Sentences In Quiet Research Articles

The Effects of Residual Hearing in Traditional Cochlear Implant Candidates After Implantation With a Conventional Electrode

To analyze the effects of residual hearing on postoperative speech performance in traditional cochlear implant (CI) patients implanted with a conventional electrode. Retrospective review. Academic tertiary referral center. A total of 129 adults implanted by a single surgeon at a tertiary care facility between June 2005 and November 2010 with measurable preoperative pure tone thresholds at any frequency were included. Cochlear implantation with a conventional electrode via an anterior inferior cochleostomy. Speech perception using monosyllabic word scores in quiet and sentences in quiet and noise in the electric (CI-only) condition of the implanted ear. Preservation of hearing was defined as complete for postoperative thresholds within 10 dB of preimplant values and partial if greater than 11 dB. Pure tone audiometry and speech perception testing were performed preoperatively and at regular intervals postoperatively, with the 1-year evaluation being the final outcome period. Preservation at any frequency or level was not a factor in speech perception outcome, although preservation was more common in low frequencies. Hearing preservation was correlated with younger age at implantation, but was not related to length of hearing loss, cause of deafness, device type, sex, preoperative speech performance, or low-frequency pure-tone average. Hearing can be preserved in traditional CI patients implanted with a conventional electrode. Although preservation of hearing may have implications for future technology, it is not currently correlated with speech performance in the CI-only condition.

Effects of Semantic and Acoustic Context on Nonword Detection in Children With Hearing Loss

Children with hearing loss (HL) are known to have smaller receptive vocabularies than children with normal hearing (NH). This may be due, in part, of their reduced exposure to new words and their slower rate of word learning. A necessary prerequisite to lexical development is the detection of new words in conversation. The purpose of this study was to examine the effects of HL on children's ability to detect the presence of nonwords within sentences that varied in semantic and acoustic context. Twenty-nine children with NH and 16 children with HL between the ages of 7 and 13 years participated. The children listened to short sentences and reported the number of nonwords detected, ranging from zero to two nonwords, in each sentence. The structure of the sentences was either meaningful or nonsensical to the children to reveal the effects of semantic context. The effects of acoustic context were revealed by presenting the sentences in quiet, steady-state noise, and in multi-talker babble. Significant effects of age (older > younger), hearing (NH > HL), and listening condition (quiet > noise and babble) were observed. Also, nonword detection was better for semantically meaningful sentences than for nonsense sentences. Error analyses revealed that the children with NH tended to underestimate the number of nonwords in meaningful sentences but not in nonsense sentences. The children with HL, however, were more likely to underestimate the number of nonwords than were the children with NH for both meaningful and nonsense sentences. These error patterns were observed in each listening condition. Error patterns suggest that children with HL apply strong repair strategies during speech perception, which may limit their opportunities to learn new words.

Cochlear Implantation in Patients Profoundly Deafened After Head Injury

There is very little information in the literature regarding outcomes of cochlear implantation in patients profoundly deafened after head injury. The aim of this study was to assess outcomes in this group of patients. Retrospective case review. The Manchester Cochlear Implant Programme, University of Manchester. Profoundly deafened patients after head injury who proceeded to cochlear implantation for auditory rehabilitation. Mean age and duration of deafness at implantation. Preimplantation and postimplantation speech perception outcomes were measured using Bench Kowel Bamford (BKB) sentences in quiet and noise, City University of New York sentences with lip reading and Arthur Boothroyd words scoring the percentage phonemes correct. Twenty patients received 23 cochlear implants. Mean age at implantation was 51 years (standard deviation, 12 yr). Mean duration of deafness at implantation was 12 years (range, 1-30 yr).Preimplantation BKB score in quiet of 0%. Mean postimplantation BKB score in quiet was 64% (range, 0%-100%) and in noise was 61% (range, 0%-97%). Three were nonusers, and 1 required reimplantation. There was a moderately negative correlation between outcome and age at implantation (r = -0.41, p < 0.05) and between outcome and duration of deafness (r = -0.52, p < 0.05). Cochlear implantation is an effective method for hearing rehabilitation in profoundly deafened patients after head injury. However, negative factors, such as significant injury to the central auditory pathway, basal turn obliteration, long duration of deafness, and nonauditory stimulation, should be considered in the preoperative assessment of these patients.

Cochlear implantation in older adults.

