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Objective To study the clinical significance of Chirp-ASSR and the characteristics of hearing loss patients by ASSR(auditory steady-state responses) under Chirp stimulation.Methods A total of 136 hearing loss children (5～10 years old) with 272 ears were distributed into four groups based on 500 Hz,1 000 Hz,2 000 Hz and 4 000 Hz auditory threshold arithmetic average:20～dB HL,40～dB HL,60～dB HL,and≥80 dB HL groups.To compare the correlation of the PTA and Chirp-ASSR in different frequencies domain through SPSS statistics 19.0 software,the data were used T-test and Pearson analysis.Results ①The group(≥80 dB HL) achieved a statistically significant higher reaction threshold than pure tone threshold.②The correlation index γ'of PTA and Chirp-ASSR showed a decline along with the hearing loss increase;It increased along with the test frequency,there was a significant difference between 500 Hz and 4 000 Hz(P＜0.05).Conclusion Chirp-ASSR is a frequency-specific electrophysiological test method,it could reflect the truthful listening ability,especially in mild,moderate,and severe hearing loss children.
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Introducción: Los potenciales evocados auditivos de estado estable (PEAEE) son respuestas cerebrales frente a estímulos auditivos continuos modulados en amplitud y/ o frecuencia (AM/FM). Este examen puede determinar objetivamente umbrales por frecuencia específica. Objetivo: Conocer el manejo y describir los resultados de la aplicación de los PEAEE en sujetos con distintos niveles auditivos. Material y método: Estudio exploratorio y transversal en sujetos de 10 a 30 años con audición normal o pérdida auditiva (55 oídos). El estímulo consistió en un tono puro (0,5, 1,2y4 kHz) a 46HzAM/FM. Resultados: Se obtuvo alta correlación entre la audiometría y PEAEE, tanto en el promedio (r =0,980) como en cada frecuencia evaluada. Los umbrales de PEAEE fueron superiores a los audiométricos y la diferencia promedio fue 23 dB HL en normoyentes y 13 dB HL en hipoacúsicos. Conclusiones: Los umbrales de PEAEE en sujetos hipoacúsicos fueron más cercanos a los audiométricos que en normoyentes. Dada la alta correlación entre la audiometría y PEAEE, éste podría incorporarse en la evaluación clínica, siendo un complemento en la detección y estudio de patologías auditivas.
Introduction: Auditory steady-state responses (ASSR) correspond to brain responses evoked by continuous auditory stimuli, modulated in amplitud and/or frequency (AM/FM). This test can objectively determined specific frequency thresholds. Aim: To understand the procedures and to describe the results of the ASSR test application on subjects with different auditory degrees. Material and method: Exploratory and transversal study in 10-to-30-years subjects with normal hearing or hearing loss (55 ears). The stimuli were pure tones (0.5, 1, 2y4 kHz) at 46-Hz AM/FM. Results: A high correlation coefficient was obtained between audiometry and the ASSR as well in the average (r =0.980) as in each evaluated frequency. The ASSR thresholds presented higher values than the audiometrical thresholds. The average difference were 23 dB HL in normally hearing subjects and 13 dB HL in hearing-impaired subjects. Conclusion: The ASSR threshold in the hearing-impaired group were closer to the audiometrical thresholds than in the normally hearing group. Due to the high correlation between audiometry and ASSR, it can be considered its incorporation in the clinical evaluation, bestowing a complementary value in the detection of auditory pathologies.
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Humans , Male , Female , Child , Adolescent , Adult , Hearing/physiology , Evoked Potentials, Auditory/physiology , Auditory Threshold/physiology , Audiometry, Pure-Tone , Cross-Sectional Studies , Hearing Loss/physiopathologyABSTRACT
Objective To investigate the correlation between auditory steady state responses(ASSR)and click audiotory brainstem respone(cABR)of infants as a function of different ages below 36 months.Methods 299 infants(497 ears from 1 to 36 months)were divided into 5 groups:208 ears in group 1(1~ month old),81 ears in group 2(4~ months old),47 ears in group 3(7~ months old),53 ears in group 4(13~ months old),and 108 ears in group 5(19~36 months old).The correlation analysis of the thresholds of 2 kHz and 4 kHz between ABR and ASSR were conducted,respectively with SPSS.Results In group 1,the correlation coefficient at 2 kHz between ABR and ASSR was 0.499,the correlation coefficient at 4 kHz between ABR and ASSR was 0.541,the correlation coefficient of the means of 2 kHz and 4 kHz between ABR and ASSR was 0.531.In group 2,these three correlation coefficients were 0.678,0.705 and 0.726,for group 3,0.792,0.717 and 0.777;for group 4,0.934,0.880 and 0.915,for group 5,0.817,0.810 and 0.867.Conclusion For infants of 1~18 months old,the correlation between ABR and ASSR increases as a function of ages.
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Objective To explore some characters of auditory steady-state responses (ASSR) to multiple simultaneous stimuli in a sample of normal-hearing adults.Methods The ASSR to multiple simultaneous stimuli were recorded in a sample of 32 normal-hearing adults (64 ears). Simultaneous carrier tones (0.5, 1, 2 and 4 kHz), modulated in amplitude at different rate of 77, 85,93, 101 Hz for left ear and 79, 87, 95, 103 Hz for right ear, were presented binaurally by the insert phones. For each subject the response thresholds (RTHs) at 0.5, 1, 2 and 4 kHz were determined automatically and compared with the corresponding behavioral thresholds (BTHs).Results ①In the normal-hearing adults, RTHs were on average between 7～19 dB above the BTHs.②2-way repeated measures ANOVA (ear?carrier frequencies) showed significant main effect between carrier frequencies on RTH ( F =31.254; ? 3,179; P =0.000). Post Hoc analysis indicated that this effect was due to the highest threshold found at 0.5 kHz. The test showed no significant difference of threshold between left ear and right ear ( F =1.942; ? 1,179; P =0.165). ③Taking 60 dB SPL as analysis level, 2-way repeated measures ANOVA (gender?carrier frequencies) revealed significant difference of amplitude between male and female( F =16.490; ? 1,175; P =0.000); and difference of amplitude between carrier frequencies ( F =2.948; ?3, 175; P =0.034).④The average testing time was 61 minutes for male and 69 minutes for female. Independent t-test showed statistical significance within sex.⑤Two- way ANOVA (state?frequency)showed that background EEG noise were significantly higher in awake than that in sleep ( F =152.511; P =0.000). There were no appreciable significance in background noise among frequencies. Conclusion The ASSR to multiple simultaneous stimuli was proven to be a frequency specific, objective and valid technique for threshold estimation at least for normal-hearing adults. Issues concern ing clinical use were discussed.
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0.05).②For the neonates passed DPOAE screening,the ASSR thresholds at 250,500 and 1 000 Hz and the ABR thresholds were not correlated,but there were significant correlations at 2 000 and 4 000 Hz.For the neonates whose DPOAE screening results were abnormal,the ASSR thresholds and the ABR thresholds were significantly correlated at all the carrier frequencies.Conclusion Reliable and frequency specific results could be obtained by ASSR,so it could be a promising audiometry to evaluate the hearing of neonates.