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Normal-hearing listeners gain important everyday benefits from having two ears, particularly for determining where sounds come from and for understanding speech in noisy environments. Users of two cochlear implants may have the opportunity to experience some of these bilateral advantages. The primary aim of this study was to document bilateral versus unilateral listening benefit in 15 postlinguistically deafened adults implanted simultaneously with two Harmony((R)) (HiRes 90K((R))) cochlear implants. Speech perception (in quiet and in noise) and localization accuracy were assessed for each ear alone and both ears together. Subjects showed improved sound localization and better speech perception in quiet and in noise when using two implants compared with using one implant alone. [ABSTRACT FROM AUTHOR]

Objective: To demonstrate benefits for speech perception and everyday listening in quiet and in noise with a speech-enhancement strategy called ClearVoice, which was designed to improve listening in complex acoustic environments without compromising hearing in quiet., Study Design: A 2-week randomized crossover design was used to evaluate ClearVoice in 46 adults unilaterally implanted with a CII/HiRes 90K cochlear implant who had at least 6 months experience with HiRes Fidelity 120 sound processing. Speech perception was assessed using the AzBio sentences presented in quiet, in speech-spectrum noise and in multitalker babble. Subjective listening benefit and strategy preference were assessed with a questionnaire. ClearVoice has 3 gain settings (low, medium, and high), each intended as a full-time listening option according to individual preference. Speech understanding after acute use of ClearVoice-low was compared with HiRes Fidelity 120 during an initial test session. Speech perception abilities were compared with HiRes Fidelity 120 after 2 weeks of exclusive use of ClearVoice-medium, and after 2 weeks of exclusive use of ClearVoice-high. During a fifth week, participants were fit with 3 programs for comparison (HiRes Fidelity 120, ClearVoice-medium, and ClearVoice-high), after which, they reported preference and everyday listening benefits via a questionnaire., Results: ClearVoice significantly improved speech understanding in speech-spectrum noise and multitalker babble, did not compromise listening in quiet, was preferred for everyday listening, and provided improved hearing in real-life situations., Conclusion: ClearVoice improves hearing in noise for cochlear implant recipients who use HiRes Fidelity 120 sound processing.

Objective: This study consisted of a within-subjects comparison of speech recognition and patient preference when subjects used two different cochlear implant speech processing strategies with a Clarion 1.2 (enhanced bipolar) device: Simultaneous Analog Stimulation (SAS), and Continuous Interleaved Sampling (CIS). These two strategies used two different electrode configurations: the SAS strategy used bipolar stimulation, whereas the CIS strategy used monopolar stimulation., Study Design: This was a multicenter study that used a within-subjects balanced crossover design. Experience with the two strategies was replicated in each subject using an ABAB design. Order of strategy use was balanced across all subjects., Setting: The study was carried out at several cochlear implant centers affiliated with tertiary medical centers., Patients: Subjects consisted of 25 postlingually deafened adults who received a Clarion cochlear implant., Interventions: Total involvement by each subject was 14 weeks. Speech perception testing and sound quality assessments were performed after use with each strategy., Main Outcome Measures: Primary outcome measures include speech perception data and patient responses to questionnaires regarding speech and sound quality., Results: Analyses revealed that performance did not differ significantly by the strategy encountered first as relative to the strategy encountered second and that the order in which a strategy was used did not appear to affect subjects' eventual preference for a particular strategy. Although speech recognition scores tended to be higher for CIS for most of the test measures at most of the test intervals, the analysis of variance to evaluate differences in strategy did not reveal a significant effect of strategy. Further analysis of scores obtained at the replication interval, however, revealed that scores obtained with CIS were significantly higher than scores obtained with SAS on the Hearing in Noise Test sentences in quiet and noise. In addition, significantly more patients indicated a final preference for the CIS strategy than for the SAS strategy. Importantly, both the analysis evaluating order and the analysis evaluating strategy revealed significant effects of evaluation period, indicating that time/experience with the implant had a significant effect on scores for each strategy, regardless of the order in which it was used (first or second)., Conclusions: This study demonstrates that important learning occurs during the first several weeks of cochlear implant use, making it difficult to adequately compare performance with different speech processing strategies. However, the finding that patients often prefer the strategy they understand speech the best with supports the clinical practice of letting adult patients select their preferred strategy without formally evaluating speech perception with each available strategy.