Cochlear implants allow individuals with severe to profound hearing loss access to sound and spoken language. The number of older adults in the United States who are potential candidates for cochlear implantation (CI) is approximately 150,000 and will continue to increase with the aging of the population. Should CI be routinely recommended for these older adults, and do these individuals benefit from CI? We reviewed our 12-year experience with CI in adults aged ≥60 years (n = 445) at Johns Hopkins Medical Institutions to investigate the impact of CI on speech understanding and to identify factors associated with speech performance. Complete data on speech outcomes at baseline and 1 year post-CI were available for 83 individuals. Our results demonstrate that CI in adults aged ≥60 years consistently improved speech understanding scores, with a mean increase of 60.0% (SD 24.1) on HINT (Hearing in Noise Test) sentences in quiet. The magnitude of the gain in speech scores was negatively associated with age at implantation, such that for every increasing year of age at CI the gain in speech scores was 1.3 percentage points less (95% confidence interval [95% CI], 0.6-1.9) after adjusting for age at hearing loss onset. Conversely, individuals with higher pre-CI speech scores (HINT scores between 40% and 60%) had significantly greater post-CI speech scores by a mean of 10.0 percentage points (95% CI, 0.4-19.6) than those with lower pre-CI speech scores (HINT <40%) after adjusting for age at CI and age at hearing loss onset. These results suggest that older adult CI candidates who are younger at implantation and with higher preoperative speech scores obtain the highest speech understanding scores after CI, with possible implications for current United States Medicare policy. Finally, we provide an extended discussion of the epidemiology and impact of hearing loss in older adults. Future research of CI in older adults should expand beyond simple speech outcomes to take into account the broad cognitive, social, and physical functioning outcomes that are likely detrimentally affected by hearing loss and may be mitigated by CI.

Recognition memory in noise for speech of varying intelligibility

Speech intelligibility is greatly affected by the presence of noise. However, there has been little research investigating the effects of noise on recognition memory. Per the effortfulness hypothesis (McCoy et al., 2005), we expect that processing speech in challenging listening environments requires additional processing resources that might otherwise be available for encoding speech in memory. This resource reallocation may be offset by speaker adaptations to the environment and to the listener. Here we compare recognition memory for conversational and clear speech sentences recorded in quiet (QS) and for sentences produced in response to the actual environment noise, i.e. noise adapted speech (NAS). Listeners heard 40 unique conversational and clear QS or NAS sentences mixed with 6-talker babble at SNRs of 0 or +3 dB. Following the exposure, listeners identified 80 sentences in quiet as old or new. Results showed that 1) increased intelligibility through conversational-to-clear speech modifications leads to improved recognition memory and 2) NAS presents a more naturalistic speech adaptation than QS, leading to better sentence recall for listeners. This experiment suggests that acoustic-phonetic modifications implemented in listener-oriented speech lead to improved speech recognition in challenging listening conditions and, crucially, to a substantial enhancement in recognition memory for sentences.

A Longitudinal Study of Speech Perception Skills and Device Characteristics of Adolescent Cochlear Implant Users

For pediatric cochlear implant (CI) users, CI processor technology, map characteristics, and fitting strategies are known to have a substantial impact on speech perception scores at young ages. It is unknown whether these benefits continue over time as these children reach adolescence. To document changes in CI technology, map characteristics, and speech perception scores in children between elementary grades and high school, and to describe relations between map characteristics and speech perception scores over time. A longitudinal design with participants 8-9-yr-old at session 1 and 15-18-yr-old at session 2. Participants were 82 adolescents with unilateral CIs, who are a subset of a larger longitudinal study. Mean age at implantation was 3.4 yr (range: 1.7-5.4), and mean duration of device use was 5.5 yr (range: 3.8-7.5) at session 1 and 13.3 yr (range: 10.9-15) at session 2. Speech perception tests at sessions 1 and 2 were the Lexical Neighborhood Test (LNT) presented at 70 dB SPL (LNT-70) and Bamford-Kowal-Bench sentences in quiet (BKB-Q) presented at 70 dB SPL. At session 2, the LNT was also administered at 50 dB SPL (LNT-50), and BKB sentences were administered in noise with a +10 dB SNR (BKB-N). CI processor technology type and CI map characteristics (coding strategy, number of electrodes, threshold levels, and comfort levels) were obtained at both sessions. Electrical dynamic range was computed, and descriptive statistics, correlations, and repeated-measures ANOVAs were employed. Participants achieved significantly higher LNT and BKB scores, at 70 dB SPL, at ages 15-18 than at ages 8-9 yr. Forty-two participants had 1-3 electrodes either activated or deactivated in their map between test sessions, and 40 had no change in number of active electrodes (mean change: -0.5; range: -3 to +2). After conversion from arbitrary clinical map units to charge-per-phase in nanocoulombs (nC), no significant difference was found for T levels across time. Average comfort levels (C levels) decreased by 19 nC. Seventy-three participants (89%) upgraded their CI processor technology type. At both sessions, significant correlations were found between electrical dynamic range (EDR) and all speech perception measures except LNT-50 (r range: .31 to .47; p < 0.01). Similarly, significant correlations were also found between C levels and all speech perception measures (r range: .29 to .49; p < 0.01). At session 2, a significant correlation was found between processor technology type and the LNT-50 scores (r = .38; p < 0.01). Significant improvement in speech scores was observed between elementary grades and high school for children who had used a CI since preschool. On average, T levels (nC) and electrode function remained stable for these long-term pediatric users. Analyses of maps did not allow for the determination of the exact cause of C level reductions, though power limitations in new processor systems and changes in perceived loudness over time are possible. Larger EDRs and higher C levels were associated with better speech scores. Newer speech processor technology was associated with better speech scores at a softer level.

