Corticostriatal Neurons in the Anterior Auditory Field Regulate Frequency Discrimination Behavior / 神经科学通报·英文版

The anterior auditory field (AAF) is a core region of the auditory cortex and plays a vital role in discrimination tasks. However, the role of the AAF corticostriatal neurons in frequency discrimination remains unclear. Here, we used c-Fos staining, fiber photometry recording, and pharmacogenetic manipulation to investigate the function of the AAF corticostriatal neurons in a frequency discrimination task. c-Fos staining and fiber photometry recording revealed that the activity of AAF pyramidal neurons was significantly elevated during the frequency discrimination task. Pharmacogenetic inhibition of AAF pyramidal neurons significantly impaired frequency discrimination. In addition, histological results revealed that AAF pyramidal neurons send strong projections to the striatum. Moreover, pharmacogenetic suppression of the striatal projections from pyramidal neurons in the AAF significantly disrupted the frequency discrimination. Collectively, our findings show that AAF pyramidal neurons, particularly the AAF-striatum projections, play a crucial role in frequency discrimination behavior.

The function of auditory cortex in the elderly using functional near-infrared spectroscopy technology / 中华耳鼻咽喉头颈外科杂志

Objective: Functional near-infrared spectroscopy (fNIRS) was used to study the effect of aging on the neuroimaging characteristics of cerebral cortex in the process of speech perception. Method: Thirty-four adults with normal hearing were recruited from March 2021 to June 2021, including 17 in the young group, with 6 males, 11 females, age (32.1±5.0) years, age range 20-39 years. and 17 in the elderly group, with 6 males, 11 females, age (63.2±2.8) years, age range 60-70 years. The test material was the sentence table of the Mandarin Hearing Test in Noise (MHINT). The task state block experiment design was adopted, and the temporal lobe, Broca's area, Wernicke's area, motor cortex were used as regions of interest. Objective brain imaging technology (fNIRS) combined with subjective psychophysical testing method was used to analyze the activation area and degree of cerebral cortex related to auditory speech perception in the elderly and young people under different listening conditions (quiet, signal-to-noise ratio of 10 dB, 5 dB, 0 dB, -5 dB). SPSS 23 software was used for statistical analysis. Result: The activation area and degree of activation in the elderly group were lower than those in the young group under each task condition; The number of activation channels in the young group were significantly more than those in the old group, and the number of activation channels in the left hemisphere were more than those in the right hemisphere, but there was no difference in the number of activation channels. There were more channels affected by age in the left hemisphere than in the right hemisphere. The activation degree of the young group when the signal-to-noise ratio was 0 dB was significantly higher than that of other signal-to-noise ratio conditions (P<0.05), but there was no significant difference in the old group under the five conditions (P>0.05). The speech recognition score of the young group was higher than that of the old group under all conditions. When the quiet and signal-to-noise ratio was 10 dB, the correct score of the two groups was equal or close to 100%. With the gradual decrease of signal-to-noise ratio, there was a significant difference between the two groups when the signal-to-noise ratio was 5 dB. The speech recognition accuracy of the young group decreased significantly when the signal-to-noise ratio was 0 dB, while that of the old group decreased significantly when the signal-to-noise ratio was 5 dB. Conclusions: With the increase of age, the speech perception in noisy environment and the activity of cerebral cortex gradually deteriorate, and the speech dominance hemisphere (left hemisphere) will be significantly affected by aging. The overall activation area and activation degree of the elderly under different speech tasks are lower than those of the young.

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.

Relative contributions of auditory and cognitive functions on speech recognition in quiet and in noise among older adults / Contribuições relativas das funções auditivas e cognitivas no reconhecimento da fala no silêncio e no ruído entre idosos

Abstract Introduction: Hearing acuity, central auditory processing and cognition contribute to the speech recognition difficulty experienced by older adults. Therefore, quantifying the contribution of these factors on speech recognition problem is important in order to formulate a holistic and effective rehabilitation. Objective: To examine the relative contributions of auditory functioning and cognition status to speech recognition in quiet and in noise. Methods: We measured speech recognition in quiet and in composite noise using the Malay Hearing in noise test on 72 native Malay speakers (60-82 years) older adults with normal to mild hearing loss. Auditory function included pure tone audiogram, gaps-in-noise, and dichotic digit tests. Cognitive function was assessed using the Malay Montreal cognitive assessment. Results: Linear regression analyses using backward elimination technique revealed that had the better ear four frequency average (0.5-4 kHz) (4FA), high frequency average and Malay Montreal cognitive assessment attributed to speech perception in quiet (total r2 = 0.499). On the other hand, high frequency average, Malay Montreal cognitive assessment and dichotic digit tests contributed significantly to speech recognition in noise (total r2 = 0.307). Whereas the better ear high frequency average primarily measured the speech recognition in quiet, the speech recognition in noise was mainly measured by cognitive function. Conclusions: These findings highlight the fact that besides hearing sensitivity, cognition plays an important role in speech recognition ability among older adults, especially in noisy environments. Therefore, in addition to hearing aids, rehabilitation, which trains cognition, may have a role in improving speech recognition in noise ability of older adults.

Resumo Introdução: A alteração da acuidade auditiva, do processamento auditivo central e da cognição são fatores que contribuem para a dificuldade de reconhecimento da fala em idosos. Portanto, quantificar a contribuição desses fatores no problema de reconhecimento da fala é importante para a formulação de uma reabilitação holística e efetiva. Objetivo: Examinar as contribuições relativas do funcionamento auditivo e do estado cognitivo para o reconhecimento da fala no silêncio e no ruído. Método: Nós medimos o reconhecimento de fala no silêncio e no ruído composto com o teste Malay hearing in noise test em 72 idosos malaios nativos falantes (60-82 anos) com audição normal a perda auditiva de grau leve. A avaliação da função auditiva incluiu audiograma de tons puros, teste gaps-in-noise e testes dicótico de dígitos. A função cognitiva foi avaliada pelo teste Malay Montreal cognitive assessment. Resultados: Análises de regressão linear com técnicas de eliminação backward na orelha melhor revelaram média de quatro frequências (0,5-4 kHz) (4AF), média de alta frequência e teste Malay Montreal cognitive assessment na orelha melhor, mensurada pela percepção da fala no silêncio (r2 total = 0,499). Por outro lado, a média de alta frequência, Malay Montreal cognitive assessment e o teste dicótico de dígitos contribuíram significativamente para o reconhecimento da fala no ruído (r2 total = 0,307). Enquanto a média de alta frequência da melhor orelha mediu principalmente o reconhecimento da fala no silêncio, o reconhecimento da fala no ruído foi mensurado principalmente pela função cognitiva. Conclusões: Esses achados destacam o fato de que, além da sensibilidade auditiva, a cognição desempenha um papel importante na capacidade de reconhecimento da fala em idosos, principalmente em ambientes ruidosos. Portanto, além de aparelhos auditivos, a reabilitação, que treina a cognição, pode ter um papel na melhoria da capacidade do reconhecimento da fala no ruído entre os idosos.

