The purpose of this investigation was to determine if the performance-intensity function for spondees delivered via bone conduction (using the Radioear E-72 and Pracitronic KH-70) differed from the performance-intensity function for air conduction (using TDH-39 earphones). A secondary consideration addressed in this study was the comparison of the discrimination scores using the three transducers. Performance-intensity functions for spondee thresholds were calculated on 12 normal hearing subjects using two bone conduction vibrators, the Radioear B-72 and Pracitronic KH-70, and TDH-39 earphones. Results indicated that there was no significant difference between the performance-intensity function of speech via bone conduction as compared to speech via air conduction. Also, there was no difference between the Radioear b-72 and Pracitronic KH-70 bone conduction vibrators. Discrimination scores also gave similar results between transducers. In conclusion, the results of this study suggest that the use of speech tests, such as the speech reception threshold and discrimination tests, which were originally designed for use via air conduction can safely be used for bone conduction.

The ability to understand speech is, for all practical purposes, the most important aspect of hearing.¹ The most common method of assessing hearing is through pure tone audiometry. However, the great majority of pre- school children referred to an otologist or a hearing clinic for a suspected hearing difficulty, are unable to cooperate sufficiently to insure a reliable pure-tone audiometric test. Even after pure tone results have been established with children in this age group, the tester frequently may be in doubt as to the validity of the results. The reasons for failure to get reliable results with young children appear to be these:

Speech reception threshold (SRT) tools have been developed to assist in the evaluation of hearing. This study was performed to develop, digitally record, evaluate, and equate Taiwan Mandarin trisyllabic words which can be used to measure the SRT. Eighty-nine commonly used trisyllabic words were chosen and digitally recorded by native male and female speakers. The words were then presented to 20 normally hearing subjects at 14 intensity levels (-10 to 16 dB HL) with 2 dB increments. Psychometric function slopes were calculated using logistic regression. Twenty-eight words with steep psychometric function were selected and digitally adjusted to match the mean subject pure-tone average (5.0 dB HL). A list of 28 trisyllabic words which were relatively homogeneous in audibility and slope were developed. The mean slopes for the 28 selected male and female trisyllabic Taiwan Madarin words were 11.3 %/dB (male talker) and 11.7 %/dB (female talker), respectively. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc.

Speech recognition thresholds are used for several clinical purposes, so it is important that they be accurate reflections of hearing ability. Variations in the acoustic signal may artificially decrease threshold scores, and such variations can result from being tested in a second dialect. Thirty-two native Mandarin-speaking subjects (sixteen from mainland China and sixteen from Taiwan) participated in speech recognition threshold testing in both dialects to see whether using non-native dialect test materials resulted in a significantly lower score. In addition, tests were scored by two interpreters, one from each dialect, to see whether the scorer's dialect resulted in a significantly different score. Talker dialect was found to be statistically significant, while scorer dialect was not. Factors explaining these findings, as well as clinical implications, are discussed.

The purpose of this study was to develop, digitally record, evaluate, and psychometrically equate a set of Tongan bisyllabic word lists for use in measurement of word recognition testing. Commonly used bisyllabic words were digitally recorded by male and female native talkers of Tongan. The psychometric performance of the words was measured at ten intensity levels (- 5 to 40 dB HL) in 5 dB increments by 20 listeners with normal hearing acuity. The 200 words with the highest rate of listener identification were included in four relatively psychometrically equivalent word lists of 50 words each and eight half-lists of 25 words each. Using logistic regression, the mean psychometric slope across the created word lists at 50% intelligibility was found to be 6.3%/dB for materials created from the male talker recordings and 6.2%/dB for the female talker recordings. To increase auditory homogeneity of the word recognition lists, the intensity of words in each list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists. Digital recordings of the psychometrically equivalent word recognition lists are available on compact disc.

