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Audiol., Commun. res ; 27: e2643, 2022. tab, graf
Article in Portuguese | LILACS | ID: biblio-1393981


RESUMO Objetivos Buscar na literatura informações quanto aos aspectos que guiam o monitoramento audiológico infantil, descrevendo os procedimentos utilizados, a idade em que são realizados, qual a população monitorada e os países que mais estudam sobre o assunto. Além de discutir a importância dessa etapa e a eficácia desses aspectos. Estratégia de pesquisa A revisão foi conduzida com base nas recomendações PRISMA e registrada na plataforma PROSPERO. Os estudos foram pesquisados nas bases de dados eletrônicas Medline (Pubmed), Web of Science e SciELO, com os descritores hearing, neonatal screening e follow up. Critérios de seleção Foram incluídos estudos que descrevessem o monitoramento audiológico. Não foram empregados filtros do ano de publicação, tampouco para os idiomas dos mesmos. Resultados Foram encontrados 432 artigos e 21 foram incluídos nesse estudo, sendo que a maioria foi produzida em países desenvolvidos. O Potencial Evocado Auditivo de Tronco Encefálico e a Avaliação Comportamental foram os procedimentos mais utilizados. Quanto a idade e população, a maioria realiza o monitoramento até os três anos e em crianças com Indicadores para a Deficiência Auditiva. Conclusão Os estudos demonstraram que não há padrão entre os protocolos para a realização do monitoramento audiológico, porém foi possível identificar que as pesquisas apresentam uma maior concordância quanto a idade em que tal monitoramento acontece e qual a população que deve ser monitorada. Entretanto, embora haja discordâncias, os métodos de avaliação utilizados pelos estudos são eficazes para a detecção de perdas auditiva de caráter leve, progressivo e/ou tardio, além dos casos de falso negativo.

ABSTRACT Purpose To search the literature for guidelines on infant's audiological monitoring, most commonly used procedures, the age at which they are performed, which population should be monitored and the countries that study the subject the most. Besides, the importance and effectiveness of these measures will be discussed. Research strategy The review was conducted based on the PRISMA recommendations, registered on the PROSPERO platform. The studies were searched for in the electronic databases Medline (Pubmed), Web of Science and SciELO, using the descriptors hearing, neonatal screening and follow up. Selection criteria studies reporting the audiological monitoring were included. No filters on year and language of publication were used. Results A total of 432 articles were found and 21 were included in this study, mostly produced in developed countries. The Auditory Brainstem Response and the Behavioral Assessment were the most frequently used procedures. As to age and population, most infants are subjected to audiological monitoring up to three years of age and have Risk Factors for Hearing Loss in their clinical history. Conclusion The studies pointed that there is no standard among the protocols for performing audiological monitoring, but it was possible to identify agreement as to the age at which such monitoring takes place and which population should be monitored. However, although there is some disagreement, the assessment methods used in the studies are effective in detecting mild, progressive and/or late hearing loss, in addition to false negative cases.

Humans , Infant, Newborn , Infant , Evoked Potentials, Auditory, Brain Stem , Audiology , Neonatal Screening , Hearing Loss/prevention & control , Otoacoustic Emissions, Spontaneous , Risk Index
Acta Physiologica Sinica ; (6): 489-494, 2022.
Article in Chinese | WPRIM | ID: wpr-939583


High level noise can damage cochlear hair cells, auditory nerve and synaptic connections between cochlear hair cells and auditory nerve, resulting in noise-induced hearing loss (NIHL). Recent studies have shown that animal cochleae have circadian rhythm, which makes them different in sensitivity to noise throughout the day. Cochlear circadian rhythm has a certain relationship with brain-derived neurotrophic factor and glucocorticoids, which affects the degree of hearing loss after exposure to noise. In this review, we summarize the research progress of the regulation of cochlear sensitivity to noise by circadian rhythm and prospect the future research direction.

Animals , Auditory Threshold , Circadian Rhythm , Cochlea , Evoked Potentials, Auditory, Brain Stem/physiology , Hair Cells, Auditory , Hearing Loss, Noise-Induced , Noise/adverse effects
Article in Chinese | WPRIM | ID: wpr-935786