Brainstem auditory evoked potentials with speech stimulus in neonates / Potenciais evocados auditivos de tronco encefálico por estímulo de fala em neonatos

Abstract Introduction: Brainstem auditory evoked potentials in response to complex sounds, such as speech sounds, investigate the neural representation of these sounds at subcortical levels, and faithfully reflect the stimulus characteristics. However, there are few studies that utilize this type of stimulus; for it to be used in clinical practice it is necessary to establish standards of normality through studies performed in different populations. Objective: To analyze the latencies and amplitudes of the waves obtained from the tracings of brainstem auditory evoked potentials using speech stimuli in Brazilian neonates with normal hearing and without auditory risk factors. Methods: 21 neonates with a mean age of 9 days without risk of hearing loss and with normal results at the neonatal hearing screening were evaluated according to the Joint Committee on Infant Hearing protocols. Auditory evoked potentials were performed with speech stimuli (/da/ syllable) at the intensity of 80 dBNA and the latency and amplitude of the waves obtained were analyzed. Results: In the transient portion, we observed a 100% response rate for all analyzable waves (Wave I, Wave III, Wave V and Wave A), and these waves exhibited a latency <10 ms. In the sustained portion, Wave B was identified in 53.12% of subjects; Wave C in 75%; Wave D in 90.62%; Wave E in 96.87%; Wave F in 87.5% and Wave O was identified in 87.5% of subjects. The observed latency of these waves ranged from 11.51 ms to 52.16 ms. Greater similarity was observed for the response latencies, as well as greater amplitude variation in the studied group. Conclusions: Although the wave morphology obtained for brainstem evoked potentials with speech stimulation in neonates is quite similar to that of adults, a longer latency and greater variation in amplitude were observed in the waves analyzed.

Resumo Introdução: Os potenciais evocados auditivos de tronco encefálico para sons complexos, como, por exemplo, sons de fala, investigam a representação neural desses sons em níveis subcorticais e refletem com fidelidade as características do estímulo. No entanto, existem ainda poucos estudos que usam esse tipo de estímulo e para que possa ser usado na prática clínica é necessário estabelecer padrões de normalidade por meio de estudos em diferentes populações. Objetivo: Analisar as latências e as amplitudes das ondas obtidas nos traçados dos potenciais evocados auditivos de tronco encefálico por estímulo de fala em neonatos brasileiros com audição normal e sem risco auditivo. Método: Foram avaliados 21 neonatos com média de 9 dias, sem risco auditivo segundo o Joint Committe on Infant Hearing e com resultado normal para triagem auditiva neonatal. Fizeram-se potenciais evocados auditivos por estímulo de fala (sílaba /da/) na intensidade de 80 dBNA e analisaram-se a latência e a amplitude das ondas obtidas. Resultados: Na porção transiente observaram-se 100% de ocorrência de resposta para todas as ondas analisáveis (Onda I, Onda III, Onda V e Onda A) e esse conjunto de ondas apresentou latência inferior a 10 ms. Na porção sustentada a frequência de ocorrência da Onda B foi de 53,12%; da Onda C 75%; da Onda D 90,62%; da Onda E 96,87%; da Onda F 87,5% e da Onda O 87,5% e a latência observada dessas ondas variou de 11,51 ms a 52,16 ms. Observou-se maior similaridade nas latências das respostas e maior variação da amplitude no grupo estudado. Conclusões: Embora a morfologia das ondas obtidas para os potenciais evocados de tronco encefálico para o estímulo de fala em neonatos seja bastante semelhante às dos adultos, observou-se maior latência e maior variação da amplitude das ondas analisáveis.

Applicability of the real ear measurement for audiological intervention of tinnitus / Aplicabilidade das medidas da orelha real na intervenção audiológica do zumbido

Abstract Introduction Tinnitus is present in a large part of chronic health complaints, and it is considered a public health problem injurious to the individual's quality of life. Considering the increase of the world population associated with an increase of life expectancy, tinnitus remains a cause for medical concern, since during aging the occurrence of auditory impairments due to the deterioration of the peripheral auditory structures and central impairs the quality of life. Objective The aim of the present study was to analyze the applicability of real ear measurements for audiological intervention of tinnitus through specific evaluation, selection, verification and validation of the hearing aids combined with the sound generator. Methods Forty individuals of both genders with hearing loss and tinnitus complaints were deemed eligible to compose the sample. They were enrolled according to clinical symptoms and submitted to the following procedures: anamnesis and previous complaint history, high frequency audiometry, immittanciometry and acuphenometry with the research of psychoacoustic thresholds of pitch, loudness and minimum masking threshold, sound generator, in addition to the application of the Tinnitus Handicap Inventory and Visual Analog Scale tools. The entire sample was adapted with Siemens hearing aids and a sound generator, participated in a counseling session with support of digital material and evaluated in two situations: Initial Assessment (before the hearing aids and sound generator adaptation) and Final Assessment (6 months, after adaptation). The statistical analyzes were descriptive and inferential, adopted a significance level of 5% and the T-Paired Test and the Spearman Correlation test were performed. Results The results showed that there was a benefit with the use of hearing aids combined with a sound generator from the statistically significant values and strong correlations between the sound generator verification data regarding acuphenometry and the nuisance/severity questionnaires. Regarding the verification of the sound generator, it is important to highlight that the entire sample selected the effective acoustic stimulation based on the comfort levels, which was proved in the present study to be a sufficient intensity for positive prognosis, whereas the users' noises were found below the psychoacoustic thresholds of acuphenometry. Conclusion The present study concluded that the audiological intervention with any level of sound stimulus is enough to obtain a positive prognosis in the medium term. Data that specifies that the verification of sound generator was effective at the real ear measurements are important in the evaluation and intervention of the complaint. In addition, it points out that the greater the tinnitus perception, the greater its severity, and the greater the nuisance, the higher the psychoacoustics thresholds of frequency and the minimum threshold of masking.

