The purpose of this study was to investigate the use of the SPAR test (Sensitivity Prediction by the Acoustic Reflex) on a sample of older adults who professed negative otologic histories. Twenty-seven subjects, ranging in age from sixty-four to eighty-three years of age (54 ears) were ultimately chosen as subjects. A young adult group, ranging in age from eighteen to thirty years of age, with normal audiometric hearing levels served as controls. Reflex threshold levels were obtained using 500 Hz., 1000 Hz., and 2000 Hz. pure tones and noise stimuli. Assessment of hearing loss was calculated on the difference between measures to ascertain hearing loss category and slope of loss according to a formula developed by Jerger (1974). The following conclusions were made on the basis of data collected in this investigation: The SPAR test was significant in assessing hearing sensitivity levels among the sample of geriatric subjects. The SPAR test was not statistically significant in assessing slope of loss in this sample of geriatric subjects. Reflex thresholds were consistently higher for aging than for a sample of young adults with normal hearing. This was true even among elderly subjects with average pure tone thresholds in the normal range. A significant portion of this carefully screened older adult sample displayed abnormal middle-ear function (as measured by tympanometry) in the absence of conventional audiometric indications of this. A significant portion of this older adult sample provided audiometric evidence of middle-ear pathology.

This study concerns audiometric evaluation and prediction of hearing loss in the autistic child based on information derived from acoustic reflex thresholds. Two groups (autistic males and normal children) of five subjects each were utilized. Results indicated that the acoustic reflex method consistently predicted significantly higher hearing thresholds for autistic subjects than operant pure-tone audiometric procedures. Furthermore, the acoustic reflex thresholds were significantly less sensitive in the autistic group than in the normal group, suggesting that the acoustic reflex response is somehow altered in autistic individuals. These findings are consistent with earlier work which hypothesized that autistics, manifest an organic brain lesion which interferes with the propagation of auditory information.

INTRODUÇÃO: O processamento da informação sonora depende da integridade das vias auditivas. O sistema auditivo eferente pode ser avaliado por meio de dois métodos objetivos e não-invasivos: a obtenção dos limiares dos reflexos acústicos, e a supressão das emissões otoacústicas. OBJETIVO: Verificar a atividade do sistema auditivo eferente, por meio da supressão das emissões otoacústicas por transientes (EOAT) e da sensibilização do reflexo acústico em indivíduos com alteração de processamento auditivo. MÉTODO: Foram avaliadas 50 crianças com alteração de processamento auditivo (grupo estudo) e 38 crianças sem alteração de processamento auditivo (grupo controle), por meio das EOAT evocadas por \"clicks\" na ausência e na presença de ruído ipsilateral e contralateral, e por \" tone bursts\", nas freqüências de 1000, 2000 e 4000 Hz na ausência e na presença de ruído contralateral, e de reflexo acústico nas freqüências de 500, 1000, 2000 e 4000 Hz na ausência e na presença de estímulo facilitador ipsi e contralateral. RESULTADOS: O valor da média de EOAT evocadas por \"clicks\" com estímulo supressor foi de até 1,50 dB para o grupo controle e de até 1,26 dB para o grupo estudo. Para as EOAT evocadas por \"tone bursts\" com estímulo supressor, os valores médios foram de até 2,69 dB para o grupo controle e de até 2,79 dB para o grupo estudo. Foi observado efeito de sensibilização do reflexo acústico com redução média de até 18,17 dB para o grupo estudo e de até 17,38 dB para o grupo controle. Não foi observada diferença estatisticamente significante entre as respostas do grupo controle e do grupo estudo, para supressão de EOAT (exceto na freqüência de 2000 Hz - \"tone burst\"), e para sensibilização do reflexo acústico. CONCLUSÕES: O grupo estudo apresentou valores reduzidos na pesquisa de supressão das EOAT e valores aumentados na sensibilização do reflexo acústico, em relação ao grupo controle. / INTRODUCTION: Auditory processing depends on the auditory pathways integrity. Efferent auditory system may be assessed in humans by two non-invasive and objective methods: acoustic reflex and otoacoustic emissions suppression. OBJECTIVE: Analyze efferent auditory system activity by otoacoustic emissions suppression and acoustic reflex sensitization in human subjects with auditory processing disorders. METHOD: Fifty children with auditory processing disorders (study group) and thirty-eight children without auditory processing disorders (control group) have being evaluated using clicks otoacoustic emission suppression with and without ipsilateral and contralateral white noise; tone bursts otoacoustic emission suppression in 1000, 2000 and 4000 Hz with and without contralateral white noise and acoustic reflex in 500, 1000, 2000 and 4000 Hz with and without ipsilateral and contralateral facilitator. RESULTS: The higher clicks otoacoustic emission suppression was up to 1.50 dB for the control group and up to 1.26 dB for the study group. The higher tone burst otoacoustic emission was up to 2.69 dB for the control group and up to 2.79 dB for the study group. The higher acoustical reflex sensitization was up to 18.17 dB for the study group and up to 17.38 dB for the control group. There was no significant statistical difference between results for control group and study group to otoacoustic emission suppression (except for 2000 Hz) and acoustical reflex sensitization. CONCLUSION: Study group presented smaller otoacoustic emission suppression than control group and study group presented higher acoustical reflex sensitization than control group.

