摘要:

Objective:This study was designed to determine the prevalence of minimal sensorineural hearing loss (MSHL) in school-age children and to assess the relationship of MSHL to educational performance and functional status.Design:To determine prevalence, a single-staged sampling frame of all schools in the district was created for 3rd, 6th, and 9th grades. Schools were selected with probability proportional to size in each grade group. The final study sample was 1218 children. To assess the association of MSHL with educational performance, children identified with MSHL were assigned as cases into a subsequent case-control study. Scores of the Comprehensive Test of Basic Skills (4th Edition) (CTBS/4) then were compared between children with MSHL and children with normal hearing. School teachers completed the Screening Instrument for Targeting Education Risk (SIFTER) and the Revised Behavior Problem Checklist for a subsample of children with MSHL and their normally hearing counterparts. Finally, data on grade retention for a sample of children with MSHL were obtained from school records and compared with school district norm data. To assess the relationship between MSHL and functional status, test scores of all children with MSHL and all children with normal hearing in grades 6 and 9 were compared on the COOP Adolescent Chart Method (COOP), a screening tool for functional status.Results:MSHL was exhibited by 5.4% of the study sample. The prevalence of all types of hearing impairment was 11.3%. Third grade children with MSHL exhibited significantly lower scores than normally hearing controls on a series of subtests of the CTBS/4; however, no differences were noted at the 6th and 9th grade levels. The SIFTER results revealed that children with MSHL scored poorer on the communication subtest than normal-hearing controls. Thirty-seven percent of the children with MSHL failed at least one grade. Finally, children with MSHL exhibited significantly greater dysfunction than children with normal hearing on several subtests of the COOP including behavior, energy, stress, social support, and self-esteem.Conclusions:The prevalence of hearing loss in the schools almost doubles when children with MSHL are included. This large, education-based study shows clinically important associations between MSHL and school behavior and performance. Children with MSHL experienced more difficulty than normally hearing children on a series of educational and functional test measures. Although additional research is necessary, results suggest the need for audiologists, speech-language pathologists, and educators to evaluate carefully our identification and management approaches with this population. Better efforts to manage these children could result in meaningful improvement in their educational progress and psychosocial well-being.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:We describe an animal model of auditory neuropathy in which subjects have extensive, scatered inner haircell loss but with a relatively intact outer haircell population.Design:Such a pattern of cochlear haircell damage can be produced in the chinchilla by treatment with the anticancer agent carboplatin.Results:In these subjects, otoacoustic emissions (OAEs) and cochlear microphonics remain normal while auditory brain stem evoked potential (ABR) thresholds are significantly elevated. However, in the same subjects, central auditory neurons (in the inferior colliculus) have response thresholds that are considerably lower (by up to 50 dB) than ABR thresholds. These findings parallel the characteristics of auditory neuropathy in humans, in which absent or abnormal ABRs are recorded in patients with only mild to moderate audiometric thresholds and preserved OAEs.Conclusions:We suggest that scattered inner haircell lesions also can result from long-term cochlear hypoxia, and we propose that this is a likely candidate for the etiology of many types of auditory neuropathy in human subjects.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:To demonstrate the viability of bone conduction as a novel method for stimulation of distortion product otoacoustic emissions (DPOAEs).Design:DPOAEs were recorded from a single ear of 23 normally hearing adults using bone and air conduction for the delivery of stimulus tones. Exploration of the input-output function was performed by varying stimulus frequency and magnitude.Results:Bone-stimulated emissions demonstrated similar characteristics to those obtained through standard air transmission techniques. Characteristic nonlinear DPOAE growth was found as the magnitude of the higher frequency stimulus tone, L2, was increased monotonically with other parameters fixed. Bilateral stimulation due to using bone conduction did not saturate the mechanisms of emission suppression. Emission magnitude was not altered substantially by occlusion of the ear canal.Conclusion:Bone conduction can be used successfully to elicit DPOAEs. Absolute comparison of air- and bone-stimulated DPOAEs was difficult because of imprecise calibration of the bone conductors for each individual and particular placement. Properties unique to bone conduction, such as simultaneous bilateral stimulation and reduction of stimulus magnitude in the ear canal, may make bone conduction attractive for clinical measurement of DPOAEs.