Recognition In Quiet Research Articles

Evaluation of the Optimized Pitch and Language Strategy in Cochlear Implant Recipients.

The Optimized Pitch and Language (OPAL) strategy enhances pitch perception through coding of fundamental frequency (F0) amplitude modulation information in the stimulus envelope delivered to a cochlear implant. Previous research using a prototype of the strategy demonstrated significant benefits in musical pitch and lexical tone discrimination tasks with no degradation in speech recognition when compared with the clinical Advanced Combination Encoder (ACE) strategy in a small group of subjects. Based on those studies, a modified version of the strategy was implemented in the commercial Nucleus CP900 series processor. The aims of the present study were to establish whether the CP900 OPAL implementation continued to provide improved F0 pitch perception in a speech intonation task with no degradation to speech perception in quiet and noise, when compared with the clinical ACE strategy in a larger cohort of subjects. Further aims were to evaluate fitting procedures and subject acclimatization to the strategy after take-home experience. Twenty experienced adult cochlear implant recipients were enrolled in the study. Two subjects withdrew during the study leaving 18 sets of data for analysis. A repeated-measures single-subject design with take-home experience was used to test for improved speech intonation perception using OPAL compared with ACE and for comparable performance between strategies for open-set word recognition in quiet at two presentation levels, sentence recognition in adaptive 4-talker babble noise, and speech intelligibility ratings. The stimulation rate employed for OPAL was 1200 pulses per second/channel which was higher than the default clinical rate of 900 pulses per second/channel used for ACE by all subjects in the present study. Two variations of the OPAL "F0 restore gain" (the gain applied to restore the loudness of modulated channels) were investigated: "custom" measured per subject and "default" which was the average of all subject custom gains. A significant group mean benefit on the intonation test of 8.5% points was shown for OPAL compared with ACE. There was a significant period of adaptation to OPAL with significantly poorer sentence in noise scores acutely and after only 2 weeks of take-home experience. After 4 weeks of take-home experience, comparable word perception in quiet and sentence perception in noise for OPAL were obtained. Furthermore, there was good subject acceptability in the field with comparable speech intelligibility ratings between strategies. Results of the fitting procedure showed that OPAL did not require any additional steps compared with fitting of ACE. A default F0 restore gain provided comparable outcomes to a custom gain setting. The CP900 OPAL implementation provided a significant benefit to perception of speech intonation when compared with ACE. Comparable speech perception (in quiet and noise) and subjective ratings of speech intelligibility between strategies were also achieved after a period of acclimatization. These outcomes are consistent with results of earlier studies using prototype versions of the strategy and reaffirm its potential for improvement of F0 pitch perception in speech while preserving coding of segmental speech information. Furthermore, the OPAL strategy can be programmed into subject's processors using the same fitting procedures used for ACE thereby simplifying its adoption in clinical settings.

Pediatric Hearing Loss and Speech Recognition in Quiet and in Different Types of Background Noise.

Purpose Speech recognition deteriorates with hearing loss, particularly in fluctuating background noise. This study examined how hearing loss affects speech recognition in different types of noise to clarify how characteristics of the noise interact with the benefits listeners receive when listening in fluctuating compared to steady-state noise. Method Speech reception thresholds were measured for a closed set of spondee words in children (ages 5-17 years) in quiet, speech-spectrum noise, 2-talker babble, and instrumental music. Twenty children with normal hearing and 43 children with hearing loss participated; children with hearing loss were subdivided into groups with cochlear implant (18 children) and hearing aid (25 children) groups. A cohort of adults with normal hearing was included for comparison. Results Hearing loss had a large effect on speech recognition for each condition, but the effect of hearing loss was largest in 2-talker babble and smallest in speech-spectrum noise. Children with normal hearing had better speech recognition in 2-talker babble than in speech-spectrum noise, whereas children with hearing loss had worse recognition in 2-talker babble than in speech-spectrum noise. Almost all subjects had better speech recognition in instrumental music compared to speech-spectrum noise, but with less of a difference observed for children with hearing loss. Conclusions Speech recognition is more sensitive to the effects of hearing loss when measured in fluctuating compared to steady-state noise. Speech recognition measured in fluctuating noise depends on an interaction of hearing loss with characteristics of the background noise; specifically, children with hearing loss were able to derive a substantial benefit for listening in fluctuating noise when measured in instrumental music compared to 2-talker babble.

