Comparison of ASSR, ABR and 40 Hz AERP Response Thresholds at Different Frequencies and Their Forensic Applications / 法医学杂志

OBJECTIVES@#To explore the relationship between the frequency characteristics and response threshold of auditory steady-state response (ASSR), auditory brainstem response (ABR) and 40 Hz auditory event related potential (40 Hz AERP), and their application values in forensic medicine.@*METHODS@#Thirty volunteers with normal hearing (60 ears) were selected to perform pure tone audiometry (PTA) threshold and ASSR, ABR and 40 Hz AERP response threshold tests in the standard sound insulation shielding room, and the results were statistically analyzed by SPSS 22.0 software.@*RESULTS@#At 0.5 kHz and 1.0 kHz frequencies, the correlation between 40 Hz AERP response threshold and PTA threshold was good, which was better than that of ASSR and ABR response threshold. At 2.0 kHz and 4.0 kHz frequencies, the correlation between ASSR and ABR response thresholds and PTA threshold was good, which was better than that of 40 Hz AERP response threshold.@*CONCLUSIONS@#To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.

Gamma-Band Auditory Steady-State Responses and Psychopathology / 대한정신약물학회지

Gamma band neural oscillations in the human electroencephalogram (EEG) play an important role in perceptual and cognitive processes. Auditory steady state responses (ASSR) can probe neural oscillations with respect to phase synchronization and response magnitude. EEG recordings in bipolar disorder and schizophrenia patients showed reduced evoked power and phase locking for 40 Hz ASSR. Also, several studies have reported increased evoked power and decreased synchronization of the gamma band in patients with Alzheimer's disease. ASSR deficits in various psychiatric disorders may index disturbances of gamma-aminobutyric acid neurotransmission within auditory pathways and cortex. Although, several studies have reported ASSR deficits in various psychopathologies of psychiatric illness, further studies are necessary that investigate biological mechanism based on the ASSRs. In this review, the current concept and biological mechanism of ASSRs are discussed.

Audiologic Comprehensive Evaluation of Sensorineural Deafness in Children / 听力学及言语疾病杂志

Objective To study the clinical application of the complete audiologic evaluation battery consisting of ABR,ASSR and behavioral audiometry in sound field for the identification of sensorineural losses in children.Methods In the study 48 children were divided as group PTA of the children assessed by pure tone audiometry and ABR and ASSR test,and group BA of the children unable to perform on behavioral evaluations.Results The analysis of the audiometric results of group PTA showed significant correlation between the ASSR thresholds and pure tone thresholds(P＜0.01) at various frequencies.The correlation coefficients were 0.75,0.76,0.76,and 0.83 at different frequencies.The ASSR-PTA linear regression was utilized.The comparison of the ABR and ASSR results of group BA indicated that 23 ears responded in ASSR but without responses in ABR.Those without ASSR responses also had no ABR There were 116 tests in total four frequencies for the 29 ears.83 responses were obtained from ASSR,89 responses from behavior audiometry and 96 from the use of the both tests.Conclusion The comprehensive audiologic evaluation battery could be used to test younger children with severe heating loss children as compared to the pure tone audiometry alone.More detailed data can be obtained thus from children to assist in rehabilitation in a more effective mariner.

Aplicación de potenciales evocados de estado estable como examen auditivo en una población de jóvenes con diferentes niveles de audición / Application of evoked steady-state responses as auditory test on subjects with different auditory degrees

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.

Aplicabilidade da resposta auditiva de estado estável em campo livre na avaliação de bebês e crianças usuárias de próteses auditivas / Applicability of the free-field steady-state auditory response in the assessment of infants and children using hearing aids

Introdução: A resposta auditiva de estado estável (RAEE) pode ser captada utilizando vários tipos de transdutores como fones supra-aurais, fones de inserção, vibrador ósseo e alto falante. A avaliação por meio de alto falante pode ser utilizada na determinação dos níveis mínimos de resposta em campo livre com e sem próteses auditivas. Objetivo: avaliar a aplicabilidade da RAEE em campo livre segundo a saída máxima do transdutor e tempo de exame. Métodos: Foram avaliadas 27 crianças com perda auditiva neurossensorial bilateral de grau moderado a profundo com faixa etária entre oito meses e 12 anos por meio da audiometria tonal e RAEE em campo livre, com e sem as próteses auditivas. Resultados: Na condição sem prótese auditiva, a presença de respostas na audiometria foi maior que na RAEE. Na condição com prótese auditiva, a presença de respostas na audiometria e na RAEE foi igual para as freqüências de 1000, 2000 e 4000 Hz. Não foi observada associação entre o tempo de exame e idade. O menor tempo médio de exame foi observado na perda auditiva de grau profundo, na condição sem prótese auditiva. Conclusões: Na condição com prótese auditiva, a presença de resposta tende a 100 % em ambos os procedimentos de avaliação nas diferentes freqüências. Não há associação entre o tempo de exame e variável idade. O tempo de exame nas crianças com perda auditiva de grau moderado e severo é maior do que no grau profundo, na condição sem prótese auditiva. Na condição com prótese auditiva, não há associação entre tempo de exame e o grau da perda auditiva.