Auditory rehabilitation of patients with neurofibromatosis Type 2 by using cochlear implants

The aim of this study was to determine whether patients with neurofibromatosis Type 2 (NF2) who have intact ipsilateral cochlear nerves can have open-set speech discrimination following cochlear implantation. Records of 7 patients with documented NF2 were reviewed to determine speech discrimination outcomes following cochlear implantation. Outcomes were measured using consonant-nucleus-consonant words and phonemes; Hearing in Noise Test sentences in quiet; and City University of New York sentences in quiet and in noise. Preoperatively, none of the patients had open-set speech discrimination. Five of the 7 patients had previously undergone excision of ipsilateral vestibular schwannoma (VS). One of the patients who received a cochlear implant had received radiation therapy for ipsilateral VS, and another was undergoing observation for a small ipsilateral VS. Following cochlear implantation, 4 of 7 patients with NF2 had open-set speech discrimination following cochlear implantation during extended follow-up (15-120 months). Two of the 3 patients without open-set speech understanding had a prolonged period between ipsilateral VS resection and cochlear implantation (120 and 132 months), and had cochlear ossification at the time of implantation. The other patient without open-set speech understanding had good contralateral hearing at the time of cochlear implantation. Despite these findings, 6 of the 7 patients were daily users of their cochlear implants, and the seventh is an occasional user, indicating that all of the patients subjectively gained some benefit from their implants. Cochlear implantation can provide long-term auditory rehabilitation, with open-set speech discrimination for patients with NF2 who have intact ipsilateral cochlear nerves. Factors that can affect implant performance include the following: 1) a prolonged time between VS resection and implantation; and 2) cochlear ossification.

A comparison of the speech recognition and pitch ranking abilities of children using a unilateral cochlear implant, bimodal stimulation or bilateral hearing aids

ObjectiveThe present study compared the speech recognition and pitch ranking abilities of normally hearing children (n=15) to children using a cochlear implant (CI) alone (n=8), bilateral hearing aids (HAs) (n=6), or bimodal stimulation (BMS) (n=9). It was hypothesised that users of BMS would score higher on tasks of speech and pitch perception than children using a CI alone, but not children using HAs. MethodsParticipants were assessed on tasks of monosyllabic word recognition in quiet, sentence recognition in quiet and noise (10dB signal-to-noise ratio), and a pitch ranking task using pairs of sung vowels one, half, and a quarter of an octave apart. ResultsThere were no significant differences between the mean percentage-correct scores of the four participant groups for either words in quiet or sentences in quiet and noise. However, the proportion of bimodal users who scored >80% correct (80%) was significantly greater than the proportion of high-scoring unilateral CI (25%) or bilateral HA users (17%). Contrary to expectations, there was also no significant difference between the pitch ranking scores of users of BMS and users of a CI alone for all three interval sizes (p<0.05, RM-ANOVA). However participants using only acoustic hearing (i.e. the NH and HA groups) scored significantly higher than participants using electrical stimulation (i.e. the CI and BMS groups) on the pitch ranking task (p<0.05; RM-ANOVA). ConclusionsContrary to findings in postlingually deafened adults, we found no significant bimodal advantage for pitch perception in prelingually deafened children. However, the performance of children using electrical stimulation was significantly poorer than children using only acoustic stimulation. Further research is required to investigate the contribution of the non-implanted ears of users of BMS to pitch perception, and the effect of hearing loss on the development of pitch perception in children.