Objective: This study compared speech perception benefits in adults implanted with the HiResolution (HiRes) Bionic Ear who used both conventional and HiRes sound processing. A battery of speech tests was used to determine which formats were most appropriate for documenting the wide range of benefit experienced by cochlear-implant users., Study Design: A repeated-measures design was used to assess postimplantation speech perception in adults who received the HiResolution Bionic Ear in a recent clinical trial. Patients were fit first with conventional strategies and assessed after 3 months of use. Patients were then switched to HiRes sound processing and assessed again after 3 months of use. To assess the immediate effect of HiRes sound processing on speech perception performance, consonant recognition testing was performed in a subset of patients after 3 days of HiRes use and compared with their 3-month performance with conventional processing., Setting: Subjects were implanted and evaluated at 19 cochlear implant programs in the USA and Canada affiliated primarily with tertiary medical centers., Patients: Patients were 51 postlinguistically deafened adults., Main Outcome Measures: Speech perception was assessed using CNC monosyllabic words, CID sentences and HINT sentences in quiet and noise. Consonant recognition testing was also administered to a subset of patients (n = 30) using the Iowa Consonant Test presented in quiet and noise. All patients completed a strategy preference questionnaire after 6 months of device use., Results: Consonant identification in quiet and noise improved significantly after only 3 days of HiRes use. The mean improvement from conventional to HiRes processing was significant on all speech perception tests. The largest differences occurred for the HINT sentences in noise. Ninety-six percent of the patients preferred HiRes to conventional sound processing. Ceiling effects occurred for both sentence tests in quiet., Conclusions: Although most patients improved after switching to HiRes sound processing, the greatest differences were seen in the 'poor' performers because 'good' performers often reached ceiling performance, especially on tests in quiet. Future evaluations of cochlear-implant benefit should make use of more difficult measures, especially for 'good' users. Nonetheless, a range of difficulty must remain in test materials to document benefit in the entire population of implant recipients., (Copyright 2004 S. Karger AG, Basel)

Objectives: To investigate the effect of age at cochlear implantation on the auditory development of children younger than 3 years and to compare these children's auditory development with that of peers with normal hearing., Design: Using a repeated-measures paradigm, auditory skill development was evaluated before and 3, 6, and 12 months after implantation. Data were compared with previously published data from cohorts with normal hearing., Participants: One hundred seven hearing-impaired children (age range, 12-36 months) who received a cochlear implant during clinical trials in North America., Main Outcome Measure: Auditory skill development was assessed using the Infant-Toddler Meaningful Auditory Integration Scale, a tool that provides a quantitative measure in children as young as newborns., Results: Infants and toddlers who receive implants show rapid improvement in auditory skills during the first year of device use regardless of age at implantation, although younger children achieve higher scores. Children who undergo implantation at a younger age acquire auditory skills nearer to those of their peers with normal hearing at a younger age. The mean rate of acquisition of auditory skills is similar to that of infants and toddlers with normal hearing regardless of age at implantation., Conclusion: Performing implantation in children with profound hearing loss at the youngest age possible allows the best opportunity for them to acquire communication skills that approximate those of their peers with normal hearing.

Data from Clarion cochlear implant pediatric clinical trials were examined retrospectively to uncover trends in candidacy and postimplant benefit over time. In particular, age at implantation, educational setting, and communication mode were examined with respect to speech perception performance after implantation. The results showed that 1) age at implantation is decreasing, 2) children in oral education programs obtain more benefit from a cochlear implant than children in total communication programs, 3) children who undergo implantation before 2 years of age show greater benefit than children who undergo implantation between 2 and 3 years of age, 4) more younger children are using oral communication than older children, and 5) more children with good auditory skills before implantation and more residual hearing are undergoing implantation. In sum, in the 11 years since implants have been available to children in the United States, candidacy criteria have evolved and benefit has increased as cochlear implant technology has advanced.