Influence of speaking style adaptations and semantic context on the time course of word recognition in quiet and in noise

This study examines the effects of different listener-oriented speaking styles and semantic contexts on online spoken word recognition using eyetracking. In Experiment 1, different groups of listeners participated in a word-identification-in-noise and in a pleasantness-rating task. Listeners heard sentences with high- versus low-predictability semantic contexts produced in infant-directed speech, Clear Speech, and Conversational Speech. Experiment 2 (in silence) and 3 (in noise) investigated the time course of visual fixations to target objects when participants were listening to different speaking styles and contexts. Results from all experiments show that relative to conversational speech, both infant-directed speech and Clear Speech improved word recognition for high-predictability sentences, in quiet as well as in noise. This indicates that established advantages of infant-directed speech for young listeners cannot be attributed only to affect; the acoustic enhancements in infant-directed speech benefit adult speech processing as well. Furthermore, in silence (Experiment 2) lexical access was facilitated by contextual cues even in conversational speech; but in noise (Experiment 3) listeners reliably focused the target only when a combination of contextual cues and listener-adapted acoustic–phonetic cues were available. These findings suggest that both semantic cues and listener-oriented acoustic enhancements are needed to facilitate word recognition, especially in adverse listening conditions.

Controlled comparative clinical trial of hearing benefit outcomes for users of the Cochlear™ Nucleus® 7 Sound Processor with mobile connectivity

Objectives: To assess subjective benefits and objective speech recognition performance following a take-home trial with the new Cochlear™ Nucleus® 7 Sound Processor (SP), in experienced users of compatible cochlear implants from Cochlear Limited.Methods: A total of 37 adult participants were fitted with the Nucleus 7 SP and used the device for up to one year. Baseline speech recognition was assessed at the initial fitting session, using each participant’s own SP, and Client Oriented Scale of Improvement (COSI) goals were identified. Speech recognition was measured after 3 months of device use and outcomes of the COSI and a non-validated Processor Comparison Questionnaire (PCQ) were collected. After 11 months, a subset of subjects were tested on speech recognition delivered via direct wireless streaming from an Apple® smartphone to the SP and compatible hearing aid on the opposite side (if worn).Results: The COSI and PCQ instruments both indicated significant improvement in perceived subjective benefits in comparison to the participants’ previous SPs. Direct streaming via an Apple mobile phone showed improvements when compared with the acoustic alone condition. Standard speech recognition in quiet and noise was equivalent to that obtained using a previous generation SP which uses the same basic processing as the Nucleus 7 Sound Processor.Conclusions: The incremental refinements provided by the Nucleus 7 Sound Processor provide real-world benefits in key areas such as upgraded wireless connectivity. The COSI proved to be an effective tool for individualized assessment of specific benefits that may not be addressed by more standardized instruments.

Temporal Sensitivity Measured Shortly After Cochlear Implantation Predicts 6-Month Speech Recognition Outcome.

Psychoacoustic tests assessed shortly after cochlear implantation are useful predictors of the rehabilitative speech outcome. While largely independent, both spectral and temporal resolution tests are important to provide an accurate prediction of speech recognition. However, rapid tests of temporal sensitivity are currently lacking. Here, we propose a simple amplitude modulation rate discrimination (AMRD) paradigm that is validated by predicting future speech recognition in adult cochlear implant (CI) patients. In 34 newly implanted patients, we used an adaptive AMRD paradigm, where broadband noise was modulated at the speech-relevant rate of ~4 Hz. In a longitudinal study, speech recognition in quiet was assessed using the closed-set Freiburger number test shortly after cochlear implantation (t0) as well as the open-set Freiburger monosyllabic word test 6 months later (t6). Both AMRD thresholds at t0 (r = -0.51) and speech recognition scores at t0 (r = 0.56) predicted speech recognition scores at t6. However, AMRD and speech recognition at t0 were uncorrelated, suggesting that those measures capture partially distinct perceptual abilities. A multiple regression model predicting 6-month speech recognition outcome with deafness duration and speech recognition at t0 improved from adjusted R = 0.30 to adjusted R = 0.44 when AMRD threshold was added as a predictor. These findings identify AMRD thresholds as a reliable, nonredundant predictor above and beyond established speech tests for CI outcome. This AMRD test could potentially be developed into a rapid clinical temporal-resolution test to be integrated into the postoperative test battery to improve the reliability of speech outcome prognosis.

