Intonational cues for speech perception in noise by cochlear implant listeners.

The aim of the study was to investigate the link between temporal fine structure (TFS) processing, pitch, and speech perception performance in adult cochlear implant (CI) recipients, including bimodal listeners who may benefit better low-frequency (LF) temporal coding in the contralateral ear. The study participants were 43 adult CI recipients (23 unilateral, 6 bilateral, and 14 bimodal listeners). Two new LF pitch perception tests-harmonic intonation (HI) and disharmonic intonation (DI)-were used to evaluate TFS sensitivity. HI and DI were designed to estimate a difference limen for discrimination of tone changes based on harmonic or inharmonic pitch glides. Speech perception was assessed using the newly developed Italian Sentence Test with Adaptive Randomized Roving level (STARR) test where sentences relevant to everyday contexts were presented at low, medium, and high levels in a fluctuating background noise to estimate a speech reception threshold (SRT). Although TFS and STARR performances in the majority of CI recipients were much poorer than those of hearing people reported in the literature, a considerable intersubject variability was observed. For CI listeners, median just noticeable differences were 27.0 and 147.0 Hz for HI and DI, respectively. HI outcomes were significantly better than those for DI. Median STARR score was 14.8 dB. Better performers with speech reception thresholds less than 20 dB had a median score of 8.6 dB. A significant effect of age was observed for both HI/DI tests, suggesting that TFS sensitivity tended to worsen with increasing age. CI pure-tone thresholds and duration of profound deafness were significantly correlated with STARR performance. Bimodal users showed significantly better TFS and STARR performance for bimodal listening than for their CI-only condition. Median bimodal gains were 33.0 Hz for the HI test and 95.0 Hz for the DI test. DI outcomes in bimodal users revealed a significant correlation with unaided hearing thresholds for octave frequencies lower than 1000 Hz. Median STARR scores were 17.3 versus 8.1 dB for CI only and bimodal listening, respectively. STARR performance was significantly correlated with HI findings for CI listeners and with those of DI for bimodal listeners. LF pitch perception was found to be abnormal in the majority of adult CI recipients, confirming poor TFS processing of CIs. Similarly, the STARR findings reflected a common performance deterioration with the HI/DI tests, suggesting the cause probably being a lack of access to TFS information. Contralateral hearing aid users obtained a remarkable bimodal benefit for all tests. Such results highlighted the importance of TFS cues for challenging speech perception and the relevance to everyday listening conditions. HI/DI and STARR tests show promise for gaining insights into how TFS and speech perception are being limited and may guide the customization of CI program parameters and support the fine tuning of bimodal listening.

There is a lack of high level of evidence studies comparing the effect of different treatment options for single-sided deafness (SSD). To determine the effect of a cochlear implant (CI), bone conduction device (BCD), contralateral routing of signals hearing aid (CROS), and no treatment on speech perception in noise outcomes in patients with SSD. In this single-center randomized clinical trial, adult patients with SSD were randomized into 3 groups: CI; a trial period with first a BCD on a headband and then a CROS; or a trial period with first a CROS and then a BCD on a headband. After the trial periods, patients opted for a BCD, CROS, or no treatment. Measurements were completed at baseline and at 3, 6, 12, and 24 months of follow-up. Data were collected from July 2014 to October 2021, and data were analyzed from December 2022 to May 2023. CI, BCD then CROS, or CROS then BCD. The primary outcome was the speech reception threshold in noise (SRTn), measured with speech and noise from the front (S0N0), speech directed to the poor ear and noise to the better ear (SpeNbe), and vice versa (SbeNpe). The secondary outcome was disease-specific quality of life (QOL). Of 120 included patients, 60 (50.0%) were female, and the mean (SD) age at inclusion was 53.0 (12.1) years. At the start of follow-up, 28 patients received a CI, 25 a BCD, 34 a CROS, and 26 chose no treatment. At 24 months, the CI group had significantly better speech perception in noise scores than the BCD group (difference in SRTn: SbeNpe, -4.7 dB; 95% confidence interval, -6.6 to -3.0; SpeNbe, -2.2 dB; 95% confidence interval, -4.6 to -1.1), the CROS group (difference in SRTn: S0N0, -1.3 dB; 95% confidence interval, -1.7 to -0.2; SbeNpe, -5.3 dB; 95% confidence interval, -6.0 to -3.1), and the no treatment group (difference in SRTn: SpeNbe, -6.3 dB; 95% confidence interval, -7.5 to -4.9). Compared with the no treatment group, the BCD and CROS groups showed significantly better (difference in SRTn for SpeNbe, -4.1 dB [95% confidence interval, -5.2 to -1.5] and -4.1 dB [95% confidence interval, -6.1 to -3.3], respectively) or worse (difference for SbeNpe, 4.0 dB [95% confidence interval, 2.6 to 6.2] and 4.6 dB [95% confidence interval, 2.8 to 5.7], respectively) speech perception in noise. Self-reported speech perception abilities were significantly better for the CI group compared with the BCD, CROS, and no treatment groups. In this randomized clinical trial, the CI group outperformed the BCD, CROS, and no treatment groups in terms of speech perception in noise and disease-specific QOL in patients with SSD after 24 months of follow-up. These results indicate that patients with SSD can partially regain the advantages of binaural hearing after treatment. trialregister.nl Identifier: NL4457.