Acoustic reflex thresholds (ARTs) are used clinically as a cross check for behavioral results and as a measure of 7th and 8th cranial nerve function. In clinical test batteries, ARTs are measured as a change in middle ear admittance of a pure tone probe in the presence of a pure tone or broadband noise (BBN) reflex activator. ARTs measured using a wideband probe may yield lower thresholds because the criterion change for 'present' reflexes can be observed across a range of frequencies rather than at a single frequency. ARTs were elicited in a group of 25 adults with normal hearing using a 226-Hz probe and a wideband (250 to 8000 Hz) probe, and activators of 500, 1000, and 2000-Hz and broadband noise (BBN). Wideband ARTs were estimated using an automated adaptive method. Lower mean ARTs were obtained for the wideband method compared to the clinical method by as much as 5-10 dB for tonal activators and 15 dB for BBN. Clinical benefits of lower ARTs include reduced activator levels during threshold estimation, and present rather than absent responses in some ears with absent ART using the clinical method. Results are encouraging for the automated adaptive ART procedure.

No description available.

INTRODUÇÃO: O processamento da informação sonora depende da integridade das vias auditivas. O sistema auditivo eferente pode ser avaliado por meio de dois métodos objetivos e não-invasivos: a obtenção dos limiares dos reflexos acústicos, e a supressão das emissões otoacústicas. OBJETIVO: Verificar a atividade do sistema auditivo eferente, por meio da supressão das emissões otoacústicas por transientes (EOAT) e da sensibilização do reflexo acústico em indivíduos com alteração de processamento auditivo. MÉTODO: Foram avaliadas 50 crianças com alteração de processamento auditivo (grupo estudo) e 38 crianças sem alteração de processamento auditivo (grupo controle), por meio das EOAT evocadas por \"clicks\" na ausência e na presença de ruído ipsilateral e contralateral, e por \" tone bursts\", nas freqüências de 1000, 2000 e 4000 Hz na ausência e na presença de ruído contralateral, e de reflexo acústico nas freqüências de 500, 1000, 2000 e 4000 Hz na ausência e na presença de estímulo facilitador ipsi e contralateral. RESULTADOS: O valor da média de EOAT evocadas por \"clicks\" com estímulo supressor foi de até 1,50 dB para o grupo controle e de até 1,26 dB para o grupo estudo. Para as EOAT evocadas por \"tone bursts\" com estímulo supressor, os valores médios foram de até 2,69 dB para o grupo controle e de até 2,79 dB para o grupo estudo. Foi observado efeito de sensibilização do reflexo acústico com redução média de até 18,17 dB para o grupo estudo e de até 17,38 dB para o grupo controle. Não foi observada diferença estatisticamente significante entre as respostas do grupo controle e do grupo estudo, para supressão de EOAT (exceto na freqüência de 2000 Hz - \"tone burst\"), e para sensibilização do reflexo acústico. CONCLUSÕES: O grupo estudo apresentou valores reduzidos na pesquisa de supressão das EOAT e valores aumentados na sensibilização do reflexo acústico, em relação ao grupo controle. / INTRODUCTION: Auditory processing depends on the auditory pathways integrity. Efferent auditory system may be assessed in humans by two non-invasive and objective methods: acoustic reflex and otoacoustic emissions suppression. OBJECTIVE: Analyze efferent auditory system activity by otoacoustic emissions suppression and acoustic reflex sensitization in human subjects with auditory processing disorders. METHOD: Fifty children with auditory processing disorders (study group) and thirty-eight children without auditory processing disorders (control group) have being evaluated using clicks otoacoustic emission suppression with and without ipsilateral and contralateral white noise; tone bursts otoacoustic emission suppression in 1000, 2000 and 4000 Hz with and without contralateral white noise and acoustic reflex in 500, 1000, 2000 and 4000 Hz with and without ipsilateral and contralateral facilitator. RESULTS: The higher clicks otoacoustic emission suppression was up to 1.50 dB for the control group and up to 1.26 dB for the study group. The higher tone burst otoacoustic emission was up to 2.69 dB for the control group and up to 2.79 dB for the study group. The higher acoustical reflex sensitization was up to 18.17 dB for the study group and up to 17.38 dB for the control group. There was no significant statistical difference between results for control group and study group to otoacoustic emission suppression (except for 2000 Hz) and acoustical reflex sensitization. CONCLUSION: Study group presented smaller otoacoustic emission suppression than control group and study group presented higher acoustical reflex sensitization than control group.