Reliability of Measures Intended to Assess Threshold-Independent Hearing Disorders.

Recent animal studies have shown that noise exposure can cause cochlear synaptopathy without permanent threshold shift. Because the noise exposure preferentially damaged auditory nerve fibers that processed suprathreshold sounds (low-spontaneous rate fibers), it has been suggested that synaptopathy may underlie suprathreshold hearing deficits in humans. Recently, several researchers have suggested measures to identify the pathology or pathologies underlying suprathreshold hearing deficits in humans based on results from animal studies; however, the reliability of some of these measures have not been assessed. The purpose of this study was to assess the test-retest reliability of measures that may have the potential to relate suprathreshold hearing deficits to site(s)-of-lesion along the peripheral auditory system in humans. Adults with audiometric normal hearing were tested on a battery of behavioral and physiologic measures that included (1) thresholds in quiet (TIQ), (2) thresholds in noise (TIN), (3) frequency-modulation detection threshold (FMDT), (4) word recognition in four listening conditions, (5) distortion-product otoacoustic emissions (DPOAE), (6) middle ear muscle reflex (MEMR), (7) tone burst-elicited auditory brainstem response (tbABR), and (8) speech-evoked ABR (sABR). Data collection for each measure was repeated over two visits separated by at least one week. The residuals of the correlation between the suprathreshold measures and TIQ serve as functional and quantitative proxies for threshold-independent hearing disorders because they represent the portion of the raw measures that is not dependent on TIQ. Reliability of the residual measures was assessed using intraclass correlation (ICC). Reliability for the residual measures was good (ICC ≥ 0.75) for FMDT, DPOAEs, and MEMR. Residual measures showing moderate reliability (0.5 ≤ ICC < 0.75) were tbABR wave I amplitude, TIN, and word recognition in quiet, noise, and time-compressed speech with reverberation. Wave V of the tbABR, waves of the sABR, and recognition of time-compressed words had poor test-retest reliability (ICC < 0.5). Reliability of residual measures was mixed, suggesting that care should be taken when selecting measures for diagnostic tests of threshold-independent hearing disorders. Quantifying hidden hearing loss as the variance in suprathreshold measures of auditory function that is not due to TIQ may provide a reliable estimate of threshold-independent hearing disorders in humans.

Relative contributions of auditory and cognitive functions on speech recognition in quiet and in noise among older adults

IntroductionHearing acuity, central auditory processing and cognition contribute to the speech recognition difficulty experienced by older adults. Therefore, quantifying the contribution of these factors on speech recognition problem is important in order to formulate a holistic and effective rehabilitation. ObjectiveTo examine the relative contributions of auditory functioning and cognition status to speech recognition in quiet and in noise. MethodsWe measured speech recognition in quiet and in composite noise using the Malay Hearing in noise test on 72 native Malay speakers (60–82 years) older adults with normal to mild hearing loss. Auditory function included pure tone audiogram, gaps-in-noise, and dichotic digit tests. Cognitive function was assessed using the Malay Montreal cognitive assessment. ResultsLinear regression analyses using backward elimination technique revealed that had the better ear four frequency average (0.5–4kHz) (4FA), high frequency average and Malay Montreal cognitive assessment attributed to speech perception in quiet (total r2=0.499). On the other hand, high frequency average, Malay Montreal cognitive assessment and dichotic digit tests contributed significantly to speech recognition in noise (total r2=0.307). Whereas the better ear high frequency average primarily measured the speech recognition in quiet, the speech recognition in noise was mainly measured by cognitive function. ConclusionsThese findings highlight the fact that besides hearing sensitivity, cognition plays an important role in speech recognition ability among older adults, especially in noisy environments. Therefore, in addition to hearing aids, rehabilitation, which trains cognition, may have a role in improving speech recognition in noise ability of older adults.