Resumo Introdução O zumbido está presente em grande parte das queixas crônicas de saúde, é considerado um problema de saúde pública, prejudicial à qualidade de vida do indivíduo. Considerando o aumento da população mundial associado ao aumento da expectativa de vida, a tendência é que o zumbido permaneça como um motivo de preocupação, uma vez que com a idade a ocorrência de prejuízos auditivos decorrentes da deterioração das estruturas auditivas periféricas e centrais ocasiona grande impacto negativo na qualidade de vida. Objetivo Analisar a aplicabilidade das medidas da orelha real para a intervenção audiológica do zumbido através de avaliação específica, seleção, verificação e validação do aparelho de amplificação sonora individual combinada ao gerador de som. Método Quarenta indivíduos de ambos os sexos com perda auditiva e queixa de zumbido foram considerados elegíveis para compor a amostra. Eles foram atendidos conforme a demanda clínica e submetidos aos seguintes procedimentos: anamnese e história pregressa da queixa, audiometria de alta frequência, imitanciometria e acufenometria com pesquisa dos limiares psicoacústicos de pitch, loudness e limiar mínimo de mascaramento, gerador de som, além da aplicação das ferramentas tinnitus handicap inventory e escala visual analógica. Toda a amostra recebeu aparelho de amplificação sonora individual e gerador de som, ambos da marca Siemens, participaram de uma sessão de aconselhamento com apoio de material digital e foram avaliados em duas situações: Avaliação inicial (antes da adaptação dos aparelhos de amplificação sonora individual e gerador de som) e Avaliação final (6 meses após a adaptação). As análises estatísticas foram descritivas e inferenciais, adotou-se um nível de significância de 5% com a realização do teste t pareado e o teste de correlação de Spearman. Resultados Os resultados mostraram que houve benefício com o uso de aparelho de amplificação sonora individual combinado ao gerador de som com base nos valores estatisticamente significantes e fortes correlações entre os dados da verificação do gerador de som em relação à acufenometria e os questionários de incômodo/gravidade. Em relação à verificação do gerador de som, é importante destacar que toda a amostra selecionou a estimulação acústica efetiva baseada nos níveis de conforto e no presente estudo demonstraram ser de intensidade suficiente para o prognóstico positivo, enquanto que os ruídos dos usuários estavam abaixo dos limiares psicoacústicos da acufenometria. Conclusão A intervenção audiológica com qualquer nível de estímulo sonoro é suficiente para obter um prognóstico positivo em médio prazo. Os dados que demonstram que a verificação do gerador de som foi efetiva nas medidas da orelha real são importantes na avaliação e intervenção da queixa. Além disso, mostram que quanto maior a percepção do zumbido, maior a sua gravidade; e quanto maior o incômodo, maiores os limiares de frequência psicoacústica e o limiar mínimo de mascaramento.

Relações entre medidas de capacidade auditiva e desempenho em tarefas de percepção da fala em crianças com deficiência auditiva / Relationship between hearing capacity and performance on tasks of speech perception in children with hearing loss

RESUMO Objetivo Estabelecer relações entre o desempenho em tarefa de reconhecimento de palavras com e sem sentido e grau e configuração da perda auditiva, utilizando valores de Índices de Inteligibilidade de Fala (SII) como indicadores, em crianças com deficiência auditiva. Método Foram estabelecidos os SII para sons de entradas de 55 e 65 Decibéis Nível de Pressão Sonora (dBNPS) de dez crianças com perda auditiva neurossensorial usuárias de aparelho de amplificação sonora individual bilateralmente que têm a linguagem oral como principal modalidade de comunicação. As crianças foram submetidas à tarefa de repetição de palavras com e sem sentido em duas ou três diferentes intensidades. As emissões foram analisadas de acordo com o Protocolo Word Association for Syllable Perception (WASP). Na análise dos dados, o SII foi comparado com os resultados obtidos em cada critério de análise. Resultados Para o desempenho em palavras, houve diferença estatisticamente significante entre os dois tipos de estímulo em 55dBNPS. Para o desempenho em consoantes e ponto de articulação, houve diferença estatisticamente significante entre os tipos de estímulos em 65 e 55dBNPS e também entre as intensidades de 65 e 55 dBNPS nas palavras sem sentido. Conclusão De modo geral, não houve regularidade na relação entre capacidade auditiva e desempenho em tarefas de percepção da fala. Os resultados sugerem que o desempenho nas tarefas de reconhecimento de palavras sem sentido tem maior relação com o índice de inteligibilidade do que as palavras com sentido, possivelmente por limitar as estratégias de fechamento semântico pelo sujeito.

ABSTRACT Purpose To establish the relationship between the performance on word recognition tasks, using words with and without sense and degree, and the configuration of hearing loss, by using Speech Inteligibility Index (SII) values as indicators, in children with hearing loss. Methods SII were established for 55 and 65 Decibel of Sound Pressure Level (dB SPL) input sounds of ten children presenting bilateral sensorineural hearing loss (SNHL), adapted with bilateral hearing aids, and who have oral language as the main mode of communication. The children were submitted to a word and nonsense-word repetition task of two or three intensity degrees. Their productions were analyzed according to the Word Association for Syllable Perception (WASP) Protocol. In the data analysis, the values of SII were compared with the results obtained in each analysis criterion. Results Pertaining to the words, there was statistically significant difference between the two types of stimuli in 55 dBSPL. As for the performance of consonants and point of articulation, there was a statistically significant difference between stimuli types in 65 and 55 dB SPL, and between intensities 65 and 55 dB SPL in nonsense words. Conclusion Overall, there was no regularity in the relationship between hearing ability and performance in speech perception tasks. The results suggest that performance in the nonsense words recognition tasks was more related to intelligibility index than to words with meaning, possibly because it limits semantic closure strategies by the subject.

