Graeme Clark Collection
Permanent URI for this collection
Search Results
1 - 10 of 12
-
ItemThe effect of language knowledge on speech perception: what are we really assessing?( 1997)Objective: The authors examined whether open-set speech perception scores are limited by knowledge of vocabulary and syntax and further considered whether remediation of vocabulary and syntax will increase open-set speech perception scores. Study Design: This was a repeated-measures study design in the setting of a primary (elementary) school for the hearing impaired. Patients: The study population was composed of three hearing-impaired children using Nucleus 22-channel cochlear implant. Intervention: Intervention used was language remediation sessions. Main Outcome Measures: The main outcome measures were assessment of auditory-alone speech perception benefit using open-set words and sentences and assessment of syntactic knowledge using the Test of Syntactic Ability. Outcome measures were applied before and after remediation. Results: Child 1 and child 2 showed a significant postremediation improvement in their overall scores on the Test of Syntactic Ability and in their ability to perceive words learned during remediation. Child I and child 2 also showed a significant improvement in their scores on a modified Bamford-Kowal-Bench open-set sentence test, which specifically targeted grammatical constructs trained in remediation sessions. Conclusions: Remediation of language knowledge deficits significantly improved open-set speech perception for two children, suggesting a need to include language remediation in cochlear implant habilitation programs.
-
ItemWithin-subject comparison of speech perception benefits for congenitally deaf adolescents with an electrotactile speech processor and a cochlear implant( 1996)This study assessed speech perception benefits for three congenitally deaf adolescents who used an electrotactile speech processor (Tickle Talker™) and subsequently went on to use a Nucleus Minisystem 22 cochlear implant. Both devices provided significant and comparable benefits for all children in the device plus lipreading condition. All children benefited from the additional information provided by either the Tickle Talker™ or the cochlear implant, and were able to perceive speech information with these devices that was not available through either aided residual hearing or lipreading. None of the three children were able to understand open-set words or sentences using either hearing aids alone or Tickle Talker™ alone, without the aid of lipreading. Two of the children showed significant open-set speech perception benefits while using their cochlear implant alone.
-
ItemVowel imitation task: results over time for 28 cochlear implant children under the age of eight years( 1995)With increasing numbers of implanted children under the age of 4 years, numerous researchers have reminded us of the need for valid, sensitive, and reliable tests of developing speech perception.1,2 In addition to studies of the efficacy of implanted prostheses, there is a need to investigate the many variables that influence children's communicative performance, such as changes in speech-coding strategy, updated speech-processing systems, the effects of various training regimens, and the selection of educational and communication modes.
-
ItemWithin-subject comparison of speech perception benefits with a multiple-channel cochlear implant and tactile device( 1995)In order to adequately advise prospective cochlear implant patients and their families, a clinician must have a good knowledge of the potential for particular individuals to benefit from cochlear implants and other alternatives.
-
ItemA clinical report on vocabulary skills in cochlear implant users [Abstract]( 1994)Receptive vocabulary results are reported for 32 children, adolescents and prelinguistically deafened adults implanted with the 22-electrode cochlear implant at the Melbourne Cochlear Implant Clinic. Age at implantation ranged from 2 years, 6 months to 20 years and implant use ranged from 1 year to 7 years, 8 months. There were significant gains from pre- to postoperative assessments on the Peabody Picture Vocabulary Test (PPVT) for the majority of subjects. Rates of improvement found are compatible with previous reports on smaller numbers of implant users, but cannot be attributable unambiguously to use of the implant. The group postoperative performance was significantly higher than mean preoperative performance (n =25). The relationship of variables such as duration of implant use, duration of profound deafness and speech perception ability to improvement on the PPVT is discussed. Expressive vocabulary results on the Renfrew Word Finding Vocabulary Scale are reported for 11 of the subjects. Less substantial gains were made on this measure.
-
ItemA clinical report on speech production of cochlear implant users [Abstract]( 1994)Speech production results are reported for a group of 15 children, adolescents and prelinguistically deafened adults implanted with the 22-electrode cochlear implant. Age at implantation ranged from 5 years to 20 years and implant experience ranged from 1 year to 4 years, 7 months. On a speech intelligibility test using sentences seven implant users improved significantly over time. Mean group performance (n = 11) improved from 18% preoperatively to 43% postoperatively. Similarly on a test of articulation, eight implant users improved significantly over time and the group mean postoperative performance (n = 11) exceeded the preoperative performance (55% compared to 38%). This group effect was significant for consonants and blends but was nonsignificant for vowels. Improvements occurred for front, middle and back consonants, for stops, nasals, fricatives and glides and for voiceless and voiced consonants. Three implant users showed no significant gain on either test. The results suggest complex relationships between speech production performance and sensory information provided by a multichannel implant.
-
ItemPitch perception for different modes of stimulation using the Cochlear multiple-electrode prosthesis( 1994)Abstract not available due to copyright.
-
ItemRadiologic evaluation of multichannel intracochlear implant insertion depth( 1993)Postoperative plain film x-rays are necessary in all multichannel cochlear implant patients to confirm intracochlear position, detect possible electrode kinking, and provide a reference if postoperative slippage occurs. In addition, precise documentation of multichannel intracochlear electrode insertion depths is necessary for comparison of speech recognition results among patients and may be of use for future speech processing strategies. In the present study, a method has been devised, using a modified Stenver's view, to more accurately document insertion depths of the electrode array and location of individual electrodes on 50 multichannel cochlear implant patients. Surgical estimates of insertion depth are shown to have great variability in regard to distance along the basilar membrane when compared with x-ray documentation. Additionally, there is preliminary evidence that insertion depth, as determined by x-ray studies, has a strong correlation with open-set speech discrimination.
-
ItemA "Combionic Aid": Combined speech processing for a cochlear implant in one ear and speech processing hearing aid in the other ear [Abstract]( 1993)Independent use of a cochlear implant in one ear and a hearing aid in the other is not acceptable for many implant users with some residual hearing. Psychophysical evidence suggests that there are substantial interactions between acoustic and electrical signals including masking and loudness summation. These effects may contribute to the difficulty in using two independent devices and it is desirable to control the parameters of the electrical and acoustical signals far more accurately than is possible with two independent devices with separate microphones. In order to achieve this control we have developed a Combionic aid incorporating an implant and an 'in1planlcompatible' hearing aid controlled from the same speech processor. The new processor is particularly flexible and can implement a wide variety of speech processing strategies for combined acoustic and electrical stimulation. A benchtop prototype has been tested with five patients using a range of different speech tests. In general, patients do better when they use acoustic and electrical information simultaneously than they do with either alone. Some patients on some tests perform significantly better with the bimodal aid than they do with independent hearing aids and implant processors worn together. Wearable devices have now been built and evaluations of these devices are continuing.
-
ItemCombined electrical and acoustical stimulation using a bimodal prosthesis( 1993)A new device incorporating a cochlear implant speech processor and a speech-processing hearing aid for the un-implanted ear has been designed and tested with four severely hearing-impaired patients. The aim of the device is to provide a more acceptable and effective combination of electrical and acoustic signals to the two ears. When used monaurally, and binaurally in conjunction with the cochlear implant, the speech-processing hearing aid mean scores for open-set sentences, words, and consonants were as good as or better than the mean scores for the patients' own conventional hearing aids. Some patients improved much more than did others. Although not conclusive, these results are encouraging, especially as they were achieved with a laboratory prototype that did not allow the patients to become accustomed to the processor in everyday situations.