Neurocognitive Factors Contributing to Cochlear Implant Candidacy

Clinical adult cochlear implant (CI) candidacy evaluations rely heavily on measures of sentence recognition under the best-aided listening conditions. The hypothesis tested in this study was that nonauditory measures of neurocognitive processes would contribute to scores on preoperative sentence recognition for CI candidates, above and beyond hearing ability as assessed using pure-tone average (PTA). Support for this hypothesis would suggest that best-aided sentence recognition is not simply a measure of hearing ability; rather, neurocognitive functions contribute to performance and should be considered while counseling patients during CI candidacy evaluation about postoperative rehabilitative and outcome expectations. Neurocognitive functions, such as working memory capacity, inhibition-concentration, information processing speed, and nonverbal reasoning contribute to aided speech recognition outcomes in adults with hearing loss. This study examined the roles of these neurocognitive factors on preoperative speech recognition performance in adults evaluated for CI candidacy. Thirty-one postlingually deafened adult CI candidates were enrolled. Participants were assessed using nonauditory measures of working memory capacity, inhibition-concentration, information processing speed, and nonverbal reasoning. Measures of sentence recognition in quiet and in multitalker babble (AzBio sentences) as well as sentences from the City University of New York in quiet were collected under best-aided conditions. AzBio sentence recognition scores in babble were predicted significantly by scores of working memory capacity after accounting for PTA. Similarly, the City University of New York sentence recognition scores were predicted significantly by nonverbal reasoning after accounting for PTA. Findings support the idea that clinical measures of sentence recognition may be affected to varying degrees by neurocognitive functions, and these functions should be considered during evaluation for CI candidacy.

Audiological and clinical outcomes of a transcutaneous bone conduction hearing implant: Six-month results from a multicentre study.

To compare the hearing performance of patients with conductive and mild mixed hearing loss and single-sided sensorineural deafness provided with a new transcutaneous bone conduction hearing implant (the Baha Attract System) with unaided hearing as well as aided with a sound processor on a softband. Furthermore, to evaluate safety and subjective benefit before and after implantation of the test device. Fifty-four adult patients in five participating centres were enrolled in this prospective study. Baseline data were collected during a pre-operative visit, and after a softband trial, all patients were implanted unilaterally. Follow-up visits were scheduled at 10days, 4, 6, 12weeks and 6months. Free-field hearing thresholds pure-tone average (PTA4 in dB HL; mean threshold at 500, 1000, 2000, 4000Hz; primary outcome measure). Individual free-field hearing thresholds, speech recognition in quiet and in noise, soft tissue status during follow-up and subjective benefit as measured with the Abbreviated Profile of Hearing Aid Benefit (APHAB), Speech, Spatial and Qualities of Hearing Scale (SSQ) and Health Utilities Index (HUI) questionnaires. Implantation of the Baha Attract System resulted in favourable audiological outcomes compared to unaided conditions. On the primary outcome parameter, a statistically significant improvement was observed compared to unaided hearing for the patients with conductive/mixed hearing loss (mean PTA4 difference -20.8dB HL, SD 9.8; P<0.0001) and for the patients with single-sided sensorineural deafness (SSD) (mean PTA4 difference -21.6dB HL, SD 12.2; P<0.0001). During all audiology tests, the non-test ear was blocked. Statistically significant improvements were also recorded in speech tests in quiet and noise compared to unaided hearing for the conductive/mixed hearing loss group and for speech in quiet in the SSD group. Compared to the pre-operative measurement with softband, no significant differences were recorded in the PTA4 free-field hearing threshold or the other audiological outcomes in either of the groups (P>0.05). Soft tissue-related issues observed during follow-up included numbness, pain/discomfort at the implant site and to a lesser extent pressure-related skin complications. A declining trend was noted in the rate of these complications during follow-up. Approximately 20% of patients reported some degree of numbness and 38% (slight) pain/discomfort at final follow-up of 6months. Good results on the subjective benefit questionnaires were observed, with statistically significant improvements on APHAB and SSQ questionnaires, and on the hearing attribute of HUI3. The Baha Attract System provided a significant improvement in hearing performance and subjective benefit compared to the pre-operative unaided condition (with the non-test ear blocked). Hearing performance of the Baha Attract was similar to a test situation with the same sound processor on a softband. A proportion of the patients reported numbness and pain/discomfort at the implant site during follow-up, especially during the first post-operative weeks. Based on the results of the current multicentre study, the Baha Attract can be considered as a treatment option for patients with the aforementioned hearing losses. Especially in the SSD patients, a careful selection procedure is warranted. Therefore, a pre-operative trial should be part of the decision-making process before fitting a patient with the Baha Attract System.