Objective: In 1998, clinical trials were initiated to evaluate the CLARION Multi-Strategy Cochlear Implant (Advanced Bionics Corp., Sylmar, CA, U.S.A.), a precurved electrode with an electrode positioning system (EPS) in adults with severe to profound hearing impairments. In 1999, clinical trials were initiated to assess the CLARION HiFocus electrode with EPS in a similar group of adults. The purpose of this retrospective study was to evaluate and compare the preoperative and 1-, 3-, and 6-month postoperative speech perception scores obtained by the first 56 patients implanted with the precurved electrode with EPS and the first 56 patients implanted with the HiFocus electrode with EPS. Speech strategy preferences were additionally noted and compared at each test interval for each group., Study Design: All subjects participated in preoperative testing with hearing aids and postoperative (1, 3 and 6 months) testing with either the precurved electrode with EPS or the HiFocus electrode with EPS. Demographic characteristics and preoperative and postoperative speech perception results were compared within and between the 2 groups., Setting: Data presented here were collected at cochlear implant programs affiliated with tertiary medical centers located in the United States and Canada that participated in the clinical trials., Patients: Patients were postlinguistically deafened adults who received a CLARION cochlear implant., Results and Conclusion: Within-group evaluations revealed that both groups demonstrated significant improvements on all speech perception measures when 1-month postoperative scores were compared with scores obtained preoperatively with hearing aids. Between-group comparison of demographic data showed that the HiFocus group had a significantly higher mean age at implant and a significantly longer mean duration of deafness than the precurved electrode with EPS group. Statistical comparison of mean speech perception scores showed no significant difference between subjects using the precurved electrode with EPS versus the HiFocus electrode with EPS at the preoperative, 1-, and 3-month test intervals. At the 6-month test interval, the mean CNC Monosyllabic Word Test score obtained by the HiFocus with EPS group was significantly better than the mean score obtained by the group with the precurved electrode with EPS (p < 0.05).

Preoperative and postoperative efficacy results are reported for the first 58 children with 18 months of implant experience in the United States. A within-subjects repeated-measures design was used to compare preoperative performance with hearing aids to postoperative performance with the CLARION Multi-Strategy Cochlear Implant. The results revealed significant improvement over time on all speech perception measures. Higher scores and faster rates of progress were demonstrated by the children who used oral communication compared to children who used total communication, especially older children. The overall results suggest higher levels of performance and more rapid progress in the development of listening skills than has been reported in previous clinical trials with children. The latter finding appears to be due to advances in implant technology and changes in the demographic characteristics of the study groups.

This study examined the speech perception performance of 71 postlingually deafened adults implanted with the CLARION Multi-Strategy Cochlear Implant. After 3 months of implant use, one third of the patients (n = 23) preferred to use the Simultaneous Analog Stimulation (SAS) strategy, and two thirds of them (n = 48) chose to use the Continuous Interleaved Sampler (CIS) strategy. The mean CID sentence scores were similar for the SAS and CIS user groups at the 3-month postoperative interval. In contrast, the mean CNC word score of the SAS users was significantly higher than the mean score of the CIS users after 3 months of implant experience. Patients who preferred to use SAS demonstrated significantly shorter duration of deafness at time of implantation than did the CIS users, whereas the CIS users demonstrated significantly higher preoperative sentence recognition scores than the SAS users. The results suggested that access to a preferred processing strategy improved the overall group performance of postlingually deafened adults in the present study compared to the results of previous studies in which only the CIS strategy was available to most patients with the Clarion.

Optimal comprehensive management of a child with SNHL involves constructive dialogue and coordination with the child's family and teachers. Not all children with SNHL benefit from conventional amplification, even after parents have invested significant amounts of money in hearing aids. Parents may encounter frustration and disappointment if their children fail to achieve communicative and academic goals they have established in their own mind. If the child is a potential candidate for cochlear implantation, this decision not only involves the risks (albeit modest) of surgery but also often a substantial financial commitment to help defray the cost of this sophisticated electronic device. The parents may encounter conflicting advice from friends and members of the adult deaf community about the benefit of cochlear implantation. Throughout the course of all of these difficult considerations, the health professionals caring for a child with hearing loss should be a source for information, guidance, and support to the family.