Introduction : The auditory steady-state response (ASSR) can be recorded by the utilization of many kinds of transductors as supra-auricular phones, insertion phones, bone vibrator and loudspeaker. The assessment by loudspeaker may be used on the determination of minimal answer levels in free field with or without hearing aids. Objective : to evaluate the applicability of ASSR in free field according to maximum output of the transductor and the duration of the exam. Methods: 27 children aged from 8 months to 12 years, with bilateral neurossensorial hearing impairment from moderate to profound were evaluated by means of tonal audiometry and ASSR on soundfield with and without hearing aids. Results: In the condition without hearing aids, the answers presence in audiometry and ASSR was the same for frequencies of 1000, 2000 and 4000 Hz. No association was observed between the duration of the exam and age. The smallest time of duration of exam was observed with hearing impairment of profound degree, in the condition without hearing aid. Conclusions: In the condition with hearing aids, the answer presence tends towards 100% on both evaluation procedures on different frequencies. There is no association between duration of ASSR exam and age. The duration of the ASSR exam on children with moderate and severe hearing impairment is higher than with profound degree in condition without hearing aids. In the condition with hearing aids there is no association between duration of ASSR exam and hearing impairment degree.

Introduccion: La respuesta auditiva de estado estable (RAEE) se puede captar utilizando vários tipos de transdutores como auriculares supra-aurales, auriculares de inserción, vibrador oseo y altavoz. La evaluació por médio de altavoz puede ser usada para la derterminacíon de niveles mínimos de respuesta en campo libre con y sin audífonos. Objetivo: evaluar la aplicabildad de RAEE en campo libre de acuerdo con la salida máxima del transdutor y el tiempo de examen. Métodos: Se han evaluado 27 niños con perdida auditiva neurosensorial bilateral de grado moderado a profundo con edades entre ocho meses y 12 años por médio de la audiometria tonal y RAEE en compo libre con y sin audifonos. Resultados: En la condición sin uso de audifonos la presencia de respuesta en la audiometria fue maior que en la RAEE. En la condición con audifonos la presencia de respuestas en la audiomentria y en la RAEE fue igual para las frecuencias de 1000, 2000 y 4000 Hz. No se observó associación entre el tiempo de examen y la edad. El tiempo médio mas corto de examen fué observado para perdida de grado profundo, en la condición sin uso de audifono. Conclusión: En la condición con audifono la presencia de respuestas tiende a 100% en ambos procediemientos de evaluación en las diferentes frecuencias. No hay asociación entre tiempo de examen y la variable edad. El tiempo médio de examen para niños con perdida auditiva moderada y severa es maior que para niños con perdida profunda en la condición sin audifono. En la condición con audifono no hay asociación entre tiempo de examen y grado de perdida auditiva.

The Application of Auditory Steady - State Responses to the Neonates Hearing Evaluation / 听力学及言语疾病杂志

Objective To explore the use of auditory steady-state response (ASSR) for threshold evaluation in neonates. Methods 30 neonates 60 ears) were included in the study who passed distortion product otoacoustic emission (DPOAE) screening and 45 neonates (78 ears) who failed DPOAE. The ASSR thresholds were evaluated screening, the significant difference was found between the ASSR thresholds at 250 Hz and the ABR thresholds (P ＜0.05), however the ASSR thresholds at 4 000 Hz and average thresholds were not different from the ABR thresholds (P＞0.05). For the neonates whose DPOAE screening results were abnormal, the ASSR thresholds from 250 to 4 000 Hz and average thresholds were not significant different from the ABR thresholds respectively (P＞0.05). olds 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.

The Correlation between Auditory Brainstem Responses and Auditory Steady State Responses of Infants as a Function of Ages / 听力学及言语疾病杂志

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.

Extraction method of 40Hz ASSR for monitoring the depth of anaesthesia / 医疗卫生装备

In recent years, 40Hz auditory steady state response (ASSR) has been paid more attention when the depth of anaesthesia monitored because its same source with the middle latency auditory evoked potential (MLAEP), strong anti-jamming ability and close relationship with consciousness level. This article brings forward some effective and steady methods for extracting ASSR according to its characteristics. The results of these methods are analyzed and compared based on the actual records from clinical practice. And thus an extraction method fit for monitoring the depth of anaesthesia is determined.

The Application of Auditory Steady-State Responses to the Neonates Hearing Evaluation / 听力学及言语疾病杂志

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.

The application of the extraction of 40Hz ASSR with parametric-model method to monitoring the depth of anesthesia / 医疗卫生装备

It is very significative to perform real-time and effective monitor of the depth of anesthesia during the clinical operation. With the introduction of muscle-relaxing agents in general anesthesia, the two major indices to judge the depth of anesthesia have been obscured, which makes it more difficult to judge the depth of anesthesia. In recent years it has been found that 40Hz Auditory Steady State Response (ASSR) has a very good characteristic to monitor the depth of anesthesia. This article makes use of parametric-model method to extract 40Hz ASSR, which has a higher speed than Moving Time Average (MTA) when tracing the transition process of the patient from being conscious to being unconscious.