A preliminary study on time-compressed speech recognition in noise among teenage students who use personal listening devices

Objective: To compare speech perception obtained with different time compression rates in teenagers that do or do not use personal listening devices (PLDs).Design: Teenagers in a high school were recruited to complete questionnaires reporting their recreational noise exposure using PLDs. The dose of individual recreational noise exposure was calculated. The individuals with the most and least doses of recreational noise were selected and grouped into PLD users and non-PLD users. Normal rate and time-compressed (60% and 70%) speech recognition in quiet and noisy conditions was measured.Study sample: PLD user and non-PLD user group each included 20 participants.Results: ANOVA analysis showed that the effect of group, background, compression rate, and interactions between any two factors are significant. Post hoc analysis showed that the speech recognition scores with normal rate in quiet and noise and those obtained from time-compressed speech in the quiet condition were not significantly different between PLD users and non-PLD users. However, differences in the time-compressed speech recognition scores (60% and 70%) in noisy conditions between the two groups were statistically significant.Conclusions: The fast-speed speech recognition in noise decreased significantly in PLD users compared with that in non-PLD users selected by extreme entertainment exposure.

Sentence Recognition in Quiet and Noise in School-Going Indian Children Using Bimodal Hearing.

To compare sentence recognition scores in quiet and noise in 8 to 15-years old children using bimodal hearing in CI only condition and bimodal condition (BM) (CI + HA). Twenty prelingually deafened participants (8-15years) using cochlear implant in one ear and hearing aid in the other ear were recruited. The sentence recognition was assessed in CI Quiet, CI + 15dB SNR, CI + 8dB SNR, BM Quiet, BM + 15dB SNR and BM + 8dB SNR. The highest sentence recognition scores were obtained in the quiet condition, followed by the + 15dB SNR and then by the + 8dB SNR condition in both CI only and BM conditions. The sentence recognition scores obtained in BM condition were significantly better than CI only condition. Variables like unaided PTA and aided PTA correlated significantly with the sentence recognition scores in BM conditions. This study was done on Indian population where till date no published data is available. It recommends that all the school going children using unilateral cochlear implants should be recommended to use a hearing aid in the contra lateral ear. This practice will help them to receive all the binaural benefits, better listening in noise, localization, spatial release from masking and pitch perception in comparison to unilateral CI use. Moreover, it will help to keep the auditory nerve viable for future implantation which is an important implication for children who have limited benefit from the contra lateral hearing aid.

How to Optimally Fit a Hearing Aid for Bimodal Cochlear Implant Users: A Systematic Review.

Bimodal hearing has shown to improve speech recognition in quiet and in noise and to improve sound localization compared with unilateral cochlear implant (CI) use alone. Fitting the CI and hearing aid (HA) separately has been described well, but HA fitting procedures for bimodal CI users are not well researched or widely accepted. The aim of the present study was to systematically review the literature on the effect of different HA fitting strategies on auditory performance in bimodal CI users. Original articles, written in English, were identified through systematic searches in Medline (OvidSP), Embase, Web of Science, Scopus, CINAHL, Cochrane, PubMed publisher, and Google Scholar. The quality of the studies was assessed on five aspects: methodologic quality (with the methodological index for nonrandomized studies score), number of subjects, quality of the description of contralateral hearing loss, quality of HA verification, and direct comparison of HA fitting procedures based on auditory performance. A total of 1665 records were retrieved, of which 17 were included for systematical reviews. Critical appraisal led to three high-quality studies, 10 medium-quality studies, and four low-quality studies. The results of the studies were structured according to four topics: frequency response, frequency translation/transposition, dynamic range compression, and loudness. In general, a bimodal benefit was found in most studies, using various strategies for the HA fitting. Using a standard prescription rule such as National Acoustics Laboratory formula-non-linear 1, National Acoustics Laboratory formula-non-linear 2, or desired sensation level is a good starting point in children and adults. Although a bimodal benefit was found in most studies, there is no clear evidence how certain choices in HA fitting contribute to optimal bimodal performance. A generally accepted HA prescription rule is an essential part of most fitting procedures used in the studies. Current evidence suggests that frequency lowering or transposition is not beneficial. Individual fine tuning based on loudness or general preference is often applied, but its additional value for auditory performance should be investigated more thoroughly. Good quality comparative studies are needed to further develop evidence-based fitting procedures in case of bimodal listening.