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:The aim was to develop an assessment procedure that was independent of language and speech production ability, to test speech feature discrimination in severe-profoundly deaf children 2 to 4 yr of age.Design:The procedure being trialed was adapted from existing procedures. The child was required to respond with a game-like motor response to a "change" in a speech stimulus that was being presented repeatedly through a speaker. The change occurred at randomly determined times, and false alarm responses were measured during the waiting periods (while the child waited for the change). Two- to four-yr-old normally hearing children and hearing-impaired children using hearing aids and a group of 4-yr-old hearing-impaired children using cochlear implants were assessed on the task.Results:More than 82% of the 3- and 4-yr-old normally hearing and hearing-impaired children were able to complete the testing for the eight speech sound contrasts within three 20 minute sessions. Fifty percent of the 2-yr-old normally hearing and hearing-impaired children were able to condition and complete the task. All of the normally hearing children who completed the task successfully discriminated all speech sound contrasts. The performance of the hearing-impaired children using hearing aids was influenced by the degree of hearing loss and the type of speech contrast being tested. Similarly, the average performance of the children using cochlear implants was better for easier contrasts such as /ba/bi/ with contrasting vowel formant cues.Conclusions:This procedure has potential for use as a reliable clinical and research tool for assessing the development of auditory discrimination ability in 2- to 4-yr-old severe-profoundly deaf children.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:This study examined the control of oral-nasal balance by pediatric cochlear implant (CI) users, with and without auditory feedback.Design:Five CI users read lists of sentences in two conditions: with their devices on and with their devices off. Their oral-nasal balance (ratio of energy radiated from the oral and nasal cavities) was measured in both conditions and compared with values obtained from children with normal hearing.Results:CI users showed different patterns of abnormal oral-nasal balance with their devices off, but they generally achieved values that were closer to normal when their devices were on.Conclusions:The results suggest that children with CIs use the auditory signal provided by their device to improve their control of nasalization. It is also possible that at least part of the changes in oral-nasal balance were driven by changes in related articulatory parameters.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:The major objective of the study was to evaluate the effectiveness of long-term training for an adult subject fitted with the Tactaid VII vibrotactile aid. A secondary goal of this work was to provide a detailed description of how the KTH Tracking Procedure can be used for training and evaluative purposes.Design:An adult male subject was fitted with a Tactaid VII tactile aid and provided with weekly training sessions in its use over an 18 mo period. The KTH Tracking Procedure was used for training and to record the subject's performance over time. Additional post-training measures included sentence lists and consonants presented in an [aCa] frame.Results:The results obtained showed a 19 to 37% improvement in tracking rate when lipreading was supplemented by the Tactaid VII compared with those obtained via lipreading alone. Attempts to supplement lipreading with auditorily presented voicing cues did not result in improved performance. At the completion of the training program, additional tracking measures were obtained with an unfamiliar female speaker. The results of this testing again showed enhanced performance when the Tactaid VII supplemented lipreading. Post-training testing with sentence materials yielded scores of 29.8% correct for lipreading alone and 39.9% correct for lipreading plus the Tactaid VII. The subject's scores for consonants in [aCa] testing were 47.0% correct for lipreading alone and 60.1% correct for lipreading plus the Tactaid VII.Conclusions:The study showed that the use of the Tactaid VII resulted in improved lipreading performance for a range of materials and with two different speakers. The results also highlight the value of the KTH Tracking Procedure for testing and training purposes.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Objective:The purpose of this study was to evaluate the reliability and validity of the real ear to coupler difference (RECD) and the real ear to dial difference (REDD) in predicting real ear SPL (RESPL).Design:The RESPL, RECD, and REDD were measured in the right ear of 24 normal-hearing subjects using probe microphone equipment and both insert and supra-aural earphones. The phones and probe tube were removed and replaced, and the RECD and REDD were remeasured.Results:RESPL was predicted using the RECD for insert earphone data and the REDD for supra-aural earphone data. Reliability estimates were calculated as the difference between test and retest values for the RECD and REDD. Validity estimates were calculated as the difference between measured and predicted RESPL. Results indicate that the RECD and REDD have equal and high reliability and validity in predicting RESPL.Conclusions:It is concluded that the RECD and REDD may be used as level-independent HL to SPL transforms as a substitute for in situ audiometric procedures.

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1998

数据来源: OVID