members and from an end of project dissemination event. Benefits, limitations and challenges of the present approach to user involvement and to the design of self-administered communication training programmes are discussed. Conclusion: The project was characterized by two innovative features: the involvement of service users not only at its outset and conclusion but throughout its course; and the exclusive use of naturally occurring conversational speech in the training programme. While both present practical challenges, the project has demonstrated the potential for ecologically valid speech rehabilitation training.
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Affiliation(s)
- Bill Wells
- a Department of Human Communication Sciences , University of Sheffield , Sheffield , UK
| | - Amy V Beeston
- b Department of Computer Science , University of Sheffield , Sheffield , UK
| | - Erica Bradley
- c Department of Neurotology , Sheffield Teaching Hospitals NHS Trust , Sheffield , UK
| | - Guy J Brown
- b Department of Computer Science , University of Sheffield , Sheffield , UK
| | - Harriet Crook
- c Department of Neurotology , Sheffield Teaching Hospitals NHS Trust , Sheffield , UK
| | - Emina Kurtić
- a Department of Human Communication Sciences , University of Sheffield , Sheffield , UK
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Sharma S, Mens LHM, Snik AFM, van Opstal AJ, van Wanrooij MM. An Individual With Hearing Preservation and Bimodal Hearing Using a Cochlear Implant and Hearing Aids Has Perturbed Sound Localization but Preserved Speech Perception. Front Neurol 2019; 10:637. [PMID: 31293495 PMCID: PMC6598447 DOI: 10.3389/fneur.2019.00637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 05/30/2019] [Indexed: 11/13/2022] Open
Abstract
This study describes sound localization and speech-recognition-in-noise abilities of a cochlear-implant user with electro-acoustic stimulation (EAS) in one ear, and a hearing aid in the contralateral ear. This listener had low-frequency, up to 250 Hz, residual hearing within the normal range in both ears. The objective was to determine how hearing devices affect spatial hearing for an individual with substantial unaided low-frequency residual hearing. Sound-localization performance was assessed for three sounds with different bandpass characteristics: low center frequency (100-400 Hz), mid center frequency (500-1,500 Hz) and high frequency broad-band (500-20,000 Hz) noise. Speech recognition was assessed with the Dutch Matrix sentence test presented in noise. Tests were performed while the listener used several on-off combinations of the devices. The listener localized low-center frequency sounds well in all hearing conditions, but mid-center frequency and high frequency broadband sounds were localized well almost exclusively in the completely unaided condition (mid-center frequency sounds were also localized well with the EAS device alone). Speech recognition was best in the fully aided condition with speech presented in the front and noise presented at either side. Furthermore, there was no significant improvement in speech recognition with all devices on, compared to when the listener used her cochlear implant only. Hearing aids and cochlear implant impair high frequency spatial hearing due to improper weighing of interaural time and level difference cues. The results reinforce the notion that hearing symmetry is important for sound localization. The symmetry is perturbed by the hearing devices for higher frequencies. Speech recognition depends mainly on hearing through the cochlear implant and is not significantly improved with the added information from hearing aids. A contralateral hearing aid provides benefit when the noise is spatially separated from the speech. However, this benefit is explained by the head shadow in that ear, rather than by an ability to spatially segregate noise from speech, as sound localization was perturbed with all devices in use.
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Affiliation(s)
- Snandan Sharma
- Department of Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, Netherlands
| | - Lucas H M Mens
- Department of Otorhinolaryngology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Ad F M Snik
- Department of Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, Netherlands
| | - A John van Opstal
- Department of Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, Netherlands
| | - Marc M van Wanrooij
- Department of Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, Netherlands
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Heidekrüger N, Rahne T, Wagner L. [Processing of interaural time differences in normal-hearing subjects and cochlear implant users with FSP and HDCIS coding strategy]. HNO 2019; 67:855-862. [PMID: 31201511 DOI: 10.1007/s00106-019-0699-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Sound localization is necessary for social interaction and remains challenging for bilateral cochlear implant (CI) users. This study investigated the influence of fine structure processing (FSP) coding strategies on temporal accuracy and source localization. The ability to discriminate between different interaural time differences (ITD) was measured objectively and compared. MATERIALS AND METHODS Fifteen normal-hearing subjects and five CI users participated in this study. Electrophysiological recording of mismatch negativity (MMN) and psychoacoustic tests with headphones and loudspeakers were conducted to measure and compare the discrimination of ITDs. RESULTS In normal-hearing subjects the discrimination threshold for ITD was 83-117 µs. Localization ability in a free sound field was below the limit of resolution. A significant MMN was measured. CI users showed a mean angle detection error of more than 30° and a discrimination threshold between 1100 and 2100 µs. Due to artifacts, no clear MMN component could be recorded. CONCLUSION This study shows that MMN can be used as an objective measure of ITD discrimination in normal-hearing participants. An indication that improvements in directional hearing can be achieved with the transfer of fine structure could not be provided by this study.
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Affiliation(s)
- N Heidekrüger
- Universitätsklinik und Poliklinik für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie, Universitätsklinikum Halle (Saale), Universitätsmedizin Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland.
| | - T Rahne
- Universitätsklinik und Poliklinik für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie, Universitätsklinikum Halle (Saale), Universitätsmedizin Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland
| | - L Wagner
- Universitätsklinik und Poliklinik für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie, Universitätsklinikum Halle (Saale), Universitätsmedizin Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland
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