This study examined the development of visual attention in 5- to 13-year-olds who differed in their access to sound. Hearing children, deaf children with cochlear implants, and deaf children without implants participated in a task in which they were to respond to some visual signals and not others. The results of Experiment I indicated that the timing of developmental changes in visual selective attention was similar for all 3 groups, occurring around 8 years. The magnitude of age-related change differed among groups; hearing children and older deaf children using a cochlear implant reached higher levels of performance with age than did deaf children without enhanced access to sound. The results of Experiment 2 suggest that the developmental differences between deaf children with and without cochlear implants begin prior to 8 years and may be related to their use of environmental sounds to organize visual attention.

Hypothesis: The primary purpose of this study was to determine if children, > or =5 years old, with onset of deafness before the acquisition of spoken language (i.e., prelingually deafened) derived more benefit from multichannel cochlear implants than from conventional hearing aids. It was hypothesized that children who used oral communication (speech plus listening) would demonstrate higher levels of performance after implantation than children who used total communication (English sign system plus speech and listening)., Background: Previous research suggests that prelingually deafened children given implants at an older age derive limited benefit from these devices. Changes in candidacy criteria and advances in technology, however, may make cochlear implants a more viable treatment option for this group of patients., Methods: A repeated-measures design was to used to compare patients' preoperative performance with hearing aids to postoperative performance with the CLARION cochlear implant after 3 and 6 months of device use. Pre- and postoperative performance were analyzed separately for children who used oral and total communication., Results: Both groups of children (oral and total communication) demonstrated significant postoperative improvement on all outcome measures over time. Postoperative scores of the children who used oral communication were significantly higher than those of the children who used total communication on four of the five outcome measures., Conclusions: Prelingually deafened children who do not receive cochlear implants until > or =5 years of age derive significant benefit from current implant devices compared with that obtained with conventional hearing aids. The greatest benefit is derived by children who use oral communication, with much more limited benefit demonstrated by children who use total communication.

Objective: To evaluate the speech performance of children with the Clarion Multi-Strategy Cochlear Implant., Patients: Prelingually deafened children who had received the Clarion implant., Methods: The Spondee and Monosyllable Word Identification subtest of the Early Speech Perception test, the Glendonald Auditory Screening Procedure (GASP), and the Phonetically Balanced Kindergarten test (PB-K) were administered to subjects 3 and 6 months after implantation., Results: At 3 months, subjects' performance was higher than preoperatively with hearing aids. At 6 months, performance improved further. Scores were higher on the ESP and GASP than on the PB-K. The scores indicate better levels of speech recognition than were obtained with older implant processing strategies. Subjects varied considerably in their performance. The results are preliminary because of the small sample.

Objective: To compare the performance of English-speaking and German-speaking children with Clarion cochlear implants on the Meaningful Auditory Integration Scale (MAIS)., Subjects and Methods: Prelingually deafened German-speaking children and English-speaking children with Clarion cochlear implants were assessed on the MAIS pre- and postoperatively. Data were analyzed in terms of the absolute score, preoperatively and at two postoperative intervals, and the improvement score., Results and Discussion: Preoperatively, the MAIS scores of German-speaking children were slightly lower than those of English-speaking children. Postoperatively, this difference became more pronounced. Substantial deviation within each group of subjects was suggested by the size of the standard deviations.

Objective: To assess the auditory skills in everyday situations of prelingually deafened children with Clarion cochlear implants compared with hearing aids used preoperatively., Study Design: The Meaningful Auditory Integration Scale (MAIS) was used to determine the preoperative and postoperative auditory skills of the children., Results and Discussion: After implantation, the children showed improvement in three skill areas: bonding to the device, spontaneous alerting to sound in everyday situations, and ability to derive meaning from sound in the environment.