Cochlear Implant Characteristics and Speech Perception Skills of Adolescents With Long-Term Device Use

Updated cochlear implant technology and optimized fitting can have a substantial impact on speech perception. The effects of upgrades in processor technology and aided thresholds on word recognition at soft input levels and sentence recognition in noise were examined. We hypothesized that updated speech processors and lower aided thresholds would allow improved recognition of soft speech without compromising performance in noise. 109 teenagers who had used a Nucleus 22-cochlear implant since preschool were tested with their current speech processor(s) (101 unilateral and 8 bilateral): 13 used the Spectra, 22 the ESPrit 22, 61 the ESPrit 3G, and 13 the Freedom. The Lexical Neighborhood Test (LNT) was administered at 70 and 50 dB SPL and the Bamford Kowal Bench sentences were administered in quiet and in noise. Aided thresholds were obtained for frequency-modulated tones from 250 to 4,000 Hz. Results were analyzed using repeated measures analysis of variance. Aided thresholds for the Freedom/3G group were significantly lower (better) than the Spectra/Sprint group. LNT scores at 50 dB were significantly higher for the Freedom/3G group. No significant differences between the 2 groups were found for the LNT at 70 or sentences in quiet or noise. Adolescents using updated processors that allowed for aided detection thresholds of 30 dB HL or better performed the best at soft levels. The BKB in noise results suggest that greater access to soft speech does not compromise listening in noise.

Reception Thresholds for Sentences in Quiet and Noise for Monolingual English and Bilingual Mandarin-English Listeners

Bilingual (BL) listeners' difficulties in adverse noise conditions are exacerbated when perceiving their second language (L2) relative to their first language (L1). Perception of L2 is also significantly poorer by BL listeners compared to native monolingual (ML) listeners. The purpose of the study was to examine the effect of stationary and nonstationary energetic noise maskers on L1 and L2 speech perception in native and nonnative listeners. A mixed multivariate quasi-experimental design was employed. Two groups of 12 ML English-speaking and BL Mandarin-English-speaking normal-hearing young adult female volunteers participated. An adaptive technique was employed to determine reception thresholds for sentences (RTSs) in quiet and in backgrounds of competing continuous and interrupted noise. The noises differed only in their temporal continuity. The sentence stimuli employed consisted of the Hearing in Noise Test (HINT) and the Mandarin Hearing in Noise Test (MHINT). ML participants received the HINT stimuli while the BL participants received both HINT and MHINT stimuli. Between-group differences in RTSs were examined for the same stimuli (i.e., HINT) and for L1 stimuli (i.e., HINT vs. MHINT). Within-group differences in RTSs were examined with the BL participants' perception of L1 and L2 stimuli (i.e., MHINT vs. HINT). The amount of "release from masking" (i.e., the difference of RTS signal-to-noise ratios [SNRs] in interrupted and continuous noise) was also examined between and within groups. In quiet there was no significant difference in mean RTSs between the BL and ML participants with their respective L1 stimuli; MLs had significantly lower mean RTSs in English compared to the BLs; and mean RTSs for the BLs were significantly lower for L1 versus L2 stimulus. In noise, a significantly higher RTS SNR was found for the MLs in continuous noise but not interrupted noise for L1 stimuli compared to the BLs; BLs had a significantly higher mean RTSs in English compared to the MLs; and BLs had significantly higher mean RTSs for L2 versus L1 stimuli. The release from masking was significantly greater for MLs compared to BLs with their respective L1 stimuli and with the same English stimuli. There was no significant difference for the BLs' release from masking with L1 versus L2 stimulus. BL listeners display significantly poorer performance when perceiving nonnative L2 sentences in quiet and in continuous and interrupted noise relative ML listeners. When listening to their respective native L1 sentences, only a difference in continuous noise was found. This difference was attributed to differential masking effect on the English stimuli. Similar performance in the interrupted noise between the ML and BL participants with L1 stimuli and the equivalent release from masking with the BL participants for both L1 and L2 stimuli suggest comparable basic auditory temporal resolving capacities between these ethnic groups.