Análise das emissões otoacústicas transitórias por banda de frequência em adolescentes com diabetes mellitus tipo 1 / Transient otoacoustic emissions analysis by frequency bands in adolescents with type 1 diabetes mellitus

Introdução: A associação entre perda auditiva e Diabetes Mellitus tipo 1 (DM1) é ainda pouco estudada. A perda auditiva é uma das complicações crônicas relacionadas ao grau de controle glicêmico, que os pacientes podem apresentar com a progressão da doença. Objetivo: Investigar o comprometimento auditivo por meio das emissões otoacústicas transitórias (EOAT) por banda de frequência em adolescentes com DM1 e relação com o controle glicêmico. Métodos: Foram incluídos 80 adolescentes, 50% do gênero masculino, entre 10 e 19 anos de idade: 40 com DM1 e 40 controles saudáveis, pareados por gênero e idade. Os dados clínicos e laboratoriais foram pesquisados nos prontuários médicos. O controle glicêmico foi avaliado por meio dos exames de hemoglobina glicada e os pacientes com DM1 analisados de acordo com o controle glicêmico. A avaliação auditiva foi realizada por meio da imitanciometria, audiometria, e posteriormente EOAT, em sala tratada acusticamente, pelo protocolo "TE Test" de clique não-linear (1 KHz a 4 kHz) a 80 dB NPS de intensidade (AuDX - Biologic). Resultados: As respostas às EOAT foram ausentes em 5,12% em pacientes com DM1, com diferença significativa em relação aos controles (p=0,04). A análise das EOAT por bandas de frequência mostrou maior proporção de alteração nos adolescentes com DM1 mal controlados quando comparados aos bem controlados, nas frequências de 1000Hz, 2000Hz e 3000Hz (p<0,05). Conclusão: As EOAT por bandas de frequência permitiram a identificação precoce de comprometimento auditivo em adolescentes com DM1 e mostraram associação entre DM1 mal controlado e perda auditiva. (AU)

Introduction: The association between hearing loss and type 1 diabetes mellitus (DM1) is still poorly studied. Hearing loss is one of the chronic complications related to the degree of glycemic control that patients may present with the progression of the disease. Objective: To investigate auditory impairment through transient otoacoustic emissions (TEOAE) by frequency band in adolescents with DM1 and in relation to glycemic control. Methods: Were included 80 adolescents, 50% males, between 10 and 19 years of age: 40 with DM1 and 40 healthy controls, matched by gender and age. Clinical and laboratory data were taken from the medical records. Glycemic control was evalueted by glycated hemoglobin and the patients with DM1 were analyzed according to glycemic control. To the auditory evaluation were used the immittance and audiometry, and the TEOAE. The test was performed in the acoustically treated room, the non-linear TE test protocol (1 KHz to 4 kHz) at 80 dB SPL (AuDX - Biologic ). Results: TEOAE responses were absent in 5.12% of patients with DM1, with a significant difference in relation to controls (p = 0.04). The analysis of TEOAE by frequency bands showed a higher proportion of alteration in adolescents with DM1 poorly controlled when compared to well controlled ones, in the frequencies of 1000Hz, 2000Hz and 3000Hz (p <0.05). Conclusion: TEOAE by frequency bands allowed the early identification of auditory impairment in adolescents with DM1 and showed an association between poorly controlled DM1 and hearing loss. (AU)

Gender differences in binaural speech-evoked auditory brainstem response: are they clinically significant? / Diferenças de gênero no potencial evocado auditivo de tronco encefálico com estímulo de fala binaural: são clinicamente significantes?

Abstract Introduction: Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported. Objective: The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations. Methods: A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age = 23.6 ± 2.3 years) and the remaining sixteen were males (mean age = 22.0 ± 2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally. Results: While latencies were not affected (p > 0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p < 0.05). As revealed by large effect sizes (d > 0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes. Conclusion: The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults.

Resumo Introdução: Potenciais auditivos evocados de modo binaural apresentam bons valores diagnósticos ao testar indivíduos com déficits auditivos centrais. A literatura sobre a resposta do potencial evocado do tronco encefálico com estímulo de fala de modo binaural é, de fato, limitada. As diferenças de gênero nos resultados desse exame têm sido consistentemente observadas, mas a magnitude da diferença de gênero ainda não foi relatada. Objetivo: Comparar a magnitude da diferença de gênero nos resultados do potencial evocado do tronco encefálico com estímulo de fala entre estímulos monaural e binaural. Método: Um total de 34 adultos asiáticos saudáveis com idades entre 19 e 30 anos participaram deste estudo comparativo. Dezoito deles eram do sexo feminino (média de idade = 23,6 ± 2,3 anos) e os outros dezesseis do sexo masculino (média de idade = 22,0 ± 2,3 anos). Para cada indivíduo, o potencial evocado do tronco encefálico com estímulo de fala foi registrado com a sílaba sintetizada /da/ apresentada de forma monaural e binaural. Resultados: Embora as latências não tenham sido afetadas (p > 0,05), a estimulação binaural produziu amplitudes de potencial evocado do tronco encefálico com estímulo de fala estatisticamente maiores do que a estimulação monaural (p < 0,05). Como demonstrado pelos grandes tamanhos de efeito (d > 0,80), diferenças substanciais de gênero foram observadas na maioria dos picos de potencial evocado do tronco encefálico com estímulo de fala para ambos os modos de estímulo. Conclusão: A magnitude da diferença de gênero entre os dois modos de estímulo revelou alguns padrões distintos. Com base nesses resultados clinicamente significantes, os dados normativos específicos para o gênero são altamente recomendados quando se usa o potencial evocado do tronco encefálico com estímulo de fala para aplicações clínicas e futuras. Os dados normativos preliminares fornecidos pelo presente estudo podem servir como referência para futuros estudos sobre esse exame em asiáticos adultos.