The Use of Listening Devices to Ameliorate Auditory Deficit in Children with Autism

Aims: To investigate the long-term effects of the fine structure processing (FSP) coding strategy on speech perception in noise and quality of life in experienced cochlear implant (CI) users. Methods: In a prospective comparative clinical trial, 32 experienced postlingually deafened CI recipients were upgraded from the Tempo+ to the Opus 2 audio processor, implementing FSP in one group and high-definition continuous interleaved sampling (HDCIS) coding strategy in another group with identical frequency ranges. Speech perception in noise testing and the Speech, Spatial and Qualities (SSQ) questionnaire were administered at 0, 6, 12 and 24 months after the upgrade. Results: FSP yielded significant long-term improvement of speech perception in noise of in total 13.2 dB from 16.2 dB SNR at the upgrade to 3.0 dB SNR after 24 months of FSP experience. No significant improvement of speech perception in noise over time was measured for the HDCIS group. With the SSQ questionnaire, a significant benefit of the FSP coding strategy was observed. Conclusions: The FSP coding strategy as implemented in the Med-EL Opus 2 audio processor improves speech perception in noise. This beneficial effect of FSP on speech perception in noise is not immediate but is significant after 12 months and further improves up to 24 months after implementation of FSP.

The main objective of this study was to examine the effect of a classifier-based noise management algorithm (AutoSense Sky OS 3.0) on speech perception in noise in pediatric cochlear implant (CI) recipients and to compare the speech perception outcomes with typically hearing peers. This prospective observational study included nine children (ages 9-15 years) with bilateral CIs and nine age-matched, typically hearing peers. Speech perception outcomes were measured in noise using Pediatric AzBio sentences to compare performance in the omnidirectional microphone mode with the classifier-based automatic noise management mode at four signal-to-noise ratios. Ratings of listening ease and speech clarity were recorded to obtain subjective measures of benefit. Results from the bilateral CI recipients were compared to a group of typically hearing children. Paired t tests were used to evaluate outcomes. Classifier-based noise management improved speech perception in noise compared to listening in the omnidirectional microphone mode. CI group averages revealed a 21.4 percentage point and 47.1 percentage point improvement in speech perception when using the Sky OS 3.0 algorithm at 0 and -5 dB SNR, respectively. Listening ease and speech clarity were improved when using the classifier-based noise management algorithm. Pediatric CI recipients can benefit from classifier-based noise management. Given the difficult listening environments children face, especially in typical classroom settings while listening for learning, audiologists should consider activating classifier-based noise management in this population.

Objectives:Children with prelingual single-sided deafness (SSD) have difficulty understanding speech in noise and sound localization. They also have an increased risk of problems with their language and cognitive development. Moreover, untreated SSD can lead to cortical reorganization, that is, the aural preference syndrome. Providing these children with a cochlear implant (CI) at an early age may support improved outcomes across multiple domains. This longitudinal study aimed to identify those aspects of development that are especially at risk in children with SSD, and to determine whether early cochlear implantation affects the children’s developmental outcomes.Design:Over the past decade, 37 children with SSD completed regular auditory, language, cognitive, and balance assessments. Twenty of these children received a CI before the age of 2.5 yr. The same developmental outcomes were assessed in 33 children with bilateral normal hearing who served as a control group. The present study describes spatial hearing, cognitive, and postural balance development outcomes. These were assessed using standardized tests for speech perception in noise (speech reception threshold in three spatial conditions), sound localization (mean localization error in a nine-loudspeaker set-up), cognitive skills (Wechsler Preschool and Primary Scale of Intelligence), balance (Bruininks-Oseretsky Test of Motor Proficiency), and preoperative cervical vestibular evoked myogenic potentials.Results:Longitudinal analysis showed that the children with SSD who did not receive a CI were at risk for poorer speech perception in noise, sound localization, and verbal intelligence quotient. On average, they had higher speech perception thresholds (1.6 to 16.8 dB, depending on the spatial condition), larger localization errors (35.4°), and lower verbal intelligence quotient scores (difference of 0.78 standard deviations). Children with SSD with a CI performed on par with the normal hearing children on the cognitive tests. In addition, they outperformed their nonimplanted peers with SSD on tests for speech perception in noise (up to 11.1 dB lower mean speech reception threshold, depending on spatial condition) and sound localization (9.5° smaller mean error). The children with SSD, with and without a CI achieved similar scores on behavioral tasks for postural balance.Conclusions:The present study shows that early cochlear implantation can improve spatial hearing outcomes and facilitate typical neurocognitive development in children with prelingual SSD. Taken together with previously published data related to children’s language development, the present results confirm that children with prelingual SSD can benefit from a CI provided at an early age to support their development across multiple domains. Several guidelines are suggested regarding the clinical follow-up and rehabilitation of these children.