Objective: To study the protective effects of metformin on noise-induced hearing loss (NIHL) and its differential protein omics expression profile. Methods: In January 2021, 39 male Wistar rats were randomly divided into control group, noise exposure group and metformin+noise exposure group, with 13 rats in each group. Rats in the noise exposure group and metformin+noise exposure group were continuously exposed to octave noise with sound pressure level of 120 dB (A) and center frequency of 8 kHz for 4 h. Rats in the metformin+noise exposure group were treated with 200 mg/kg/d metformin 3 d before noise exposure for a total of 7 d. Auditory brainstem response (ABR) was used to test the changes of hearing thresholds before noise exposure and 1, 4, 7 d after noise exposure in the right ear of rats in each group. Tandem mass tag (TMT) quantitative proteomics was used to identify and analyze the differentially expressed protein in the inner ear of rats in each group, and it was verified by immunofluorescence staining with frozen sections. Results: The click-ABR thresholds of right ear in the noise exposure group and metformin+noise exposure group were significantly higher than those in the control group 1, 4, 7 d after noise exposure (P<0.05) . The click-ABR threshold of right ear in the metformin+noise exposure group were significantly lower than that in the noise exposure group (P<0.05) . Compared with the noise exposure group, 1035 up-regulated proteins and 1145 down-regulated proteins were differentially expressed in the metformin+noise exposure group. GO enrichment analysis showed that the significantly differentially expressed proteins were mainly involved in binding, molecular function regulation, signal transduction, and other functions. Enrichment analysis of KEGG pathway revealed that the pathways for significant enrichment of differentially expressed proteins included phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway, focal adhesion, diabetic cardiomyopathy, mitogen, and mitogen-activated protein kinase (MAPK) signaling pathway. Immunofluorescence experiments showed that compared with the noise exposure group, the fluorescence intensity of insulin-like growth factor 1 receptor (IGF1R) in the metformin+noise exposure group was increased, and the fluorescence intensity of eukaryotic translation initiation factor 4E binding protein 1 (eIF4EBP1) was decreased. Conclusion: Noise exposure can lead to an increase in rat hearing threshold, and metformin can improve noise-induced hearing threshold abnormalities through multiple pathways and biological processes.

Animals , Auditory Threshold/physiology , Cochlea , Ear, Inner , Evoked Potentials, Auditory, Brain Stem/physiology , Hearing Loss, Noise-Induced/prevention & control , Male , Metformin/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Rats , Rats, Wistar
Chinese Journal of Traumatology ; (6): 156-160, 2022.
Article in English | WPRIM | ID: wpr-928492


PURPOSE@#Auditory nerve injury is one of the most common nerve injury complications of skull base fractures. However, there is currently a lack of auxiliary examination methods for its direct diagnosis. The purpose of this study was to find a more efficient and accurate means of diagnosis for auditory nerve injury.@*METHODS@#Through retrospectively analyzing the results of brainstem auditory evoked potential (BAEP) and high-resolution CT (HRCT) in 37 patients with hearing impairment following trauma from January 1, 2018 to July 31, 2020, the role of the two inspection methods in the diagnosis of auditory nerve injury was studied. Inclusion criteria were patient had a clear history of trauma and unilateral hearing impairment after trauma; while exclusion criteria were: (1) severe patient with a Glasgow coma scale score ≤5 because these patients were classified as severe head injury and admitted to the intensive care unit, (2) patient in the subacute stage admitted 72 h after trauma, and (3) patient with prior hearing impairment before trauma. According to Goodman's classification of hearing impairment, the patients were divided into low/medium/severe injury groups. In addition, patients were divided into HRCT-positive and negative groups for further investigation with their BAEP results. The positive rates of BEAP for each group were observed, and the results were analyzed by Chi-square test (p < 0.05, regarded as statistical difference).@*RESULTS@#A total of 37 patients were included, including 21 males and 16 females. All of them were hospitalized patients with GCS score of 6-15 at the time of admission. The BAEP positive rate in the medium and severe injury group was 100%, which was significantly higher than that in the low injury group (27.27%) (p < 0.01). The rate of BEAP positivity was significantly higher in the HRCT-positive group (20/30, 66.7%) than in the HRCT-negative group (1/7, 14.3%) (p < 0.05). Twenty patients (54.05%) were both positive for BEAP and HRCT test, and considered to have auditory nerve damage. Six patients (16.22%) were both negative for BEAP and HRCT test, and 10 patients (27.03%) were BAEP-negative but HRCT-positive: all the 16 patients were considered as non-neurological injury. The rest 1 case (2.70%) was BAEP-positive but HRCT-negative, which we speculate may have auditory nerve concussion.@*CONCLUSION@#By way of BAEP combining with skull base HRCT, we may improve the accuracy of the diagnosis of auditory nerve injury. Such a diagnostic strategy may be beneficial to guiding treatment plans and evaluating prognosis.