Active Middle Ear Implant Compared With Open-Fit Hearing Aid in Sloping High-Frequency Sensorineural Hearing Loss

To compare 2 open-ear hearing solutions for sloping high-frequency sensorineural hearing loss: open-fit hearing aid (HA) and active middle ear implant (AMEI). Within-subjects prospective design. Tertiary referral hospital. PATIENTS AND DEVICES: Fourteen patients with sloping, high-frequency sensorineural hearing loss were recruited from 39 patients previously implanted with an AMEI and 10 agreed to participate, ranging in age from 44 to 73 years (mean, 59 yr). Patients were selected because their hearing thresholds (500-3,000 Hz) qualified them for both AMEI and open-fit HA use. All patients received a Vibrant Soundbridge (Vibrant MED-EL) for an average of 25.1 months before data collection and used their AMEI on a daily basis. The open-fit HA used in this study was the Delta 8000 (Oticon). Both study devices have been fit with the specific fitting strategies as recommended by the manufacturer. Sound-field hearing thresholds, Freiburger monosyllabic words in quiet, speech reception thresholds for 50% correct recognition for Freiburger numbers and for Oldenburg sentences in quiet, and speech reception thresholds for 50% correct recognition for Oldenburg sentences in noise. Both HA and AMEI conditions showed significantly better sound-field thresholds and speech recognition on monosyllabic word and sentence tests in quiet and in noise than in the unaided condition. A comparison of aided conditions revealed that, in the AMEI-aided condition, high-frequency audibility and speech discrimination scores in quiet and in noise were significantly better than those in the open-fit HA. Both open-fit HAs and AMEIs provided audiologic benefit to patients with sloping high-frequency sensorineural hearing loss. However, despite overlapping indication criteria for the 2 devices, performance with the AMEI was significantly better for the AMEI than for the open-fit HA.

Evaluation of Speech Recognition in Noise with Cochlear Implants and Dynamic FM

Use of personal frequency-modulated (FM) systems significantly improves speech recognition in noise for users of cochlear implants (CIs). Previous studies have shown that the most appropriate gain setting on the FM receiver may vary based on the listening situation and the manufacturer of the CI system. Unlike traditional FM systems with fixed-gain settings, Dynamic FM automatically varies the gain of the FM receiver with changes in the ambient noise level. There are no published reports describing the benefits of Dynamic FM use for CI recipients or how Dynamic FM performance varies as a function of CI manufacturer. To evaluate speech recognition of Advanced Bionics Corporation or Cochlear Corporation CI recipients using Dynamic FM vs. a traditional FM system and to examine the effects of Autosensitivity on the FM performance of Cochlear Corporation recipients. A two-group repeated-measures design. Participants were assigned to a group according to their type of CI. Twenty-five subjects, ranging in age from 8 to 82 years, met the inclusion criteria for one or more of the experiments. Thirteen subjects used Advanced Bionics Corporation, and 12 used Cochlear Corporation implants. Speech recognition was assessed while subjects used traditional, fixed-gain FM systems and Dynamic FM systems. In Experiments 1 and 2, speech recognition was evaluated with a traditional, fixed-gain FM system and a Dynamic FM system using the Hearing in Noise Test sentences in quiet and in classroom noise. A repeated-measures analysis of variance (ANOVA) was used to evaluate effects of CI manufacturer (Advanced Bionics and Cochlear Corporation), type of FM system (traditional and dynamic), noise level, and use of Autosensitivity for users of Cochlear Corporation implants. Experiment 3 determined the effects of Autosensitivity on speech recognition of Cochlear Corporation implant recipients when listening through the speech processor microphone with the FM system muted. A repeated-measures ANOVA was used to examine the effects of signal-to-noise ratio and Autosensitivity. In Experiment 1, use of Dynamic FM resulted in better speech recognition in noise for Advanced Bionics recipients relative to traditional FM at noise levels of 65, 70, and 75 dB SPL. Advanced Bionics recipients obtained better speech recognition in noise with FM use when compared to Cochlear Corporation recipients. When Autosensitivity was enabled in Experiment 2, the performance of Cochlear Corporation recipients was equivalent to that of Advanced Bionics recipients, and Dynamic FM was significantly better than traditional FM. Results of Experiment 3 indicate that use of Autosensitivity improves speech recognition in noise of signals directed to the speech processor relative to no Autosensitivity. Dynamic FM should be considered for use with persons with CIs to improve speech recognition in noise. At default CI settings, FM performance is better for Advanced Bionics recipients when compared to Cochlear Corporation recipients, but use of Autosensitivity by Cochlear Corporation users results in equivalent group performance.