Analysis of the Effect of Musical Stimulation on Cortical Auditory Evoked Potentials

Abstract Introduction Cortical auditory evoked potentials (CAEPs) are bioelectric responses that occur from acoustic stimulations, and they assess the functionality of the central auditory system. Objective The objective of the present study was to analyze the effect of musical stimulation on CAEPs. Methods The sample consisted of 42 healthy female subjects, aged between 18 and 24 years, divided into two groups - G1: without musical stimulation prior to the CAEP examination; and G2: with stimulation prior to the examination. In both groups, as a pre-collection procedure, the complete basic audiological evaluation was performed. For the musical stimulation performed in G2, we used an MP4 player programmed to play Pachelbel's "Canon in D Major" for five minutes prior to the CAEP examination. To analyze the effect on the groups, the ear side and the ide-group interaction , a mixed analysis of variance (ANOVA) of repeated measures was performed. Box M test and Mauchly sphericity test were also performed. Results Test differences were considered statistically significant when the p-value was < 0.05 (5%). Thus, it was possible to observe that there was a statistically significant difference of the P2 component characterized by the decrease in the amplitude of response in the left ear in G2 when comparing the responses of CAEP with and without prior musical stimulation. Conclusion The result of the present study enabled us to conclude that there was a change in the response of CAEPs with musical stimulation. (AU)

Mensuração do esforço auditivo com o uso de um paradigma de tarefa dupla do Português Brasileiro: estudo-piloto / Measurement of listening effort using of a dual-task paradigm of Brazilian Portuguese: a pilot study

RESUMO Objetivo Mensurar o esforço auditivo com o uso de um paradigma de tarefa dupla de memória operacional e analisar a significância clínica do desempenho de indivíduos normo-ouvintes. Método Participaram 10 adultos jovens, entre 18 e 30 anos, de ambos os gêneros, normo-ouvintes classificados segundo a média quadritonal (500, 1000, 2000 e 4000Hz) e com nível sociocultural similar. Os participantes foram submetidos à anamnese audiológica, meatoscopia e audiometria tonal limiar. Para a mensuração do esforço auditivo, utilizou-se um paradigma de tarefa dupla, composto por tarefas de percepção de fala e memória operacional de logatomas, palavras reais e sentenças sem sentido. Anteriormente à mensuração, o paradigma de tarefa dupla foi realizado no silêncio com o intuito de treinar os participantes a desempenharem as tarefas adequadamente. Após a fase de treinamento, este paradigma foi realizado em duas situações de escuta distintas, nas relações sinal/ruído de +5 e -5dB, com o ruído do tipo White Noise. Resultados A comparação do desempenho por orelha, direita ou esquerda, nas duas relações sinal-ruído demonstrou efeito significante para as tarefas de percepção de fala de logatomas e sentenças sem sentido em ambas as orelhas, porém para a tarefa de esforço auditivo e memória operacional houve diferença significante apenas para a orelha direita. Conclusão Foi possível mensurar o esforço auditivo com o uso do paradigma proposto e este instrumento demonstrou ser sensível para a quantificação deste parâmetro auditivo.

ABSTRACT Purpose To measure listening effort using of a dual-task paradigm of working memory and analyze the clinical significance of the normal-hearing individuals' performance. Methods Participants were 10 young adults with similar socio-cultural level, aged 18-30 years, of both genders, classified as normal-hearing individuals based on the quadritonal average (500, 1000, 2000 and 4000 Hz). The participants were submitted to audiological anamnesis, meatoscopy, and pure tone audiometry. Listening effort was measured using a dual-task paradigm comprising the tasks of speech perception and working memory with logatomes, real words, and meaningless sentences. Prior to measurement, the dual-task paradigm was carried out in audiometric booth in order to train the participants to perform the tasks properly. After the training stage, this paradigm was conducted under two different hearing situations with white noise: signal-to-noise ratios of +5 and -5dB. Results Performance comparison per ear, right or left, for the two signal-to-noise ratios significantly influenced the speech perception tasks with logatomes and meaningless sentences in both ears; however, significant difference was observed only for the right ear in the tasks of listening effort and working memory. Conclusion Listening effort can be measured using the paradigm proposed, and this instrument was proven sensitive for the quantification of this auditory parameter.

Outcomes of Automated Auditory Evoked Potential Performed in Different Settings and the Factors Associated with Referred Cases

Abstract Introduction For the population with risk factors for hearing loss, the first option to assess the hearing status is the performance of the automated brainstem auditory evoked potential (BAEP) test because of its efficacy in identifying retrocochlear hearing loss. Objective To verify the outcomes of automated BAEP performed in different settings as well as the factors associated with the prevalence of hearing impairment. Methods Cross-sectional study conducted from October of 2014 to May of 2015. The sample consisted of 161 infants with at least one risk factor for hearing loss who underwent automated BAEP during the hospital stay or at the outpatient clinic. After 30 days, the altered cases were referred for BAEP diagnosis. Results One hundred and thirty-eight infants (86%) had a result of "pass" and 23 (14%) of "failure" in the automated BAEP. There was no statistically significant difference in the rate of "referred" results between examinations performed in different settings. The infants' ages did not influence the number of abnormal cases. All of the 23 infants who presented a "referred" result in the automated BAEP, unilateral or bilateral, were sent for BAEP diagnosis, and out of these, 9 (39%) remained with at least some degree of alteration. The average age of diagnosis was 2.7 months. Conclusion The results of the automated BAEP were similar when performed during hospitalization or after discharge. Neither the age at the examination nor the gender of the patient influenced the prevalence of hearing loss.

Effect of Fractal Tones on the Improvement of Tinnitus Handicap Inventory Functional Scores among Chronic Tinnitus Patients: An Open-label Pilot Study

Abstract Introduction Music-based sound therapies become recently a trend in the treatment of tinnitus. Few publications have studied the therapeutic use of fractal tones to treat chronic tinnitus. Objective The aim of this study was to determine the benefits of using fractal tones as a unique sound therapy for chronic tinnitus sufferers. Methods Twelve participants were recruited; however, six could not be assigned. At baseline and at 1, 3 and 6 months, the participants were provided with the Tinnitus Handicap Inventory (THI) and Hearing Handicap Inventory for Adults (HHIA) questionnaires, and their visual analog scale score was recorded. Tinnitus pitch and loudness matching was performed before fitting and after 6 months of use. Results The visual analog scale (VAS) score, pitch and loudness matching and minimal masking levels did not result in significant improvement at the end of the treatment. The mean THI measured at baseline was 45, and the final one was 25. A paired sample t-test showed that this 20-point difference was statistically significant. Conclusions We measured the benefits of using fractal tone therapy for the treatment of chronic tinnitus and found that most of the benefits were in the THI functional domain, which includes concentration, reading, attention, consciousness, sleep, social activities, and household tasks. For all patients with bothersome chronic tinnitus and high scores on the THI functional scale, fractal tones should be considered a promising initial sound therapy strategy. The findings from this open-label pilot study are preliminary, and further trials are needed before these results can be generalized to a larger tinnitus population.