Hearing can be evaluated through the presentation of tones or speech. Speech audiometry determines an individual's speech recognition threshold and word recognition score. Traditionally these materials were developed using familiar, frequently used, monosyllabic words. Currently, there are various types of word recognition materials including those which use word lists, short half-lists, and materials which use sentences level stimuli with competing noise. Word recognition materials were first developed in Standard American English; today, materials are now readily available in many other languages. When possible, word recognition materials are developed digitally to standardize their presentation. Currently, no recorded word recognition materials are commercially available for native speakers of Samoan. Bisyllablic words were chosen, rated, recorded, and prepared for subject testing. All subjects were native speakers of Samoan with adequate hearing, meeting required standards for audiological research. Results indicated that no significant differences were found among bisyllabic word lists or half-lists developed in the current study. Subject word recognition performance and psychometric function slopes were comparable to the results of other related studies. All materials were recorded onto CD and made commercially available. It is hoped that this resource will aid trained professionals in the diagnosis and remediation of hearing loss in Samoan-speaking individuals.

Despite the documented need for reliable speech audiometry materials for measures such as speech recognition threshold and word recognition score, such recorded materials are not available in the Vietnamese language. The purpose of this study was to develop, digitally record, evaluate, and psychometrically equate a set of Vietnamese bisyllabic and monosyllabic word lists for use in the measurement of speech recognition and word recognition ability, respectively. To create the speech recognition threshold materials, common Vietnamese bisyllabic words were digitally recorded by male and female talkers of Vietnamese and presented for evaluation to 20 native speakers of Vietnamese with normal hearing. Based on listener response, a set of 48 bisyllabic words with relatively steep psychometric function slopes were selected and digitally adjusted to ensure equivalency for psychometric function slope and to equate threshold to the mean pure-tone average for the test participants. To create the word recognition materials, 250 words were digitally recorded by one male and one female talker of Vietnamese and presented to the listeners for evaluation. Based on listener response, 200 words were selected and divided into 4 lists of 50 monosyllabic words and 8 half-lists of 25 monosyllabic words. The lists were digitally adjusted to ensure intensity threshold equivalency. The resulting mean psychometric function slopes at 50% for the speech recognition threshold materials is 11.3%/dB for the male talker and 10.2%/dB for the female talker. Analysis of the word recognition materials indicates no significant difference between the lists or half-lists. The mean psychometric function slope at 50% for the monosyllabic lists and half-lists is 5.1%/dB for the male recordings and 5.2%/dB for the female recordings. The results of the current study are comparable to those found in other languages. Digital recordings of the bisyllabic and monosyllabic word lists are available on compact disc.