A Predictive Model of Cochlear Implant Performance in Postlingually Deafened Adults

To develop a predictive model of cochlear implant (CI) performance in postlingually deafened adults that includes contemporary speech perception testing and the hearing history of both ears. Retrospective clinical study. Multivariate predictors of speech perception after CI surgery included duration of any degree of hearing loss (HL), duration of severe-to-profound HL, age at implantation, and preoperative Hearing in Noise Test (HINT) sentences in quiet and HINT sentences in noise scores. Consonant-nucleus-consonant (CNC) scores served as the dependent variable. To develop the model, we performed a stepwise multiple regression analysis. Tertiary referral center. Adult patients with postlingual severe-to-profound HL who received a multichannel CI. Mean follow-up was 28 months. Fifty-five patients were included in the initial bivariate analysis. Multichannel cochlear implantation. Predicted and measured postoperative CNC scores. The regression analysis resulted in a model that accounted for 60% of the variance in postoperative CNC scores. The formula is (pred)CNC score = 76.05 + (-0.08 x DurHL(CI ear)) + (0.38 x pre-HINT sentences in quiet) + (0.04 x long sev-prof HL(either ear)). Duration of HL was in months. The mean difference between predicted and measured postoperative CNC scores was 1.7 percentage points (SD, 16.3). The University of Massachusetts CI formula uses HINT sentence scores and the hearing history of both ears to predict the variance in postoperative monosyllabic word scores. This model compares favorably with previous studies that relied on Central Institute for the Deaf sentence scores and uses patient data collected by most centers in the United States.

Masking release at low sensation levels.

Previous results have shown that listeners with sensorineural hearing loss (SNHL) obtain about half of the masking release of their normal‐hearing (NH) counterparts. When speech is amplified sufficiently, listeners with SNHL may score like NH listeners in quiet and in steady noise, yet may obtain only half of the expected release from gated noise. We hypothesize that some of that deficiency may occur because of the impaired listeners’ low speech sensation levels, which results in decreased usefulness of the speech signal in the noise dips. In the current study, NH listeners were tested for their recognition of IEEE sentences in quiet, in steady noise, and in gated noise with the speech presented at varying sensation levels. At low levels (10–15 dB SL), NH listeners scored nearly 100% correct in quiet. In steady noise (at −10 dB signal‐to‐noise ratio) scores for low‐level stimuli were also similar to those obtained at higher SLs. However, at low SLs in gated noise, NH listeners demonstrated less masking release than expected, suggesting that audibility of speech in the dips of noise is important for masking release even when performance in quiet and in steady noise seems optimized. [Work supported by NIH 5R01DC008306.]

Subjective and Objective Results After Bilateral Cochlear Implantation in Adults

To assess and compare subjective and objective results after bilateral cochlear implantation with a special emphasis on time interval between the first and second implant. Clinical trial. Tertiary referral center. All consecutively bilaterally implanted adult patients who had used the second implant for more than 6 months were selected for the study. They had to have the mental capacity to answer questions regarding their hearing abilities and fill out a questionnaire (n = 34). Twenty-nine patients (85%) finally could be included in the study (age at first implantation, 31.0 +/- 16 yr [mean +/- standard deviation {SD}], time to second implantation, 5.6 +/- 5.7 yr [mean +/- SD]). In all patients, a full insertion (21 electrodes) of the implant was achieved. For the subjective part of the study, the patients were matched with unilaterally implanted subjects selected according to specified criteria. Sequential or simultaneous cochlear implantation with a Nucleus device. Speech comprehension measures were performed using the Oldenburger sentences in quiet and in noise with unilateral and bilateral implant use. Summation effect, head shadow effect, squelch effect, and interaural difference in quiet and noise were calculated. Advantage for binaural stimulation with respect to the unilateral condition was assessed for each individual. Additionally, a localization test was performed using 12 speakers arranged in a circle. Subjective benefit was assessed by a questionnaire (The Speech, Spatial and Qualities of Hearing Scale). Results were analyzed with special emphasis on effects of timing and intervals. There was a statistically significant advantage for the head shadow effect test (p < 0.05) when the sound source was located on the activated side. There was also a statistically significant correlation of the subjective and objective results and a strong correlation of the interaural difference of speech intelligibility in quiet and the time interval between the first and the second implant (p < 0.001; r = 55%). In the bi-implanted state, an interaural difference of 18 +/- 27% and 3 +/- 2.2 dB signal-to-noise ratio (mean +/- SD) was measured in quiet and noise, respectively. The mean results for the bilateral condition for the summation effect, the squelch effect, and speech discrimination in quiet were better than in the unilateral condition but were not statistically significant. The subjective results of the bilateral group were better in all categories than the results of the unilateral group but were just below statistical significance. Speech understanding in noise is improved with bilateral cochlear implantation with unambiguous evidence that the second implant expands the sound field for effective speech recognition. Communication in daily life is facilitated, as determined by the subjective Speech, Spatial and Qualities of Hearing Scale test. The correlation of the subjective and objective results confirms the practical benefits in daily activities. Although there was improvement with a second Cochlear implant even after a long implantation interval, short intervals lead to better results.