Cochlear Nerve , Evoked Potentials, Auditory, Brain Stem/physiology , Female , Hearing Loss , Humans , Male , Retrospective Studies , Skull Base/diagnostic imaging , Tomography, X-Ray Computed
Distúrb. comun ; 33(2): 339-348, jun. 2021. tab, ilus
Article in Portuguese | LILACS | ID: biblio-1401537


Introdução: A triagem auditiva neonatal universal (TANU) é realizada por meio do exame de potencial evocado auditivo de tronco encefálico (PEATE), na população com indicador de risco para deficiência auditiva. A resposta auditiva de estado estável (RAEE) é uma técnica objetiva e automática de determinação dos limiares auditivos por frequência específica, porém ainda pouco explorada antes da alta hospitalar. Objetivo: analisar os resultados obtidos no exame de PEATE e RAEE em lactentes com indicadores de risco para deficiência auditiva, antes da alta hospitalar, com e sem falha na TANU. Métodos: Estudo observacional analítico prospectivo feito em lactentes com risco para a deficiência auditiva e que realizaram o PEATE e a RAEE na mesma sessão. Resultados: Atenderam ao critério de inclusão 66 lactentes, de ambos os gêneros, idade mediana de 1,2 meses, idade gestacional média de 31 semanas, peso médio ao nascimento 1601 g. Tiveram PEATE normal, 53 (80%) lactentes, denominados de G1 e 13 (20%) tiveram PEATE alterado, denominados de G2. Os limiares eletrofisiológicos da RAEE foram estatisticamente menores nos lactentes de G1. Conclusão: Houve relação entre os achados dos exames de PEATE e RAEE em lactentes de risco para deficiência auditiva, quando realizado antes da alta hospitalar. A mediana dos limiares eletrofisiológicos da RAEE foi menor para os lactentes que tiveram PEATE normal e maior para aqueles que tiveram PEATE alterado na TANU.

Introduction: Universal neonatal hearing screening (UNHS) is performed by examining brainstem auditory evoked potential (BAEP), in the population with a risk indicator for hearing loss. The auditory steady-state response (ASSR) is an objective and automatic technique for determining hearing thresholds by specific frequency, but still little explored before hospital discharge. Objective: to analyze the results obtained in the BAEP and RAEE tests in infants with risk indicators for hearing loss, before hospital discharge, with and without failure in UNHS. Methods: Prospective analytical observational study carried out in infants at risk for hearing loss and who underwent BAEP and ASSR in the same session. Results: 66 infants attempted the inclusion criteria, of both genders, the median age was 1.2 months, the mean gestational age was 31 weeks and the mean weight at birth was 1601 g. 53 (80%) infants, called G1, had normal BAEP, and 13 (20%) had abnormal BAEP, called G2. The electrophysiological thresholds of ASSR were statistically lower in infants of G1. Conclusion: There was a relationship between the findings of the BAEP and ASSR exams in infants at risk for hearing loss, when performed before hospital discharge. The median of the ASSR electrophysiological thresholds was lower for the infants who had normal BAEP and higher for those who had abnormal BAEP in the UNHSque tenían un PEATC normal y mayor para aquellos que tenían un PEATC alterado en CANU.

Introducción: El cribado auditivo neonatal universal (CANU) se realiza examinando el potencial evocado auditivo del tronco cerebral (PEAC), en la población con un indicador de riesgo de hipoacusia. La respuesta auditiva en estado estable (RAEE) es una técnica objetiva y automática para determinar los umbrales de audición por frecuencia específica, pero aún poco explorada antes del alta hospitalaria. Objetivo: analizar los resultados obtenidos en la exploración de PEAC y RAEE en lactantes con indicadores de riesgo de hipoacusia, antes del alta hospitalaria, con y sin fallo en CANU. Metodos: Estudio observacional analítico prospectivo realizado en lactantes con riesgo de hipoacusia a los que se les realizó PEATC y RAEE en una misma sesión. Resultados: Los criterios de inclusión cumplieron con 66 lactantes, de ambos sexos, edad media de 1,2 meses, edad gestacional media de 31 semanas, peso medio al nacer 1601 g. Tenían un PEATC normal, 53 (80%) lactantes, llamados G1 y 13 (20%) tenían un PEATC anormal, llamado G2. Los umbrales electrofisiológicos de RAEE fueron estadísticamente más bajos en lactantes del G1. Conclusión: Hubo una relación entre los hallazgos de los exámenes PEATC y RAEE en lactantes con riesgo de hipoacusia, cuando se realizaron antes del alta hospitalaria. La mediana de los umbrales electrofisiológicos de RAEE fue menor para los lactantes.