Within recent years, there has been a growing trend to lower the age at implantation below 2 years in children. The motivation for this trend is to provide children with access to auditory stimulation as early as possible, thereby taking advantage of crucial periods for speech and language development. Determining implant candidacy in very young children, however, poses numerous challenges and requires the development and evaluation of assessment procedures appropriate for this population. Issues in determining audiologic candidacy and evaluating implant benefit in young children are discussed. Measures that can be used to assess auditory development in this population and the application of some of these procedures in the pediatric study of the Clarion cochlear implant (Advanced Bionics Corp., Sylmar, Calif.) are also presented.

The speech intelligibility of 61 prelingually deaf children was measured prior to their receiving a multichannel cochlear implant (CI) and at subsequent intervals. The speech intelligibility of the implanted subjects was compared to that of three groups of subjects with profound hearing loss who used conventional hearing aids (HAs), grouped on the basis of unaided thresholds: "gold" (pure tone average [PTA] = 93 dB hearing level [HL]), "silver" (PTA = 103 dB HL), and "bronze" (PTA > or = 110 dB HL). Intelligibility was measured in terms of the percentage of words from a set of 10 sentences that were correctly understood by a panel of listeners. The speech intelligibility of the implanted subjects increased gradually over time, remaining relatively low throughout the first 2 years of implant use. After that time, the average speech intelligibility of the CI subjects surpassed that of the silver HA users. The gold HA subjects demonstrated speech intelligibility that was markedly better than that of the CI subjects, even after 3 1/2 or more years of implant use.

Perceptual skills were evaluated at two intervals of cochlear implant (CI) use in 24 children with prelingual deafness who received the Nucleus multichannel CI. Their performance was compared to that of age-matched children with prelingual profound hearing losses who used conventional hearing aids (HAs). The HA subjects were grouped by unaided thresholds: "gold" subjects (pure tone average of 92 dB hearing level) and "silver" subjects (pure tone average of 104 dB hearing level). The CI users' perceptual abilities increased significantly with time. At the "early" interval (mean, 2 months of CI use), performance of the CI and silver HA groups was similar on measures of phoneme, word, and sentence recognition; the gold HA subjects' performance was superior to that of the other groups. At the "late" interval, (mean, 2.5 years of CI use), CI subjects' performance exceeded that of the silver group on all measures, and was similar to that of the gold group on vowel recognition and auditory-plus-visual sentence recognition measures.

Clinical trials of the Clarion multichannel cochlear implant in postlingually deaf adults have been ongoing since 1991, and clinical investigation of the device in children is projected to begin in the first quarter of 1995. The purpose of this paper is to present some of the issues encountered in developing research protocols for clinical trials of cochlear implants in the pediatric population, with special reference to the protocol that will be employed in the Clarion pediatric investigation.

Speech perception skills of prelingually deafened children who used the multichannel Tactaid 7 (n = 10) were compared to those of a matched group of children who used the Nucleus 22 channel cochlear implant (n = 10). Group scores were compared on a closed-set test of word recognition and on an open-set test of phrase recognition in the pre-device condition and at a post-device interval after an average of 1.5 years of multichannel device use. The results revealed that the scores of the implant users improved significantly between the pre- and post-device intervals on all measures. Moreover, the scores of the implant users were significantly higher than those of the tactile aid users on all measures. In contrast, the scores of the tactile aid users showed negligible change over time, except on a test that evaluated open-set recognition of phrases with both auditory and visual cues. The results suggest that children can learn to recognize words and understand speech without lipreading with a multichannel implant, whereas children who used the multichannel tactile aid demonstrate limited speech recognition skills only if auditory/tactile cues are combined with lipreading.

This study examined the variables that contribute to the large individual differences in the speech perception skills of children with the Nucleus multichannel cochlear implant. Sixty-one children were tested on four measures of speech perception: two tests of closed-set word recognition, one test of open-set recognition of phrases, and one open-set monosyllabic word test, scored on the basis of the percentage of phonemes as well as words identified correctly. The results of a series of multiple regression analyses revealed that the variables of processor type, duration of deafness, communication mode, age at onset of deafness, length of implant use, and age implanted accounted for roughly 35% of the variance on two tests of closed-set word recognition, and 40% of the variance on measures that assessed recognition of words or phonemes in an open set. Length of implant use accounted for the most variance on all of the speech perception measures.