Ins, Outs of Frequency-lowering Processing

Ins, Outs of Frequency-lowering Processing

Assessment of speech recognition abilities in quiet and in noise: a comparison between self-administered home testing and testing in the clinic for adult cochlear implant users

Self speech recognition tests in quiet and noise at home are compared to the standard tests performed in the clinic. Potential effects of stimuli presentation modes (loudspeaker or audio cable) and assessment (clinician or self-assessment at home) on test results were investigated. Speech recognition in quiet was assessed using the standard Dutch test with monosyllabic words. Speech recognition in noise was assessed with the digits-in-noise test. Sixteen experienced CI users (aged between 44 and 83 years) participated. No significant difference was observed in speech recognition in quiet between and presentation modes. Speech recognition in noise was significantly better with the audio cable than with the loudspeaker. There was no significant difference in speech recognition in quiet at 65 dB and in speech recognition in noise between self-assessment at home and testing in the clinic. At 55 dB, speech recognition assessed at home was slightly but significantly better than that assessed in the clinic. The results demonstrate that it is feasible for experienced CI users to perform self-administered speech recognition tests at home. Self-assessment by CI users of speech recognition in quiet and noise within the home environment could serve as an alternative to the tests performed in the clinic.

Beyond Sentence Recognition in Quiet for Older Adults: Implications for Cochlear Implant Candidacy.

To study postoperative hearing outcomes in older adult cochlear implant recipients who did not meet Medicare candidacy criteria by sentence testing in quiet. Case Control Series. University Based Tertiary Referral Cochlear Implant Center. Fifty-four patients age 60 or greater with bilateral moderate to profound sensorineural hearing loss who underwent cochlear implantation. Patients were divided into three groups by preoperative testing scores: 1) sentence recognition in quiet and monosyllabic word recognition scores ≤40%, 2) sentence recognition in quiet scores >40% and sentence recognition in noise scores ≤40%, and 3) sentence recognition in quiet scores >40% and monosyllabic word recognition scores ≤40% in the ear to be implanted. Cochlear implantation. Pre- versus postoperative sentence and word recognition scores. All three groups received a statistically significant benefit from their cochlear implant as measured by both postoperative sentence and word recognition. When comparing postoperative sentence recognition scores between groups, there were no statistically significant differences (Group 1: mean 83.1%, SD ± 17.4%; Group 2: mean 90.1%, SD ± 8.0%; Group 3: mean 90.6%, SD ± 6.9%). When comparing postoperative monosyllabic word recognition scores, there were no statistically significant differences between groups (Group 1: mean 60.3%, SD ± 19.6%; Group 2: mean 66.8%, SD ± 20.0%; Group 3: mean 70.0%, SD ± 18.8%). Results of this study demonstrate that older patients who do not meet current Medicare candidacy criteria derive significant long-term benefit from cochlear implantation when either sentence in noise or monosyllabic word recognition in quiet ≤40% is used to determine candidacy. Further research and greater numbers are needed to better characterize the role of monosyllabic word recognition in cochlear implant candidacy.