Humans , Male , Female , Infant , Audiometry, Evoked Response , Evoked Potentials, Auditory, Brain Stem , Neonatal Screening/methods , Patient Discharge , Prospective Studies , Risk Factors , Hearing Loss/diagnosis
Braz. j. otorhinolaryngol. (Impr.) ; 87(3): 290-297, May-Jun. 2021. tab, graf
Article in English | LILACS | ID: biblio-1285691


Abstract Introduction The cortical auditory evoked potential allows the possibility of objectively evaluating the entire auditory system, which is desirable in the pediatric population. Bone conduction auditory stimulation is recommended in the differential diagnosis of conductive hearing loss. However, there are not many studies of cortical auditory evoked potential using bone conduction. Objective The aim of this study was to characterize the response of cortical auditory evoked potential through bone conduction in normal-hearing neonates using an automated response analysis equipment. Methods This study included 30 normal-hearing neonates, without risk factors for hearing loss. The equipment used was the HEARlab automated response analysis and the cortical responses were evaluated at the frequencies of 500-4000 Hz through bone conduction, at intensity ranging from 0 to 60 dBnHL. The latencies and amplitudes were manually marked by experienced judges. Results Cortical auditory evoked potential responses were detected in 100% of the evaluated subjects and there was no difference regarding the cortical response of the neonates in relation to the variables of gender, ear and masking use. At an intensity of 60 dBnHL for the frequencies of 500, 1000, 2000 and 4000 Hz the latencies were 234; 241; 239 and 253 ms and the amplitudes were 15.6; 8.4; 6.2; 6.3 µV. The mean thresholds were 23.6; 28; 31 and 33.1 dBnHL, respectively. Conclusion It was possible to measure the cortical auditory evoked potential response in the neonatal population using bone vibrator as sound transducer and to draw the profile of the cortical auditory evoked potential latencies and amplitudes by frequencies at the intensity of 60 dBnHL and at the threshold.

Resumo Introdução O potencial evocado auditivo cortical traz a possibilidade de avaliar de forma objetiva todo o sistema auditivo, o que é desejável na população infantil. A estimulação auditiva por condução óssea é recomendada no diagnóstico diferencial da perda auditiva condutiva. Entretanto, não há muitos estudos de potencial evocado auditivo cortical com o uso do vibrador ósseo. Objetivo Caracterizar a resposta do potencial evocado auditivo cortical por vibrador ósseo em neonatos normo-ouvintes com equipamento de análise automática de resposta. Metodologia A pesquisa incluiu 30 neonatos normo-ouvintes e sem fator de risco para deficiência auditiva. Foi usado o equipamento de análise automática de resposta HEARlab e foram avaliadas as repostas corticais na frequências de 500 a 4000 Hz por vibrador ósseo, na intensidade de 0 a 60 dBnNA. As latências e amplitudes foram marcadas manualmente por juízes experientes. Resultados Foram detectadas respostas de potencial evocado auditivo cortical em 100% dos sujeitos avaliados. Não houve diferença na resposta cortical dos neonatos para as variáveis: sexo, orelha e uso do mascaramento. Para as frequências de 500, 1000, 2000 e 4000 Hz foram observadas as latências de 234; 241; 239 e 253 ms, as amplitudes de 15,6; 8,4; 6,2; 6,3 µV, na intensidade de 60 dBnNA, e os limiares médios de 23,6; 28; 31 e 33,1 dBnNA, respectivamente. Conclusão Foi possível obter a resposta do potencial evocado auditivo cortical na população neonatal com vibrador ósseo como transdutor de som e traçar o perfil das latências e amplitudes dos potencial evocado auditivo cortical por frequência nas intensidades de 60 dBnNA e no limiar.

Humans , Infant, Newborn , Child , Bone Conduction , Evoked Potentials, Auditory , Auditory Threshold , Acoustic Stimulation , Evoked Potentials, Auditory, Brain Stem , Hearing
Braz. j. otorhinolaryngol. (Impr.) ; 87(1): 19-27, Jan.-Feb. 2021. tab
Article in English | LILACS | ID: biblio-1153600


Abstract Introduction: Studies have demonstrated the ototoxic effects of antimalarial drugs in individuals who receive these drugs, but little is known regarding the toxicity of these drugs in the newborn auditory system when administered to the mother receive the drug during pregnancy. Objective: To verify the incidence of hearing loss in neonates who have no other associated risk indicators, born to mothers treated for malaria during pregnancy. Methods: A retrospective, quantitative cohort study was developed at Hospital de Base Dr. Ary Pinheiro and Clínica Limiar, both located in the municipality of Porto Velho (Rondônia). The sample consisted of 527 newborns divided into two groups: exposed to antimalarials drugs during pregnancy group (n = 32) and non-exposed group (n = 495). Data collection took place from September 2014 to December 2015, through an interview with the mothers and/or guardians of the newborn, through the newborns' and the mothers' records, and the neonatal hearing screening database of the above-mentioned institutions. Results: All the neonates in the exposed group, assessed through the recording of transient otoacoustic emissions associated with the automated brainstem auditory evoked potential test, underwent neonatal hearing screening in the first examination. Among the newborns in the non-exposed group, 30 showed failure and were retested. Of these, one continued to fail and was referred for diagnosis, in whom the results showed to be within the normal range. Among the neonates of the exposed group, infection with Plasmodium vivax was the most frequent, and was similarly distributed among the gestational trimesters, and chloroquine was the most commonly used antimalarial drug treatment more often given during the third trimester; these findings did not show any influence on the audiological findings of the studied neonates. Conclusion: The present study did not identify any cases of hearing loss in neonates born to mothers who used antimalarial drugs during gestation.