Rapid implementation of universal newborn hearing screening programs has exposed a need for a reliable test of middle ear function for timely identification of middle ear pathology and for differentiation between true sensorineural and conductive hearing losses. Use of higher probe tone frequencies for the assessment of immitance measures have proven to be more reliable and accurate in identifying MEE in infants. However a lack of classification-guidelines and age specific normative data exists. This study investigated the characteristics and normative values of high frequency tympanometric and acoustic reflex results for infants (n = 936 ears). Participants were 510 infants (262 male, 248 female) aged 0 – 12 months (mean age = 12.8 weeks) recruited from primary health care and immunization clinics in a South African community. A three-part procedure was performed on each test ear: 1) OAEs were recorded and pass results served as control variable for normal middle ear functioning; 2) 1000 Hz probe tone admittance, susceptance and conductance tympanograms were recorded and analysed in terms of shape, tympanometric peak pressure and maximum (peak) admittance; 3) 1000 Hz probe tone acoustic reflexes, measured with a 1000 Hz ipsilateral stimulus, were recorded and thresholds determined. Significant associations were observed between tympanogram shape, and OAE pass or fail results. 93% of ears with an OAE pass result displayed peaked tympanograms, while 79% of ears with absent OAE’s displayed flat tympanograms. Single peaked tympanograms were recorded in 782 ears (84%), double peaked tympanograms in 41 (4%) ears and flat sloping tympanograms in 112 (12%) ears. Admittance (Ya) tympanograms for the total sample displayed a mean admittance value of 2.9 mmho, with a standard deviation of 1.1 mmho. The 90th percent range was determined at 1.5 mmho (5th percentile) to 4.9 mmho (95th percentile). Mean tympanometric peak pressure in Ya tympanograms was 0.1 daPa, with a standard deviation of 61 daPa. The 90th percent range was -110 daPa to 90 daPa for the 5th and 95th percentiles respectively. Gender specific norms indicated a higher admittance for male ears. Age specific norms indicate a gradual increase in admittance indicating the need for age specific normative classification systems. Ipsilateral 1000 Hz stimuli acoustic reflex measurement proved successful with a 1000 Hz probe tone and present reflexes were recorded in 84% of ears tested. Significant association between acoustic reflex presence, OAE pass and peaked tympanogram results were observed. The normative tympanometric values derived from the cohort may serve as a guide for identification of middle ear effusion in neonates. High frequency tympanometry in combination with acoustic reflexes proves a useful measure for verifying middle ear functioning in young infants. / Dissertation (M (Communication Pathology))--University of Pretoria, 2006. / Speech-Language Pathology and Audiology / M (Communication Pathology) / unrestricted