Speech perception skills were measured in five children who had received a 3M/House single-channel cochlear implant and were subsequently upgraded to a multichannel cochlear implant (Nucleus). A rationale was developed based upon performance with the single-channel device and anticipated performance with the multichannel device. All subjects demonstrated improved acoustic thresholds with the multichannel device. Three of the children demonstrated improvements on identification tasks and two on word recognition tasks.

This study investigates patterns of speech discrimination in profoundly hearing-impaired children who have received cochlear implants or tactile aids. The change/no change procedure was used to assess speech discrimination in these children. Three groups of subjects were tested: the first group used 3M/House single-channel cochlear implants; the second group used Nucleus 22-channel cochlear implants; and the third group used two-channel Tactaid II+ vibrotactile aids. Nine contrasts were constructed that assessed discrimination of suprasegmental and segmental speech features. Subjects were presented with stimulus trials in which stimuli changed during the trial or in which stimuli remained the same. Hits, misses, false alarms, and correct rejections were tallied and d' values were calculated for individual subjects for each contrast. Results indicated that different patterns of speech discrimination are provided by the three sensory prosthetic devices. For all contrasts, mean discrimination performance with the Nucleus device was better than that observed for the other two devices, despite the shorter duration of subject experience with this cochlear implant. In addition, interactions between device and speech contrast were not observed. Examination of individual subject performance revealed that each device group had a distribution of good to poor performers. The results suggest that the change/no change procedure is able to provide information regarding speech perception through sensory prosthetic devices despite existing differences in vocabulary and language skills of subjects.

The speech perception abilities of 19 children with onset of deafness before age 3 years was examined after they received the Nucleus multichannel cochlear implant. The children were divided into two groups based on age at onset of deafness: children with congenital deafness (n = 8) and children with onset of deafness after birth but before age 3 (n = 11). There was no statistically significant difference between the scores of the two groups of subjects on 12 of the 13 speech perception tests administered. This finding suggests that children who are born deaf have the potential to derive the same benefit from cochlear implants as do children who have had some exposure to spoken language before the onset of their deafness. Examination of performance in terms of communication mode revealed that prelingually deafened children with implants who used oral communication obtained significantly higher scores on only 2 of the 13 speech perception measures than did children who used total communication. The data suggest that communication mode does not appear to account for large differences in speech perception performance among prelingually deafened children with multichannel cochlear implants.

Speech intelligibility was measured in 31 children who used the 3M/House single-channel implant (n = 12), the Nucleus 22-Channel Cochlear Implant System (n = 15), or the Tactaid II + two-channel vibrotactile aid (n = 4). The subjects were divided into subgroups based on age at onset of deafness (early or late). The speech intelligibility of the experimental subjects was compared to that of children who were profoundly hearing impaired who used conventional hearing aids (n = 12) or no sensory aid (n = 2). The subjects with early onset of deafness who received their single- or multichannel cochlear implant before age 10 demonstrated the highest speech intelligibility, whereas subjects who did not receive their device until after age 10 had the poorest speech intelligibility. There was no obvious difference in the speech intelligibility scores of these subjects as a function of type of device (implant or tactile aid). On the average, the postimplant or tactile aid speech intelligibility of the subjects with early onset of deafness was similar to that of hearing aid users with hearing levels between 100 and 110 dB HL and limited hearing in the high frequencies. The speech intelligibility of subjects with late onset of deafness showed marked deterioration after the onset of deafness with relatively large improvements by most subjects after they received a single- or multichannel implant. The one subject with late onset of deafness who used a tactile aid showed no improvement in speech intelligibility.

Performance on speech perception, speech production, and language tests was measured over time in children who used the 3M/House or the Nucleus cochlear implant. The speech perception and production results demonstrated higher performance levels and faster rates of learning for the multichannel than for the single-channel users. The performance of the children with the single-channel implant on the speech perception and production measures reached a plateau by 1.5 years post implant, whereas the children using the multichannel device continued to show improvement after 2 or more years of implant use. Changes in language were limited over time with no obvious difference in performance as a function of type of implant.

