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M J Osberger

Publications and source records attributed to M J Osberger.

At least 37 records · Page 2Linked to original sources
PubMed1997

Speech recognition performance of pediatric Clarion patients.

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.

Adolescent↗
PubMed1997

Comparative study of English- and German-speaking children with the Clarion cochlear implant.

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.

Adolescent↗
PubMed1995

Lexical effects on spoken word recognition by pediatric cochlear implant users.

OBJECTIVE: The purposes of this study were 1) to examine the effect of lexical characteristics on the spoken word recognition performance of children who use a multichannel cochlear implant (CI), and 2) to compare their performance on lexically controlled word lists with their performance on a traditional test of word recognition, the PB-K. DESIGN: In two different experiments, 14 to 19 pediatric CI users who demonstrated at least some open-set speech recognition served as subjects. Based on computational analyses, word lists were constructed to allow systematic examination of the effects of word frequency, lexical density (i.e., the number of phonemically similar words, or neighbors), and word length. The subjects' performance on these new tests and the PB-K also was compared. RESULTS: The percentage of words correctly identified was significantly higher for lexically "easy" words (high frequency words with few neighbors) than for "hard" words (low frequency words with many neighbors), but there was no lexical effect on phoneme recognition scores. Word recognition performance was consistently higher on the lexically controlled lists than on the PB-K. In addition, word recognition was better for multisyllabic than for momosyllabic stimuli. CONCLUSIONS: These results demonstrate that pediatric cochlear implant users are sensitive to the acoustic-phonetic similarities among words, that they organize words into similarity neighborhoods in long-term memory, and they use this structural information in recognizing isolated words. The results further suggest that the PB-K underestimates these subjects' spoken words recognition.

Age of Onset↗
PubMed1995

Speech perception skills of children with multichannel cochlear implants or hearing aids.

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.

Audiometry, Pure-Tone↗
PubMed1995

Issues in protocol design for cochlear implant clinical trials in children: the Clarion Pediatric Study.

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.

Child↗
PubMed1995

Speech intelligibility of implanted children.

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.

Child, Preschool↗
PubMed1995

Comparison of multichannel tactile aids and multichannel cochlear implants in children with profound hearing impairments.

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.

Child↗
PubMed1994

Variables affecting implant performance in children.

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.

Adolescent↗
PubMed1994

Single-channel to multichannel conversions in pediatric cochlear implant recipients.

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.

Adolescent↗
PubMed1993

Speech intelligibility of children with cochlear implants, tactile aids, or hearing aids.

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.

Age Factors↗
PubMed1993

Prelingually deafened children's performance with the nucleus multichannel cochlear implant.

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.

Acoustic Stimulation↗
PubMed1993

A comparison of speech discrimination with cochlear implants and tactile aids.

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.

Acoustic Stimulation↗
PubMed1992

Longitudinal evaluation of communication skills of children with single- or multichannel cochlear implants.

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.

Acoustic Stimulation↗
PubMed1991

Independent evaluation of the speech perception abilities of children with the Nucleus 22-channel cochlear implant system.

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.

Adolescent↗