The temporal fine structure (TFS) of sound contributes significantly to the perception of music and speech in noise. The evaluation of new strategies to improve TFS delivery in cochlear implants (CIs) relies upon the assessment of fine structure encoding. Most modern CI sound processing schemes do not encode within-channel TFS per se, but some TFS information is delivered through temporal envelope cues across multiple channels. Positive and negative Schroeder-phase harmonic complexes differ primarily in acoustic TFS and provide a potential test of TFS discrimination ability in CI users for current and future processing strategies. The ability to discriminate Schroeder-phase stimuli was evaluated in 24 CI users and 7 normal-hearing listeners at four fundamental frequencies: 50, 100, 200, and 400 Hz. The dependent variables were percent correct at each fundamental frequency, average score across all fundamental frequencies, and a maximum-likelihood-predicted threshold fundamental frequency for 75% correct. CI listeners scored better than chance for all fundamental frequencies tested. The 50-Hz, average, and predicted threshold scores correlated significantly with consonant-nucleus-consonant word scores. The 200-Hz score correlated with a measure of speech perception in speech-shaped noise. Pitch-direction sensitivity is predicted jointly by the 400-Hz Schroeder score and a spectral ripple discrimination task. The results demonstrate that the Schroeder test is a potentially useful measure of clinically relevant temporal processing abilities in CI users.

IntroductionThe frequency modulation system is a device that helps to improve speech perception in noise and is considered the most beneficial approach to improve speech recognition in noise in cochlear implant users. According to guidelines, there is a need to perform a check before fitting the frequency modulation system. Although there are recommendations regarding the behavioral tests that should be performed at the fitting of the frequency modulation system to cochlear implant users, there are no published recommendations regarding the electroacoustic test that should be performed. ObjectivePerform and determine the validity of an electroacoustic verification test for frequency modulation systems coupled to different cochlear implant speech processors. MethodsThe sample included 40 participants between 5 and 18 year's users of four different models of speech processors. For the electroacoustic evaluation, we used the Audioscan Verifit device with the HA-1 coupler and the listening check devices corresponding to each speech processor model. In cases where the transparency was not achieved, a modification was made in the frequency modulation gain adjustment and we used the Brazilian version of the “Phrases in Noise Test” to evaluate the speech perception in competitive noise. ResultsIt was observed that there was transparency between the frequency modulation system and the cochlear implant in 85% of the participants evaluated. After adjusting the gain of the frequency modulation receiver in the other participants, the devices showed transparency when the electroacoustic verification test was repeated. It was also observed that patients demonstrated better performance in speech perception in noise after a new adjustment, that is, in these cases; the electroacoustic transparency caused behavioral transparency. ConclusionThe electroacoustic evaluation protocol suggested was effective in evaluation of transparency between the frequency modulation system and the cochlear implant. Performing the adjustment of the speech processor and the frequency modulation system gain are essential when fitting this device.

Speech perception in noise is an important aspect of the rehabilitation of children with hearing loss. We aimed to evaluate the feasibility and reliability of the Dutch digits-in-noise (DIN) test in the clinical follow-up of children with hearing aids (HAs) and/or cochlear implants (CIs). A second aim of the study was to gain insight in the speech perception in noise performance of children with different degrees of hearing loss. We retrospectively analyzed DIN test data of Dutch-speaking children with hearing loss (N = 188; 5 to 18 years old). A free-field version of the DIN-test was used. Children with open-set phoneme recognition in quiet of >70% at 65 dB SPL (best aided condition) were included. Ages ranged from 5 to 18 years old. All were experienced HA or CI users and had used their device(s) for at least 1 year before the measurement in the study. The DIN-test was performed in the framework of a clinical rehabilitation program. During testing, children wore their own devices with normal daily programs. The average speech reception threshold (SRT) was -3.6 dB (SD 3.6) for the first list and significantly improved to -4.0 dB (SD 3.1) for the second list. HA users had a 4-dB better SRT compared with CI users. The larger the child's hearing loss, the worse the SRT is. However, 15% of the children who completed a first list of 24 trials were unable to complete a second list. Mean adaptive staircase trajectories across trials suggested that learning occurred throughout the first list, and that loss of sustained attention contributed to response variability during the second list. The DIN test can be used to assess speech perception in noise abilities for children with different degrees of hearing loss and using HAs or CIs. The children with hearing loss required a higher signal-to-noise ratio (SNR) than did normal-hearing children and the required SNR is larger as the hearing loss increases. However, the current measurement procedure should be optimized for use in standard pediatric audiological care, as 15% of the children were unable to conduct a second list after the first list to reach a more stable SNR.