KORZYŚCI Z AKTUALIZACJI PROCESORA AUDIO U DOŚWIADCZONYCH UŻYTKOWNIKÓW AKTYWNEGO IMPLANTU UCHA ŚRODKOWEGO: ROZUMIENIE MOWY W HAŁASIE I SUBIEKTYWNA OCENA

BackgroundMicrophone directionality plays an important role in speech understanding in challenging acoustic environments. A new audio processor (AP) from Med-El, known as Samba, automatically detects and selects optimal settings depending on the listening situation. This clinical investigation evaluated speech understanding in noise and subjective benefit of an AP upgrade from the prior Amadé to the new Samba.Material and MethodsFourteen Vibrant Soundbridge users with at least 3 months experience with the Amadé AP received the new Samba AP. Speech recognition in quiet was measured using the Freiburger monosyllable test. Speech understanding in noise was assessed using the Oldenburger sentence test. Subjective benefit was determined with the Hearing Device Satisfaction Scale and the Abbreviated Profile of Hearing Aid Benefit.ResultsNo differences were detected in pure tone audiometry or speech recognition in quiet between the two audio processors. However, the new Samba AP performed significantly better in challenging noise situations: when speech came from the front and noise from the back, the signal-to-noise ratio (SNR) improved by 3.4 dB with the automatic mode of the Samba AP compared to the Amadé AP. When the sources of speech and noise were switched, a significant improvement of 1.8 dB SNR was observed. Based on the two questionnaires, subjective benefit in daily life and device satisfaction were comparable for the two APs.ConclusionsDue to its new features, the Samba AP gave significantly better results in challenging acoustical test situations. Even when the direction of background noise changed, the Samba AP performed better due to the new built-in adaptive directional microphones.

Spoken word recognition in noise in Mandarin-speaking pediatric cochlear implant users

ObjectiveThe purpose of the present study was to compare spoken word recognition performance in the presence of speech spectrum-shaped noise and four-talker babbles in Mandarin-speaking children with cochlear implants (CIs). MethodsParticipants included 33 children with unilateral CIs (with a mean age of 10.4 ± 2.9 years old and a mean length of CI use of 7.5 ± 3.0 years). The Standard Chinese version of Lexical Neighborhood Test was implemented in quiet, speech-spectrum-shaped noise (SSN), and four-talker babble (FTB). The signal-to-noise ratios (SNRs) were set at +5 and + 10 dB for both types of maskers. Participants responded by verbally repeating each word they heard and the response was scored as the percentage accuracy of recognition performance. A Generalized Linear Model (GLM) fitting, correlational tests, and a two-way repeated-measures ANOVA were conducted on the percent-correct data. ResultsWord recognition in quiet was on average 74.5% correct but dropped to 57.3% and 48.8% correct for SSN and FTB at 10 dB SNR, respectively, and 44.4% and 32.6% correct for SSN and FTB at 5 dB SNR, respectively. In both quiet and noise conditions, the participants showed lower recognition accuracy for the hard words than for the easy words. Disyllabic words were recognized with higher accuracy rates than were the monosyllabic words. The GLM analysis revealed that all four tested factors (masker type, SNR, lexical neighborhood feature, and lexical type) showed significant impacts on word recognition in children with CIs. Word recognition scores in the two types of maskers were significantly correlated for the disyllabic words at both SNRs and monosyllabic words at 10 dB SNR. ConclusionsThe present study demonstrated that the lexical features such as the lexical neighborhood characteristics and lexical type had significant effects on speech recognition performance in both quiet and noise conditions in pediatric CI users. Children with years of experience of CI use still encountered remarkable difficulties in everyday listening environment although their speech recognition in quiet reached relatively desired level. Fluctuating noise, such as speech babbles, caused greater challenge than steady-state noise for speech recognition in children with CIs.

Backward masking of tones and speech in people who do and do not stutter

PurposeThere is evidence of an auditory-perceptual component of stuttering, and backward masking (BM) is a task to explore that role. Prior research reported poorer thresholds for BM tones in a group of children who persisted in stuttering compared to those for a group that did not persist. This study examined BM for adults who stutter for tones and for speech, which tests a phonetic aspect of hearing. MethodEight persons who stutter (PWS) were closely matched with eight controls (PNS) in terms of phonological abilities, verbal span tasks, age, sex and non-verbal intelligence. These participants were examined for their ability to recognize vowel-consonant (VC) speech syllables and tones in BM paradigm with 0 ms and 300 ms masker to signal onset conditions. ResultsPWS showed significantly poorer performance for speech syllable recognition in quiet and in conditions with masking noise. The pattern of speech errors was similar in both groups, but the PWS produced more errors. A significant condition by group interaction in backward masking for tones was attributed to higher masked thresholds in PWS than in PNS in the 0 ms delay condition for BM for tones. ConclusionThis was the first study to examine BM for speech in PWS. Results provide support for a small auditory-perceptual deficit for speech understanding in adults who stutter that was revealed in the absence of a lexical context. The speech results are explained in terms of possible indistinct phoneme boundaries in PWS and the effects of vowel context in speech recognition.