Resumo Introdução: Estudos comprovam os efeitos ototóxicos dos antimaláricos em pessoas que fazem uso destes medicamentos, porém pouco se sabe sobre a toxicidade destes fármacos no sistema auditivo de neonatos quando ingeridos pelas mães no período gestacional. Objetivo: Verificar a incidência de perda auditiva em neonatos de mães tratadas para malária durante a gestação sem outros indicadores de risco associados. Método: Estudo quantitativo, de coorte retrospectivo, desenvolvido no Hospital de Base Dr. Ary Pinheiro e na Clínica Limiar, ambos em Porto Velho (Rondônia). Compuseram a amostra 527 recém-nascidos divididos em dois grupos: grupo exposto (n = 32) e grupo não exposto (n = 495). A coleta de dados ocorreu de setembro de 2014 a dezembro de 2015, através de entrevista com as genitoras e/ou responsáveis pelo recém-nascido, investigação nos prontuários dos neonatos e das genitoras e no banco de dados da triagem auditiva neonatal das instituições supracitadas. Resultados: Todos os neonatos do grupo exposto, avaliados através do registro das emissões otoacústicas transientes associado a realização do potencial evocado auditivo de tronco encefálico automático passaram na triagem auditiva neonatal no primeiro exame. Já, entre os recém-nascidos do grupo não exposto, 30 apresentaram falha e foram retestados. Destes, um continuou falhando e foi encaminhado para diagnóstico, no qual foram evidenciados resultados dentro da normalidade. Nos neonatos do grupo exposto, a infecção pelo Plasmodium vivax foi a mais frequente, mostrando distribuição semelhante entre os trimestres gestacionais, sendo a cloroquina o antimalárico mais utilizado e o tratamento medicamentoso realizado mais frequentemente no terceiro trimestre, porém tais achados não mostraram influência sobre os achados audiológicos dos neonatos estudados. Conclusão: O presente estudo não identificou casos de perda auditiva nos neonatos de mães que utilizaram antimaláricos na gestação.

Humans , Female , Pregnancy , Hearing Loss/diagnosis , Hearing Loss/chemically induced , Hearing Loss/epidemiology , Antimalarials/adverse effects , Brazil , Retrospective Studies , Cohort Studies , Evoked Potentials, Auditory, Brain Stem , Neonatal Screening , Otoacoustic Emissions, Spontaneous , Hearing Tests
Rev. Assoc. Med. Bras. (1992) ; 67(1): 156-162, Jan. 2021. tab, graf
Article in English | LILACS | ID: biblio-1287783


SUMMARY OBJECTIVE: To verify the scientific evidence on the association between Autistic Spectrum Disorder and Central Auditory Processing Disorder in children, aiming to answer the following research question: What is the association between Autistic Spectrum and Alteration of Auditory Processing in Children? METHODS: Studies were chosen through the combination based on the Medical Subject Heading Terms (MeSH): [(auditory processing) and (children) and (autism) and (neurological disorders)]. The MEDLINE (PubMed), LILACS, and SciELO databases were used. The analyzed papers covered a ten-year period, from 2010 to 2020. We selected descriptive, cross-sectional, cohort, and case studies. We evaluated the quality of the papers, which had a minimum score of six in the modified scale of the literature. RESULTS: 126 papers were retrieved after the exclusion phase, and 17 of them followed the inclusion criteria. Only two papers answered the guiding question with audiological results. CONCLUSIONS: Patients diagnosed with autistic spectrum disorder may have disturbance central auditory processing, considering that changes were found both in absolute and interpeak latencies in the brainstem evoked response audiometry, as well as in latency and laterality of the N1c wave amplitude. In addition, there were changes in the assessment behavioral auditory processing. Thus, disturbance central auditory processing is common in children with autistic spectrum disorder.