The speech perception abilities of 37 children with cochlear implants (single-channel or multichannel) were examined as a function of age at onset of deafness. There was no significant difference in the speech perception abilities of implanted children who were born deaf and those of implanted children who lost their hearing during the first 3 years of life. In contrast, the performance of children whose age at onset of deafness was 5 years or later was significantly better than that of the children with congenital or early-acquired deafness on tests of stress pattern categorization, closed-set word identification, open-set identification of common phrases, and lipreading enhancement.

The performance of 28 children with the Nucleus multi-channel cochlear implant, who had used the device an average of 1.7 yr, was examined on a battery of speech perception measures. All children demonstrated better speech perception skills with the implant than they had in the preimplant condition with hearing aids. With the Nucleus implant, 61% of the children demonstrated some open-set speech recognition and another 14% demonstrated closed-set speech recognition. Scores on the tests were corrected for guessing and a hierarchy of test difficulty was developed. The results revealed systematic differences in performance as a function of perception task and test format. The results of regression analyses, which were performed to identify predictors of success, showed that communication mode made a significant unique contribution to the variance in performance among subjects on an open-set word recognition test. When the scores of the children who used oral or total communication were compared on the full battery of tests, however, there were few significant group differences.

Data are presented on the speech perception performance of two profoundly hearing-impaired subjects while using a two-channel vibrotactile aid (Tactaid II) or a new, seven-channel instrument. Both subjects, one a profoundly hearing-impaired teenager and one a postlingually deaf adult, are experienced users of tactile aids. The data suggest better recognition of speech features, words, environmental sounds, and enhancement of lipreading skills with the new multichannel instrument than with the two-channel device.

The speech perception abilities of deaf children with a single- or multi-channel cochlear implant are compared with those of deaf children who derive substantial benefit from conventional hearing aids. The children with hearing aids have unaided pure-tone thresholds ranging from 90- to 110-dB HL through at least 2000 Hz, and aided thresholds of 30- to 60-dB HL. The group data show that the speech perception scores of the subjects with hearing aids were significantly higher than those of the subjects with implants on a range of speech perception measures. Although a few subjects with implants achieved scores as high as those who used hearing aids, the majority did not. Even though the children with implants receive substantial benefit from their devices, they continue to have limited auditory perception abilities relative to their peers who derive benefit from conventional hearing aids. The data highlight the importance of establishing hearing aid benefit in potential candidates for implant.

The speech perception and production skills have been examined in a young deaf child who used a tactile aid for 2.5 years and subsequently received a multichannel cochlear implant. Although the differences were small, there was a trend of higher performance on nearly all speech perception measures following implantation than was observed after 2.5 years of tactile-aid use. Negligible changes occurred in her speech while wearing the tactile aid but substantial improvements appeared after she had used the multichannel implant for only 6 months.

Analyses were performed on the spontaneous speech samples produced by profoundly hearing-impaired children who used the 3M/House single-channel cochlear implant (n = 7), the Nucleus multichannel cochlear implant (n = 7), or the two-channel tactile aid, the Tactaid II (n = 12). Speech recordings were obtained in the predevice condition, and after 6- and 12-months use. The speech of the children in the three experimental groups was compared to that of a control group of subjects who used a tactile aid inconsistently and received minimal speech training. Several new analysis procedures were developed to describe adequately the characteristics of the children's speech. The results revealed that all three experimental groups and the control group showed an increase in their production of sounds classified as English phonemes in the postdevice conditions. It was apparent at both the 6- and 12-months postdevice intervals that the most dramatic improvements were made by the users of the Nucleus device. The changes made by the Tactaid and 3M/House users were similar. The subjects with the Nucleus device also developed more diverse phonetic repertoires over time than did the other experimental subjects. More subjects with the Nucleus device acquired fricatives, liquids, glides, voiceless consonants, and high front vowels than did the subjects in the other groups. The subjects in the control group developed the most limited phonetic repertoires.