O diagnóstico precoce da perda auditiva tem sido cada vez mais freqüente em virtude dos programas de saúde auditiva que estão sendo implantados em todo o país. Existe, contudo, a necessidade de técnicas e procedimentos que ajudem a identificar, com maior precisão, a presença e o grau da mesma. A Resposta Auditiva de Estado Estável (RAEE) é um procedimento eletrofisiológico que, ao contrário do Potencial Evocado Auditivo de Tronco Encefálico (PEATE) realizado com estímulo tone burst, possibilita avaliar, ao mesmo tempo limiares auditivos com especificidade por freqüência e por orelha, reduzindo assim o tempo do exame. Além disso, ele permite a estimulação até níveis próximos a 130 dBHL, podendo assim medir a audição residual. O objetivo deste estudo foi verificar a aplicabilidade da RAEE para determinar os limiares auditivos nos diferentes graus de perda auditiva neurossensorial. Foram avaliados 65 indivíduos com perda auditiva neurossensorial, sendo que 48 apresentaram alteração neurossensorial (coclear) de grau leve até profundo, e idades entre sete e 30 anos; e 17 apresentaram alteração neurossensorial (Neuropatia Auditiva/Dessincronia Auditiva) e idades entre 0,6 e cinco anos. A avaliação foi composta por Audiometria Tonal Liminar (ATL) e pesquisa da RAEE para o grupo com alteração neurossensorial (coclear) e somente a pesquisa da RAEE para o grupo com alteração neurossensorial (NA/DA). Os resultados demonstraram que, nos indivíduos com perda auditiva neurossensorial (coclear), houve associação significante (p<0,01) entre os limiares obtidos na ATL e RAEE para as freqüências de 0,5 a 4 kHz, ocorrendo uma maior concordância para graus de deficiências auditivas mais acentuadas. Já na perda auditiva neurossensorial (NA/DA), a RAEE mostrou ausência de resposta na maioria dos indivíduos avaliados. Concluímos que a RAEE pode predizer os limiares da ATL com maior precisão para os graus de perda auditiva mais acentuados, e que a utilização deste procedimento não mostrou informações adicionais que podem contribuir para o diagnóstico da perda auditiva neurossensorial (NA/DA). / The diagnosis of hearing loss in the first months of life has been increasingly frequent due to hearing health programs established throughout the country. Thus, techniques and procedures should be developed for accurate identification of the presence and severity of hearing loss, in a population whose motor and cognitive development does not allow response to behavioral methods. The auditory steady state response (ASSR) is an electrophysiological procedure which, different from the brainstem evoked response audiometry (BERA) conducted with tone burst stimuli, allows the establishment of hearing thresholds at multiple frequencies and for both ears, thus reducing the examination time. Moreover, it allows measurement of residual hearing due to the possibility of stimulation at levels close to 130 dBHL. Therefore, the present study aimed to investigate the applicability of ASSR for establishment of hearing thresholds in different severities of sensorineural hearing loss. A total of 65 individuals with sensorineural hearing loss were evaluated, among whom 48 presented mild to deep sensorineural disorder (cochlear), at the age range 7 to 30 years; and 17 presented sensorineural disorder (neuropathy/hearing dyssynchrony) aged 0.6 to 5 years. The evaluation comprised pure-tone threshold audiometry (PTTA) and ASSR analysis for the group with deep sensorineural disorder (cochlear) and only ASSR analysis for the group with sensorineural disorder (neuropathy/hearing dyssynchrony). The results demonstrated that, for individuals with deep sensorineural hearing loss (cochlear), there was significant association (p<0.01) between the thresholds obtained by PTTA and ASSR at frequencies from 0.5 to 4 kHz, with higher agreement in cases with more severe hearing loss. On the other hand, for the sensorineural hearing loss (neuropathy/hearing dyssynchrony), the ASSR was absent in most individuals analyzed. It was concluded that there is significant association between the thresholds obtained by PTTA and ASSR, and that the utilization of this procedure did not provide additional information that might contribute to the diagnosis of sensorineural hearing loss (neuropathy/hearing dyssynchrony), when compared to BERA