Humans , Child , Autistic Disorder , Autism Spectrum Disorder , Auditory Perception , Cross-Sectional Studies , Evoked Potentials, Auditory, Brain Stem
CoDAS ; 33(1): e20180324, 2021. tab, graf
Article in Portuguese | LILACS | ID: biblio-1249593


RESUMO Objetivo Avaliar como as vias auditivas codificam e diferenciam as sílabas plosivas [ga],[da] e [ba], por meio do potencial evocado auditivo Frequency Following Response (FFR), nas crianças em desenvolvimento típico. Método Vinte crianças (6-12 anos) foram avaliadas por meio do FFR para estímulos [ga],[da] e [ba]. Os estímulos foram compostos por seis formantes, sendo diferenciados na transição F2 e F3 (porção transiente). Os demais formantes foram idênticos nas três sílabas (porção sustentada). Foram analisadas latências de 16 ondas que compõe a porção transiente do estímulo (<70ms) e latências de 21 ondas da porção sustentada (90-160ms) nas respostas neurais obtidas para cada uma das sílabas. Resultados As respostas eletrofisiológicas registradas por meio do FFR demonstraram que as latências da porção transiente da resposta neural foram diferentes nas três silabas evocadas. Além disso, os valores de latência das ondas da porção transiente foram aumentando progressivamente, sendo [ga]<[da]<[ba]. Já na porção sustentada da resposta, não houve diferenças significantes nas latências das ondas que compõe essa porção. Conclusão O FFR mostrou-se uma ferramenta eficiente na investigação da discriminação subcortical de diferenças acústicas dos sons de fala, uma vez que demonstrou diferentes resposta eletrofisiológica para três silabas evocadas. Na porção transiente (consoantes) foram observadas mudanças de latência e na porção sustentada (vogal) não houve diferenças entre as latências para os três estímulos. Esses resultados demonstram a capacidade neural de distinção entre características acústicas dos estímulos [ga],[da],[ba].

ABSTRACT Purpose To evaluate how the auditory pathways encode and discriminate the plosive syllables [ga], [da] and [ba] using the auditory evoked Frequency-following Response (FFR) in children with typical development. Methods Twenty children aged 6-12 years were evaluated using the FFR for the [ga], [da] and [ba] stimuli. The stimuli were composed of six formants and were differentiated in the F2 to F3 transition (transient portion). The other formants were identical in the three syllables (sustained portion). The latencies of the 16 waves of the transient portion (<70ms) and of the 21 waves of the sustained portion (90-160ms) of the stimuli were analyzed in the neural responses obtained for each of the syllables. Results The transient portion latencies were different in the three syllables, indicating a distinction in the acoustic characteristics of these syllables through their neural representations. In addition, the transient portion latencies progressively increased in the following order: [ga] <[da] <[ba], whereas no significant differences were observed in the sustained portion. Conclusion The FFR proved to be an efficient tool to investigate the subcortical acoustic differences in speech sounds, since it demonstrated different electrophysiological responses for the three evoked syllables. Changes in latency were observed in the transient portion (consonants) but not in the sustained portion (vowels) for the three stimuli. These results indicate the neural ability to distinguish between acoustic characteristics of the [ga], [da] and [ba] stimuli.

Humans , Child , Speech Perception , Phonetics , Acoustic Stimulation , Acoustics , Evoked Potentials, Auditory, Brain Stem , Hearing
Braz. j. med. biol. res ; 54(11): e11503, 2021. graf
Article in English | LILACS | ID: biblio-1285661


The mixture of ketamine and xylazine is widely used for the auditory brainstem response (ABR) measurement. Esketamine is twice as potent as ketamine. Our objective was to assess the influence of esketamine in mice undergoing cochlear function measurement including ABR and distortion product otoacoustic emission (DPOAE) measurement. C57Bl/6J mice were treated with an equivalent dose of analgesia and received either a single intraperitoneal (ip) injection of 100 mg/kg ketamine and 25 mg/kg xylazine or 50 mg/kg esketamine and 25 mg/kg xylazine. Hearing thresholds, peak latencies of waves I and V, and DPOAE thresholds were recorded. Time to loss of righting and time to regain righting were also assessed. We found that hearing thresholds, the peak latencies of waves I and V, and DPOAE thresholds were similar between the two groups (all P>0.05). Time to regain righting was significantly shorter in the esketamine group (P<0.001) than in the ketamine group. We concluded that when using equivalent doses of analgesia, esketamine may be an ideal substitute for ketamine during cochlear function test.

Animals , Rabbits , Ketamine , Xylazine , Evoked Potentials, Auditory, Brain Stem , Otoacoustic Emissions, Spontaneous
Clinics ; 76: e2944, 2021. tab, graf
Article in English | LILACS | ID: biblio-1345817