Parameters for Applying the Brainstem Auditory Evoked Potential with Speech Stimulus: Systematic Review

Abstract Introduction Studies using the Brainstem Auditory Evoked Potential with speech stimulus are increasing in Brazil, and there are divergences between the methodologies used for testing. Objectives To analyze the parameters used in the study of the Brainstem Auditory Evoked Potentials with speech stimulus. Data Synthesis The survey was performed using electronic databases. The search strategy was as follows: "Evoked potentials, auditory" OR "Brain stem" OR "Evoked potentials, auditory, brain stem" AND "Speech." The survey was performed from June to July of 2016. The criteria used for including articles in this study were: being written in Portuguese, English or Spanish; presenting the description of the testing parameters and the description of the sample. In the databases selected, 2,384 articles were found, and 43 articles met all of the inclusion criteria. The predominance of the following parameters was observed to achieve the potential during study: stimulation with the syllable /da/; monaural presentation with greater use of the right ear; intensity of 80 dB SPL; vertical placement of electrodes; use of in-ear headphones; patient seated, distracted in awake state; alternating polarity; use of speech synthesizer software for the elaboration of stimuli; presentation rate of 10.9/s; and sampling rate of 20 kHz. Conclusions The theme addressed in this systematic review is relatively recent. However, the results are significant enough to encourage the use of the procedure in clinical practice and advise clinicians about the most used procedures in each parameter.

Hearing in Noise Test, HINT-Brazil, in normal-hearing children / Teste de Reconhecimento de Fala no Ruído, HINT-Brasil, em crianças normo-ouvintes

Abstract Introduction: The auditory processing is related to certain skills such as speech recognition in noise. The HINT-Brazil test allows the measurement of the Speech/Noise ratio however there are no studies in the national literature that establish parameters for the child population. Objective: To analyze the performance of normal-hearing subjects aged 8-10 years old in tasks for speech recognition in noise using HINT test. Methods: Sixty schoolchildren were evaluated. They were between 8 and 10 years of age, of both genders, and had no auditory and school complaints, with results ranking within normality for the Basic Audiological Assessment and the Dichotic Digits Test. HINT-Brazil test was applied with headphones, with the Speech/Noise ratio in conditions of frontal noise, noise to the right, and noise to the left being investigated. The software calculated the Composite Noise, which corresponds to the weighted mean of the tested conditions. Results: There was no statistically significant difference between the ears, nor between the genders. There was a statistically significant difference for age ranges of 8 and 10 years, in situations with noise, and for Composite Noise. The age group of 10 years showed better performance than the age group of 8; the age group of 9 years did not show statistically significant difference regarding the other age ranges. We suggest the values of mean and standard deviation of the Speech/Noise ratio, considering the age ranges of: 8 years - Frontal Noise: −2.09 (±1.09); Right Noise: −7.64 (±1.72); Left Noise: −7.53 (±2.80); Composite Noise: −4.86 (±1.31); 9 years - Frontal Noise: −2.82 (±0.74); Right Noise: −8.49 (±2.24); Left Noise: −8.41 (±1.75); Composite Noise: −5.63 (±1.02); 10 years - Frontal Noise: −3.01 (±0.95); Right Noise: −9.47 (±1.43); Left Noise: −9.16 (±1.65); Composite Noise: −6.16 (±0.91). Conclusion: HINT-Brazil test is a simple and fast test, and is not difficult to performed with normal-hearing children. The results confirm that it is an efficient test to be used with the age range evaluated.

Resumo Introdução: O processamento auditivo está relacionado a determinadas habilidades, como o reconhecimento de fala no ruído. O teste HINT-Brasil permite a mensuração da relação Fala/Ruído, porém, não há na literatura nacional estudos que estabeleçam parâmetros para a população infantil. Objetivo: Analisar o desempenho de normo-ouvintes, de 8 a 10 anos, nas tarefas de reconhecimento de fala no ruído, por meio do teste HINT. Método: Avaliados 60 escolares, entre 8 e 10 anos, de ambos os gêneros, sem queixas auditivas e escolares, e com resultados dentro da normalidade para a Avaliação Audiológica Básica e o Teste Dicótico de Dígitos. O teste HINT-Brasil foi aplicado com fones de ouvido, sendo pesquisada a relação Fala/Ruído nas condições Ruído Frontal, Ruído à Direita e Ruído à Esquerda. O software calculou o Ruído Composto, que corresponde à média ponderada das condições testadas. Resultados: Não houve diferença estatisticamente significante entre as orelhas, nem entre os gêneros. Houve diferença estatisticamente significante para as faixas de 8 e 10 anos, nas situações com ruído e para o Ruído Composto. A faixa etária de 10 anos apresentou desempenho melhor do que a faixa etária de 8; a faixa etária de 9 anos não apresentou diferença estatisticamente significante com relação as outras faixas etárias. Sugerimos os valores de Média e Desvio Padrão da relação F/R, considerando as faixas: 8 anos - RF: -2,09 (± 1,09); RD: -7,64 (± 1,72); RE: -7,53 (± 2,80); RC: -4,86 (± 1,31); 9 anos - RF: -2,82 (± 0,74); RD: -8,49 (± 2,24); RE: -8,41 (± 1,75); RC: -5,63 (± 1,02); 10 anos - RF: -3,01 (± 0,95); RD: -9,47 (± 1,43); RE: -9,16 (± 1,65); RC: -6,16 (± 0,91). Conclusão: O teste HINT-Brasil é um teste simples e rápido e não oferece dificuldades em seu uso com crianças normo-ouvintes; os resultados mostram se tratar de um teste eficaz para ser utilizado com a faixa etária avaliada.