Speech Recognition in Cochlear Implant Recipients

HiRes (HR) 120 is a sound-processing strategy purported to offer an increase in the precision of frequency-to-place mapping through the use of current steering. This within-subject study was designed to compare speech recognition as well as music and sound quality ratings for HR and HR 120 processing. Cochlear implant/tertiary referral center. Eight postlinguistically deafened adults implanted with an Advanced Bionics CII or HR 90K cochlear implant. STUDY DESIGN/MAIN OUTCOME MEASURES: Performance with HR and HR 120 was assessed during 4 test sessions with a battery of measures including monosyllabic words, sentences in quiet and in noise, and ratings of sound quality and musical passages. Compared with HR, speech recognition results in adult cochlear implant recipients revealed small but significant improvements with HR 120 for single syllable words and for 2 of 3 sentence recognition measures in noise. Both easy and more difficult sentence material presented in quiet were not significantly different between strategies. Additionally, music quality ratings were significantly better for HR 120 than for HR, and 7 of 8 subjects preferred HR 120 over HR for listening in everyday life. HR 120 may offer equivalent or improved benefit to patients compared with HR. Differences in performance on test measures between strategies are dependent on speech recognition materials and listening conditions.

Perception of speech by prelingual pre-adolescent and adolescent cochlear implant users

This study was undertaken to assess the speech perception benefits, 24 months after cochlear implantation (CI), in 20 young people (age at CI, 8–18.5 years) with prelingual profound hearing loss, in addition to the use of a proposed CI candidacy assessment profile. Speech perception was evaluated in terms of word and sentence perception before CI, and at six-monthly intervals for two years after CI. Before undergoing CI, all participants were tested on a pre-implantation assessment profile. Compared to the pre-CI findings, group results over 24 months post-CI demonstrated improved speech perception abilities reaching, on average, 46% for word recognition, 71.3% for sentences in quiet, and 33.6% for sentences in noise. Pre-CI profile scores correlated significantly with all speech perception results obtained 24 months after CI. Thus, despite their relatively late ages at implantation, all participants showed gradually improving performance in speech perception. The results showed a high variability in the outcomes of the participants. The pre-CI profile appeared to be useful in formulating realistic expectations of CI outcome during pre-implantation consultations, suggesting that expectations can and should be managed according to each patient's pre-implantation assessment.SumarioSe llevó a cabo este estudio para evaluar los beneficios en la percepción del lenguaje, 24 meses después de la implant-ación coclear (CI), en 20 personas jóvenes (edad en la CI de 8-18.5 años), con sordera prelingüística profunda, en quienes se usó un perfil propuesto de evaluación para la candidatura a la CI. La percepción del lenguaje se evaluó en términos de percepción de palabras y oraciones antes de la CI y a intervalos de seis meses, durante dos años, después de la CI. Antes de la CI todos los participantes fueron examinados con un perfil de evaluación pre-implantación. Comparados con los hallazgos pre-CI, los resultados del grupo después de 24 meses de la CI mostraron mejoría en las habilidades para la percepción del lenguaje alcanzando, en promedio, 46% para el reconocimiento de palabras, 71.3% para oraciones sin ruido y 33.6% para oraciones con ruido. Las puntuaciones en el perfil pre-CI correlacionaron significativamente con todos los resultados de percepción del lenguaje obtenidos 24 meses después de la CI. Así, a pesar de las edades de implantación relativamente tardías, todos los participantes mostraron un desempeño gradual-mente mejor en la percepción del lenguaje. Los resultados mostraron una gran variabilidad en los resultados de los participantes. El Perfil pre-CI parece ser útil para formular expectativas realistas sobre los resultados de la CI durante las consultas pre-implante, sugiriendo que las expectativas pueden y deben ser manejadas de acuerdo con las evaluaciones pre-implantación de cada paciente.