OBJECTIVES: To analyze central auditory maturation in term and preterm infants during the first 3 months of life by comparing the latency and amplitude of cortical auditory-evoked potential at different frequencies. METHODS: In this study, 17 term and 18 preterm infants were examined; all had tested positive on the neonatal hearing screening test. Cortical auditory potential was investigated during the first and third months of life. The response of the cortical auditory-evoked potential was investigated at frequencies of 500, 1000, 2000, and 4000 Hz. The latency and amplitude of the cortical response were automatically detected and manually analyzed by three researchers with experience in electrophysiology. The results were compared using analysis of variance and the Bonferroni test. A significance level of 5% was used for all analyses. RESULTS: Latency values of cortical auditory-evoked potential in the first month of birth were significantly higher than those in the third month, and latency values of the preterm group were higher than those of the term group, regardless of the frequency and time of evaluation. In general, the latency of the cortical auditory-evoked potential was higher at high frequencies. Amplitude values in the third month of life were significantly higher than those in the first month for term and preterm infants. CONCLUSION: Central auditory maturation was observed in both groups but with different results between those born at term and preterm, with latencies of cortical auditory-evoked potential higher for the preterm group and at high frequencies.

Humans , Infant, Newborn , Infant , Infant, Premature , Evoked Potentials, Auditory, Brain Stem , Biomarkers , Neonatal Screening , Evoked Potentials, Auditory
Clinics ; 76: e2085, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153963


OBJECTIVES: We aimed to evaluate the effectiveness of a binaural auditory training program with vocal duets by comparing skills through outcomes from behavioral and electrophysiological assessment instruments at three moments: before the intervention, moment one (M1); immediately after training, moment two (M2); and 3 months after, moment three (M3). METHODS: This interventional, longitudinal, prospective, and uncontrolled study was approved by our Research Ethics Committee. Binaural auditory training with vocal duets (ATVD) was applied in 10 adults with normal audiometric thresholds and auditory processing disorders. ATVD used four different vocals of a public domain song sung in a cappella as stimuli. Participants were asked to register any perceived difference in frequency for each syllable of the song during 30-minute sessions twice a week. The number of sessions required ranged from 12 (6 hours) to 20 (10 hours). RESULTS: Regarding behavioral tests, the dichotic consonant-vowel test showed significant evidence of an improved advantage in the left ear (LE) in the non-forced condition and a significant reduction in the number of errors at M2 and M3 in the forced left condition. The speech-in-noise test and frequency pattern test showed a significant reduction in impaired results at M2 and M3. Electrophysiological results showed a significant increase in the LE amplitude in the P3 long-latency auditory evoked potentials test, as well as a decrease in the auditory brainstem response test (III-V and I-V inter-peak latencies in the right ear and wave I and I-III inter-peak latencies in LE). CONCLUSION: The effectiveness of ATVD was evidenced, and the results were maintained after 3 months.

Humans , Adult , Auditory Perceptual Disorders , Evoked Potentials, Auditory , Speech , Acoustic Stimulation , Prospective Studies , Evoked Potentials, Auditory, Brain Stem , Noise
Article in Chinese | WPRIM | ID: wpr-879884


OBJECTIVE@#To study brainstem auditory evoked potential (BAEP) in neonates with hyperbilirubinemia using short auditory stimuli (60 dBnHL), and to investigate the differences in the inter-aural latency difference (ILD) of wave V between neonates with different total serum bilirubin (TSB) levels.@*METHODS@#A prospective study was conducted in neonates with hyperbilirubinemia who were admitted to the Department of Neonatology, Yuhuan People's Hospital of Zhejiang Province, from May 2019 to October 2020. The neonates were divided into a severe group (@*RESULTS@#Compared with the mild group, the severe group had significantly higher proportions of neonates with abnormal hearing threshold and abnormal ILD (@*CONCLUSIONS@#Serum bilirubin in neonates affects the ILD of BAEP wave V, especially in those with severe hyperbilirubinemia. ILD at the optimal cut-off value of ≥0.4 ms shows potential value in the diagnosis of hearing impairment caused by neonatal hyperbilirubinemia.

Bilirubin , Evoked Potentials, Auditory, Brain Stem , Hearing Loss , Humans , Hyperbilirubinemia , Hyperbilirubinemia, Neonatal , Infant, Newborn , Prospective Studies
J. pediatr. (Rio J.) ; 96(3): 386-392, May-June 2020. graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1135026


Abstract Objectives: This study aimed to analyze the neural encoding of verbal and nonverbal stimuli in individuals with autism spectrum disorder using brainstem auditory evoked potentials. Methodology: Thirty individuals between 7 and 12 years of age and of both genders participated in this study. Fifteen were diagnosed with autism spectrum disorder, and 15 had typical development. All subjects had normal hearing and no other impairments. An electrophysiological hearing assessment was performed using brainstem auditory evoked potentials with click and speech stimuli. Results: In the brainstem auditory evoked potentials with click stimuli, the mean wave I latency was longer for the right ear in both groups, and interpeak intervals III-V were greater for the individuals with autism spectrum disorder. For brainstem auditory evoked potentials with speech stimuli, wave V latency was shorter in individuals with autism spectrum disorder. Conclusion: These data suggest that individuals with autism spectrum disorder may have a dysfunction of the central auditory nervous system for nonverbal stimuli and faster neural encoding of the initial part of the verbal stimulus, suggesting hypersensitivity to complex sounds such as speech.