Eficácia do treinamento auditivo utilizando o software Programa de Escuta no Ruído (PER) em escolares com transtorno do processamento auditivo e baixo desempenho escolar / Efficacy of auditory training using the Programa de Escuta no Ruído (PER) software in students with auditory processing disorders and poor school performance

RESUMO Objetivo investigar a eficácia do treinamento auditivo nessa população, utilizando o software Programa de Escuta no Ruído (PER), que aborda, entre as habilidades de processamento auditivo, a escuta no ruído. Método participaram deste estudo 18 crianças com idades entre 8 e 10 anos, de ambos os gêneros. Todos os sujeitos participaram das seguintes etapas: avaliação pré-intervenção, intervenção constituída por treino placebo, reavaliação do processamento auditivo e treino auditivo e reavaliação pós-intervenção, de forma que o sujeito seja controle dele mesmo. Resultados não houve diferença estatisticamente significante entre a avaliação pré-intervenção e a reavaliação do processamento auditivo pós-treino placebo, mas houve diferença estatisticamente significante entre as condições pré e pós-treinamento auditivo. Conclusão o presente estudo alcançou seu objetivo geral. O software PER se mostrou eficaz para o treinamento auditivo em escolares com transtorno do processamento auditivo e baixo desempenho escolar.

ABSTRACT Purpose Investigate the efficacy of auditory training in students with auditory processing disorders and poor school performance using the software Programa de Escuta no Ruído (PER), which addresses auditory processing skills, specifically listening in noise. Methods Eighteen children aged 8-10 years, of both genders, participated in this study. All individuals participated in the following stages: pre-intervention assessment, intervention (consisting of placebo training, re-evaluation of auditory processing, and auditory training), and post-intervention assessment, so that the same individual is self-control. Results No statistically significant difference was observed between the pre-intervention assessment and the post-training auditory processing re-evaluation of the placebo, but statistically significant difference was found between the pre- and post-auditory training conditions. Conclusion The present study achieved its general objective. The PER software proved to be effective for the auditory training of students with auditory processing disorders and poor school performance.

Effect of auditory-motor training on auditory processing of school children / Efeito do treinamento auditivo-motor no processamento auditivo de escolares

ABSTRACT Objective To compare performance in Avaliação Simplificada do Processamento Auditivo Central and Scale of Auditory Behaviors scores before and after auditory and motor training. Methods Sample comprising 162 children aged 9 to 11 years and attending public schools in the city of São Paulo (SP), Brazil; 122 out of 162 children were allocated to one of three experimental groups: Multisensory; Auditory/Motor and Motor/Auditory. Experimental groups were submitted to 8 hours of auditory, visuospatial and motor stimulation over the course of 8 weeks. The remaining 40 children formed the Control Group and received no stimulation. Results Relation between child behavior as perceived by school teachers and auditory test responses revealed that the better the performance in auditory processing assessment, the higher the Scale of Auditory Behaviors scores. Conclusion Auditory and motor training led to improvements in auditory processing skills as rated by Avaliação Simplificada do Processamento Auditivo Central and Scale of Auditory Behaviors; this intervention model proved to be a good tool for use in school settings.

RESUMO Objetivo Comparar as respostas da Avaliação Simplificada do Processamento Auditivo Central às da Scale of Auditory Behaviors antes e depois de um treinamento auditivo e de habilidades motoras. Métodos Participaram 162 escolares de 9 a 11 anos de escola pública municipal da cidade de São Paulo (SP), sendo 122 deles divididos em três grupos experimentais: Multissensorial; Auditivo/Motor e Motor/Auditivo. Eles receberam estimulação auditiva, visuoespacial e motora durante 8 semanas (8 horas). O Grupo Controle, que não recebeu estimulação, foi formado por 40 escolares. Resultados A relação entre a percepção dos professores sobre o comportamento dos alunos e suas respostas em testes auditivos mostrou que quanto melhor o resultado na avaliação do processamento auditivo, melhores os escores da Scale of Auditory Behaviors. Conclusão Após treinamento auditivo e motor, ocorreu melhora significativa das habilidades do processamento auditivo demonstradas pela Avaliação Simplificada do Processamento Auditivo Central e na Scale of Auditory Behaviors, e este modelo de intervenção consistiu em boa ferramenta para uso na escola.

LS CE-Chirp® vs. Click in the neuroaudiological diagnosis by ABR / LS CE-Chirp® vs. Clique no diagnóstico neuroaudiológico pelo PEATE

Abstract Introduction: The chirp stimulus was developed seeking to counterbalance the delay of the sound wave on its journey through the cochlea, allowing the hair cells to depolarize at the same time. The result is a simultaneous stimulation providing better neural synchrony and, consequently, the recording of responses with greater amplitudes. Objective: To compare the absolute latency of waves I, III and V, the interpeak intervals I-III, III-V and I-V, amplitude values of wave V and its association with the amplitude of wave I, and the interaural difference V-V in the auditory brainstem response (ABR) using Click and LS CE-Chirp® stimuli to determine whether the responses evoked by LS CE-Chirp® could be applied to neuroaudiological diagnosis. Methods: Cross-sectional study with 30 normal-hearing individuals. The parameters used were: intensity of 85 dBnHL, alternating polarity; 17.1 stimuli/s and 100-3000 Hz filters. Results: The absolute latencies of waves I, III and V observed with LS CE-Chirp® and click did not show significant differences. Significantly higher amplitudes of wave V were observed with the LS CE-Chirp®. The interaural difference between the wave V latencies between stimuli showed no significant difference. Conclusion: The LS CE-Chirp® stimulus was shown to be as efficient as the click to capture ABR at high levels of stimulation, with the advantage of producing greater-amplitude V waves.