A New Combined Speech Processor for Electric and Acoustic Stimulation – Eight Months Experience

Purpose: Electric acoustic stimulation (EAS) relies on the preservation of low-frequency hearing and adequate amplification of these frequencies. EAS has been achieved by fitting the cochlear implant (CI) speech processor together with an ipsilateral in-the-ear hearing aid. This study will evaluate the outcomes when CI/EAS users upgrade to a new combination of hearing aid and speech processor in 1 device (DUET™). Method: Nine EAS patients participated in this study. Before switchover and after 2 and 8 months of DUET device use, they were assessed using monosyllables and sentences in quiet and in noise. Additionally, a questionnaire, the Abbreviated Profile for Hearing Aid Benefit (APHAB), was used to evaluate subjective impressions. Results: All subjects performed equally well, or even better, after switchover. This was also demonstrated over time. The participants with EAS before switchover performed equally afterwards, while those who used CI only did markedly better with the new device, especially in noisy conditions. Slight preference for the new system was also demonstrated with the APHAB. Conclusion: All subjects showed benefit in noise; CI-only users before switchover particularly benefited from the new hearing system. Those who applied EAS before switchover performed equally well. The DUET allows individuals better access to EAS.

Comparison of Speech Recognition and Localization Performance in Bilateral and Unilateral Cochlear Implant Users Matched on Duration of Deafness and Age at Implantation

The purpose of this investigation was to compare speech recognition and localization performance of subjects who wear bilateral cochlear implants (CICI) with subjects who wear a unilateral cochlear implant (true CI-only). A total of 73 subjects participated in this study. Specifically, of the 73 subjects, 64 (32 CICI and 32 true CI-only) participated in the word recognition testing; 66 (33 CICI and 33 true CI-only) participated in the sentence recognition testing; and 24 (12 CICI and 12 true CI-only) participated in the localization testing. Because of time constraints not all subjects completed all testing. The average age at implantation for the CICI and true CI-only listeners who participated in the speech perception testing was 54 and 55 yrs, respectively, and the average duration of deafness was 8 yrs for both groups of listeners. The average age at implantation for the CICI and true CI-only listeners who participated in the localization testing was 54 and 53 yrs, respectively, and the average duration of deafness was 10 yrs for the CICI listeners and 11 yrs for the true CI-only listeners. All speech stimuli were presented from the front. The test setup for everyday-sound localization comprised an eight-speaker array spanning, an arc of approximately 108 degrees in the frontal horizontal plane. Average group results were transformed to Rationalized Arcsine Unit scores. A comparison in performance between the CICI score and the true CI-only score in quiet revealed a significant difference between the two groups with the CICI group scoring 19% higher for sentences and 24% higher for words. In addition, when both cochlear implants were used together (CICI) rather than when either cochlear implant was used alone (right CI or left CI) for the CICI listeners, results indicated a significant binaural summation effect for sentences and words. The average group results in this study showed significantly greater benefit on words and sentences in quiet and localization for listeners using two cochlear implants over those using only one cochlear implant. One explanation of this result might be that the same information from both sides are combined, which results in a better representation of the stimulus. A second explanation might be that CICI allow for the transfer of different neural information from two damaged peripheral auditory systems leading to different patterns of information summating centrally resulting in enhanced speech perception. A future study using similar methodology to the current one will have to be conducted to determine if listeners with two cochlear implants are able to perform better than listeners with one cochlear implant in noise.

Reception Thresholds for Sentences in Quiet, Continuous Noise, and Interrupted Noise in School-Age Children

Sentence recognition in noise was employed to investigate the development of temporal resolution in school-age children. Eighty children aged 6 to 15 years and 16 young adults participated. Reception thresholds for sentences (RTSs) were determined in quiet and in backgrounds of competing continuous and interrupted noise. In the noise conditions, RTSs were determined with a fixed noise level. RTSs were higher in quiet for six- to seven-year-old children (p = .006). Performance was better in the interrupted noise evidenced by lower RTS signal-to-noise ratios (S/Ns) relative to continuous noise (p < .0001). An effect of age was found in noise (p < .0001) where RTS S/Ns decreased with increasing age. Specifically, children under 14 years performed worse than adults. "Release from masking" was computed by subtracting RTS S/Ns in interrupted noise from continuous noise for each participant. There was no significant difference in RTS S/N difference scores as a function of age (p = .057). Children were more adversely affected by noise and needed greater S/Ns in order to perform as well as adults. Since there was no effect of age on the amount of release from masking, one can suggest that school-age children have inherently poorer processing efficiency rather than temporal resolution.