Verbal Learning and Memory After Cochlear Implantation in Postlingually Deaf Adults: Some New Findings with the CVLT-II.

Despite the importance of verbal learning and memory in speech and language processing, this domain of cognitive functioning has been virtually ignored in clinical studies of hearing loss and cochlear implants in both adults and children. In this article, we report the results of two studies that used a newly developed visually based version of the California Verbal Learning Test-Second Edition (CVLT-II), a well-known normed neuropsychological measure of verbal learning and memory. The first study established the validity and feasibility of a computer-controlled visual version of the CVLT-II, which eliminates the effects of audibility of spoken stimuli, in groups of young normal-hearing and older normal-hearing (ONH) adults. A second study was then carried out using the visual CVLT-II format with a group of older postlingually deaf experienced cochlear implant (ECI) users (N = 25) and a group of ONH controls (N = 25) who were matched to ECI users for age, socioeconomic status, and nonverbal IQ. In addition to the visual CVLT-II, subjects provided data on demographics, hearing history, nonverbal IQ, reading fluency, vocabulary, and short-term memory span for visually presented digits. ECI participants were also tested for speech recognition in quiet. The ECI and ONH groups did not differ on most measures of verbal learning and memory obtained with the visual CVLT-II, but deficits were identified in ECI participants that were related to recency recall, the buildup of proactive interference, and retrieval-induced forgetting. Within the ECI group, nonverbal fluid IQ, reading fluency, and resistance to the buildup of proactive interference from the CVLT-II consistently predicted better speech recognition outcomes. Results from this study suggest that several underlying foundational neurocognitive abilities are related to core speech perception outcomes after implantation in older adults. Implications of these findings for explaining individual differences and variability and predicting speech recognition outcomes after implantation are discussed.

Cochlear Implantation in Adults With Asymmetric Hearing Loss: Speech Recognition in Quiet and in Noise, and Health Related Quality of Life.

To examine the possible speech recognition and health related quality of life (HRQoL) benefits of cochlear implantation among adults with asymmetric sensorineural hearing loss. Retrospective chart review, single-subject design. A total of 45 adult cochlear implant recipients with asymmetric sensorineural hearing loss where performance for the best-aided condition exceeded 60% correct open set sentence recognition in quiet, and the implanted ear met traditional candidacy criteria. End point testing of the implanted ear was evaluated with use of the Consonant-Vowel Nucleus-Consonant (CNC) word test and AzBio sentence test materials in quiet, and bimodally with the AzBio sentence test materials in noise at +5 dB signal-to-noise ratio (SNR). HRQoL was measured using the Nijmegen Cochlear Implant Questionnaire (NCIQ). Measured in quiet, with the non-implanted ear plugged, the average CNC word scores increased from 9.1% preoperatively to 55.7% (p < 0.01) at the 6-month post-activation test interval. Similarly, average AzBio sentence scores in quiet, with the non-implanted ear plugged, increased from 13.9% preoperatively to 73.4% (p < 0.01) at the 6-month post-activation test interval. Finally, in the bilateral/bimodal condition, the AzBio sentence score in +5 dB SNR improved from an average of 26.8% preoperatively to 52.4% (p < 0.01) at the 6-month test interval. Results of the NCIQ showed improved scores on all six subdomains. These data demonstrate significant benefit of cochlear implantation among a group of postlingually deafened adults whose preoperative hearing and aided speech recognition fell outside of the currently specified Food and Drug Administration candidacy guidelines. Results of this study support the evaluation of a candidate's speech recognition in noise in the best-aided condition to adequately assess candidacy for a cochlear implant.