Resumo Introdução: O chirp foi desenvolvido para compensar o atraso da onda sonora em seu trajeto pela cóclea e possibilitar que as células ciliadas despolarizassem ao mesmo tempo. O resultado é uma estimulação simultânea que proporciona uma melhor sincronia neural e consequentemente o registro de respostas ocorre com maiores amplitudes. Objetivo: Comparar a latência absoluta das ondas I, III e V, os intervalos interpicos I-III, III-V e I-V, os valores de amplitude da onda V e sua relação com a amplitude da onda I e a diferença interaural V-V no Potencial Evocado Auditivo de Tronco Encefálico com o uso dos estímulos clique e LS CE-Chirp®, a fim de determinar se as respostas evocadas por LS CE-Chirp® poderiam ter aplicabilidade no diagnóstico neuroaudiológico. Método: Estudo transversal com 30 indivíduos normo-ouvintes. Os parâmetros usados foram: intensidade de 85 dBnNA, polaridade alternada; 17,1 estímulo/s e filtros de 100-3000 Hz. Resultado: As latências absolutas das ondas I, III e V observadas com LS CE-Chirp® e clique não tiveram diferenças significativas. Amplitudes significativamente maiores da onda V foram observadas com o LS CE-Chirp®. A diferença interaural entre as latências da onda V entre os estímulos não mostrou variação significativa. Conclusão: O estímulo LS CE-Chirp® mostrou ser tão eficiente quanto o clique na captação do potencial evocado auditivo de tronco encefálico, em níveis elevados de estimulação, com a vantagem de produzir ondas V de maior amplitude.

Temporal processing and long-latency auditory evoked potential in stutterers / Processamento temporal e potencial evocado auditivo de longa latência em indivíduos gagos

Abstract Introduction: Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. Objective: To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. Methods: The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n = 20) and non-stutters (n = 21), compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Results: Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Conclusion: Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components.

Resumo Introdução: A gagueira é um distúrbio da fluência da fala e pode estar associada a fatores neuroaudiológicos ligados ao processamento auditivo central, entre eles as alterações das habilidades auditivas de processamento e resolução temporal. Objetivo: Caracterizar o processamento temporal e o potencial evocado auditivo de longa latência em indivíduos gagos e compará-los com indivíduos sem gagueira. Método: Participaram do estudo 41 indivíduos destros, de 18 a 46 anos, distribuídos em dois grupos: 20 com gagueira e 21 sem gagueira, comparados segundo idade, escolaridade e gênero. Todos os indivíduos foram submetidos aos testes de padrão de duração, teste de identificação de intervalos aleatórios e o potencial evocado auditivo de longa latência. Resultados: Indivíduos com gagueira apresentaram pior desempenho nos testes de padrão de duração e Random Gap Detection, quando comparados com os indivíduos fluentes. No potencial evocado auditivo de longa latência, houve diferença na latência dos componentes N2 e P3, os indivíduos gagos apresentaram maiores valores de latência. Conclusão: Os indivíduos com gagueira apresentaram processamento temporal com desempenho abaixo do esperado e um maior valor de latência para os componentes N2 e P3.

Mode of recording and modulation frequency effects of auditory steady state response thresholds / Modo de registro e efeitos da modulação em frequências nos limiares de resposta auditiva de estado estável

Abstract Introduction The performance of auditory steady state response (ASSR) in threshold testing when recorded ipsilaterally and contralaterally, as well as at low and high modulation frequencies (MFs), has not been systematically studied. Objective To verify the influences of mode of recording (ipsilateral vs. contralateral) and modulation frequency (40 Hz vs. 90 Hz) on ASSR thresholds. Methods Fifteen female and 14 male subjects (aged 18–30 years) with normal hearing bilaterally were studied. Narrow-band CE-chirp® stimuli (centerd at 500, 1000, 2000, and 4000 Hz) modulated at 40 and 90 Hz MFs were presented to the participants' right ear. The ASSR thresholds were then recorded at each test frequency in both ipsilateral and contralateral channels. Results Due to pronounced interaction effects between mode of recording and MF (p < 0.05 by two-way repeated measures ANOVA), mean ASSR thresholds were then compared among four conditions (ipsi-40 Hz, ipsi-90 Hz, contra-40 Hz, and contra-90 Hz) using one-way repeated measures ANOVA. At the 500 and 1000 Hz test frequencies, contra-40 Hz condition produced the lowest mean ASSR thresholds. In contrast, at high frequencies (2000 and 4000 Hz), ipsi-90 Hz condition revealed the lowest mean ASSR thresholds. At most test frequencies, contra-90 Hz produced the highest mean ASSR thresholds. Conclusions Based on the findings, the present study recommends two different protocols for an optimum threshold testing with ASSR, at least when testing young adults. This includes the use of contra-40 Hz recording mode due to its promising performance in hearing threshold estimation.

Resumo Introdução O desempenho da resposta auditiva de estado estável (RAEE) em testes de limiar com registros ipsilateral e contralateral e modulações em frequências (MFs) não tem sido sistematicamente estudado. Objetivo Verificar a influência do modo de registro (ipsilateral vs. contralateral) e da modulação em frequências (40 Hz vs. 90 Hz) nos limiares de RAEE. Método Foram estudados 15 mulheres e 14 homens (18-30 anos) com audição bilateral normal. Estímulos CE-chirp® de banda estreita (centrados em 500, 1.000, 2.000 e 4.000 Hz) modulados em 40 e 90 Hz de MF foram apresentados à orelha direita dos participantes. Em seguida, os limiares de RAEE foram registrados em cada frequência de teste nos canais ipsilateral e contralateral. Resultados Devido aos pronunciados efeitos de interação entre o modo de registro e MF (p < 0,05 por variância com dois fatores para medidas repetidas – Anova duas vias), os limiares médios de RAEE foram então comparados entre quatro condições (Ipsi-40 Hz, Ipsi-90 Hz, Contra-40 Hz e Contra-90 Hz), com o uso de variância e com um fator para medidas repetidas (Anova uma via). Nas frequências de teste de 500 e 1.000 Hz, a condição Contra-40 Hz produziu os mais baixos limiares médios de RAEE. Em contraste, em altas frequências (2.000 e 4.000 Hz), a condição Ipsi-90 Hz revelou os mais baixos limiares médios de RAEE. Na maioria das frequências de teste, a condição Contra-90 Hz produziu os mais elevados limiares médios de RAEE. Conclusões Com base nos achados do presente estudo, os autores recomendam dois protocolos diferentes para um teste de limiares ideal com RAEE, pelo menos em adultos jovens. Isso inclui o uso do modo de registro Contra-40 Hz, devido ao seu desempenho promissor nas estimativas do limiar auditivo.