Cochlear implantation is rapidly gaining acceptance as the most effective treatment for adult patients with unilateral deafness. The benefits for the pediatric population remain to be investigated. This study aimed to investigate the implications of cochlear implantation in children with congenital and noncongenital unilateral deafness. Four children, three with congenital and one with a sudden unilateral deafness, were studied after implantation. The children were aged 17 months, 4.5 years, 6.8 years, and 9 years at the time of implantation. Speech perception in noise and sound localization ability were evaluated using age-appropriate materials. The child with postlingual unilateral deafness rapidly integrated the normal acoustic hearing with the electrical signal from the cochlear implant and showed binaural benefits, as indicated by the localization ability and the improvement of speech perception in noise scores. The younger child with congenital unilateral deafness showed some clinical evidence of binaural integration and the two older children with congenital deafness have not yet indicated signs of binaural benefits. It seems that cochlear implantation in children with congenital unilateral deafness may provide some of the benefits of binaural hearing if implantation occurs within the critical period for bilateral auditory development.

Cochlear implant (CI) users have been shown to benefit from residual low-frequency hearing, specifically in pitch related tasks. It remains unclear whether this benefit is dependent on fundamental frequency (F0) or other acoustic cues. Three experiments were conducted to determine the role of F0, as well as its frequency modulated (FM) and amplitude modulated (AM) components, in speech recognition with a competing voice. In simulated CI listeners, the signal-to-noise ratio was varied to estimate the 50% correct response. Simulation results showed that the F0 cue contributes to a significant proportion of the benefit seen with combined acoustic and electric hearing, and additionally that this benefit is due to the FM rather than the AM component. In actual CI users, sentence recognition scores were collected with either the full F0 cue containing both the FM and AM components or the 500-Hz low-pass speech cue containing the F0 and additional harmonics. The F0 cue provided a benefit similar to the low-pass cue for speech in noise, but not in quiet. Poorer CI users benefited more from the F0 cue than better users. These findings suggest that F0 is critical to improving speech perception in noise in combined acoustic and electric hearing.

The aim of the study was to assess the effect of short-term musical training on speech perception in noise. In the present study speech perception in noise was measured pre- and post- short-term musical training. The musical training involved auditory perceptual training for raga identification of two Carnatic ragas. The training was given for eight sessions. A total of 18 normal hearing adults in the age range of 18-25 years participated in the study wherein group 1 consisted of ten individuals who underwent musical training and group 2 consisted of eight individuals who did not undergo any training. Results revealed that post training, speech perception in noise improved significantly in group 1, whereas group 2 did not show any changes in speech perception scores. Thus, short-term musical training shows an enhancement of speech perception in the presence of noise. However, generalization and long-term maintenance of these benefits needs to be evaluated.

Intervention for a Child with Auditory Neuropathy/Dys-synchrony

Temporal fine structure (TFS) sensitivity, frequency selectivity, and speech reception in noise were measured for young normal-hearing (NHY), old normal-hearing (NHO), and hearing-impaired (HI) subjects. Two measures of TFS sensitivity were used: the "TFS-LF test" (interaural phase difference discrimination) and the "TFS2 test" (discrimination of harmonic and frequency-shifted tones). These measures were not significantly correlated with frequency selectivity (after partialing out the effect of audiometric threshold), suggesting that insensitivity to TFS cannot be wholly explained by a broadening of auditory filters. The results of the two tests of TFS sensitivity were significantly but modestly correlated, suggesting that performance of the tests may be partly influenced by different factors. The NHO group performed significantly more poorly than the NHY group for both measures of TFS sensitivity, but not frequency selectivity, suggesting that TFS sensitivity declines with age in the absence of elevated audiometric thresholds or broadened auditory filters. When the effect of mean audiometric threshold was partialed out, speech reception thresholds in modulated noise were correlated with TFS2 scores, but not measures of frequency selectivity or TFS-LF test scores, suggesting that a reduction in sensitivity to TFS can partly account for the speech perception difficulties experienced by hearing-impaired subjects.

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.