O diagnóstico precoce da perda auditiva tem sido cada vez mais freqüente em virtude dos programas de saúde auditiva que estão sendo implantados em todo o país. Existe, contudo, a necessidade de técnicas e procedimentos que ajudem a identificar, com maior precisão, a presença e o grau da mesma. A Resposta Auditiva de Estado Estável (RAEE) é um procedimento eletrofisiológico que, ao contrário do Potencial Evocado Auditivo de Tronco Encefálico (PEATE) realizado com estímulo tone burst, possibilita avaliar, ao mesmo tempo limiares auditivos com especificidade por freqüência e por orelha, reduzindo assim o tempo do exame. Além disso, ele permite a estimulação até níveis próximos a 130 dBHL, podendo assim medir a audição residual. O objetivo deste estudo foi verificar a aplicabilidade da RAEE para determinar os limiares auditivos nos diferentes graus de perda auditiva neurossensorial. Foram avaliados 65 indivíduos com perda auditiva neurossensorial, sendo que 48 apresentaram alteração neurossensorial (coclear) de grau leve até profundo, e idades entre sete e 30 anos; e 17 apresentaram alteração neurossensorial (Neuropatia Auditiva/Dessincronia Auditiva) e idades entre 0,6 e cinco anos. A avaliação foi composta por Audiometria Tonal Liminar (ATL) e pesquisa da RAEE para o grupo com alteração neurossensorial (coclear) e somente a pesquisa da RAEE para o grupo com alteração neurossensorial (NA/DA). Os resultados demonstraram que, nos indivíduos com perda auditiva neurossensorial (coclear), houve associação significante (p<0,01) entre os limiares obtidos na ATL e RAEE para as freqüências de 0,5 a 4 kHz, ocorrendo uma maior concordância para graus de deficiências auditivas mais acentuadas. Já na perda auditiva neurossensorial (NA/DA), a RAEE mostrou ausência de resposta na maioria dos indivíduos avaliados. Concluímos que a RAEE pode predizer os limiares da ATL com maior precisão para os graus de perda auditiva mais acentuados, e que a utilização deste procedimento não mostrou informações adicionais que podem contribuir para o diagnóstico da perda auditiva neurossensorial (NA/DA). / The diagnosis of hearing loss in the first months of life has been increasingly frequent due to hearing health programs established throughout the country. Thus, techniques and procedures should be developed for accurate identification of the presence and severity of hearing loss, in a population whose motor and cognitive development does not allow response to behavioral methods. The auditory steady state response (ASSR) is an electrophysiological procedure which, different from the brainstem evoked response audiometry (BERA) conducted with tone burst stimuli, allows the establishment of hearing thresholds at multiple frequencies and for both ears, thus reducing the examination time. Moreover, it allows measurement of residual hearing due to the possibility of stimulation at levels close to 130 dBHL. Therefore, the present study aimed to investigate the applicability of ASSR for establishment of hearing thresholds in different severities of sensorineural hearing loss. A total of 65 individuals with sensorineural hearing loss were evaluated, among whom 48 presented mild to deep sensorineural disorder (cochlear), at the age range 7 to 30 years; and 17 presented sensorineural disorder (neuropathy/hearing dyssynchrony) aged 0.6 to 5 years. The evaluation comprised pure-tone threshold audiometry (PTTA) and ASSR analysis for the group with deep sensorineural disorder (cochlear) and only ASSR analysis for the group with sensorineural disorder (neuropathy/hearing dyssynchrony). The results demonstrated that, for individuals with deep sensorineural hearing loss (cochlear), there was significant association (p<0.01) between the thresholds obtained by PTTA and ASSR at frequencies from 0.5 to 4 kHz, with higher agreement in cases with more severe hearing loss. On the other hand, for the sensorineural hearing loss (neuropathy/hearing dyssynchrony), the ASSR was absent in most individuals analyzed. It was concluded that there is significant association between the thresholds obtained by PTTA and ASSR, and that the utilization of this procedure did not provide additional information that might contribute to the diagnosis of sensorineural hearing loss (neuropathy/hearing dyssynchrony), when compared to BERA

THE DISSERTATION IS IN AFRIKAANS: The multi-linguistic and multi-cultural population of South Africa poses some unique challenges for valid and reliable service delivery by South African audiologists and acousticians, specifically when conducting valid and reliable speech audiometry evaluations. This is examined in the South African context, and set the base for the main aim of this study, namely the comparison of the ideal criteria for speech audiometry with the South African clinical practice of speech audiometry. Many variables can be identified in the course of the test stimuli and subsequent response when conducting speech audiometry. These variables can be divided into two categories, namely stimulus related variables (test content and test procedure) and test subject related variables. The variables are examined in light of the multi-linguistic and multi-cultural South African context, because of the challenges posed by this context to the South African audiologist. The study is conducted in three different phases, according to three sub aims. A thorough review of the subject literature was done to identify ideal criteria for speech audiometry. A questionnaire was sent to South African audiologists and acousticians, to examine the present clinical practice of speech audiometry in South Africa, and compare it to the criteria suggested in the literature in order to investigate the attainability of criteria and to identify problem areas. The results show low comparison regarding test content between the ideal criteria and South African clinical practice, especially because South African audiologists do not use a test battery consisting of different types of test material. Low comparison can be seen regarding the selection of test items, length of lists and degree of difficulty. Low comparison can also be seen with test procedure, mainly because audiologists rarely use pre-recorded test materials. High levels of comparison are found regarding presentation levels and test environment. With test subject variables, a discrepancy is also found between the ideal criteria and South African clinical practice, mainly because tests are not always conducted in the test subjects’ first language. By using the identified deficiencies in the clinical practice of speech audiometry in South Africa as a starting point, one can use further research to reach the ideal, namely the ideal criteria of conducting speech audiometry. The conclusions of this study can be used as suggestions for solutions for the unique problems that the practicing audiologist in South Africa has to deal with. The complexity of these problems will need further attention from researchers in this and other fields of study. / Dissertation (MCommunication Pathology)--University of Pretoria, 2007. / Speech-Language Pathology and Audiology / Unrestricted