Resumo Objetivos: Este estudo visou analisar a codificação neural de estímulos verbais e não verbais em indivíduos com transtorno do espectro do autismo com o uso de potenciais evocados auditivos de tronco encefálico. Metodologia: Participaram 30 indivíduos entre sete e 12 anos e de ambos os sexos; 15 foram diagnosticados com transtorno do espectro do autismo e 15 apresentaram desenvolvimento típico. Todos os indivíduos apresentaram audição normal e nenhuma outra alteração. Foi feita uma avaliação eletrofisiológica da audição com o uso dos potenciais evocados auditivos de tronco encefálico com estímulos de clique e fala. Resultados: Nos potenciais evocados auditivos de tronco encefálico com estímulos de clique, a média do valor de latência da onda I foi maior para o ouvido direito nos dois grupos e os intervalos interpicos III-V foram maiores para os indivíduos com transtorno do espectro do autismo. Para os potenciais evocados auditivos de tronco encefálico com estímulos de fala, a latência da onda V foi menor nos indivíduos com transtorno do espectro do autismo. Conclusão: Nossos dados sugerem que os indivíduos com transtorno do espectro do autismo podem ter uma disfunção do sistema nervoso auditivo central para estímulos não verbais e codificação neural mais rápida da parte inicial dos estímulos verbais, o que sugere hipersensibilidade a sons complexos, como a fala.

Humans , Male , Female , Child , Evoked Potentials, Auditory, Brain Stem , Autism Spectrum Disorder , Physical Examination , Acoustic Stimulation , Hearing Tests
Braz. j. otorhinolaryngol. (Impr.) ; 86(6): 793-811, Nov.-Dec. 2020. tab, graf
Article in English | LILACS | ID: biblio-1142608


Abstract Introduction: The brainstem auditory evoked potential with speech stimulus, BAEP-speech, has been applied to observe how speech sounds are manifested in the brainstem. This tool can be used in children to assess central auditory processing, allowing preventive and early interventions. Objective: To assess the results found in the brainstem auditory evoked potential with speech stimulus in the pediatric population with and without oral language disorders, through a systematic literature review. Methods: The search was carried out in the scientific databases Portal BVS, Pubmed, Lilacs, Medline, Scielo and Web of Science,, DissOnline, OpenDoar, OAIster and The New York Academy of Medicine. A systematic literature review was performed using the descriptors: auditory evoked potentials, children and their synonyms, combined by the Boolean operators AND and OR. The search filter "age: child" was used. The studies were independently read by peers and, in case of disagreement regarding the inclusion of studies, a third researcher was consulted. Original case-control articles that performed BAEP-speech without competitive noise, carried out in the pediatric population without and with oral language disorders, were included. Result: 14 articles published between 2008 and 2019 were included in this review. Methodological variability was observed in the exam, with the syllable / da / being the most frequently used as the stimulus. When performing the average of the groups, it was observed that the population with specific language disorders showed greater latency delays in the sustained portion, lower amplitude values and VA complex slope. The group with phonological disorders had higher values in the transient portion of the responses. Conclusion: Children with language disorders of different etiologies have different patterns of BAEP-speech responses when compared to children with typical development.

Resumo Introdução: O potencial evocado auditivo de tronco encefálico com estímulo de fala (PEATE-fala) tem sido aplicado para observar como os sons da fala se manifestam no tronco encefálico. Essa ferramenta pode ser usada em crianças na avaliação do processamento auditivo central, permite intervenções preventivas e precoces. Objetivo: Conhecer os resultados encontrados no potencial evocado auditivo de tronco encefálico com estímulo de fala na população pediátrica com e sem transtornos de linguagem oral, por meio de revisão sistemática da literatura. Método: As buscas foram feitas nas bases de dados científicos Portal BVS, Pubmed, Lilacs, Medline, Scielo e Web of Science,, DissOnline, OpenDoar, OAIster e The New York Academy of Medicine. Foi feita revisão sistemática da literatura, com os descritores auditory evoked potentials, children e seus sinônimos, combinados pelos operadores booleanos AND e OR. Foi usado o filtro de pesquisa "idade: criança". A leitura dos estudos foi feita por pares de forma independente e em caso de discordância na inclusão de estudos um terceiro pesquisador foi consultado. Foram incluídos artigos originais do tipo caso-controle que fizeram o PEATE-fala sem ruído competitivo na população pediátrica sem e com transtornos de linguagem oral. Resultado: Foram incluídos 14 artigos publicados entre 2008 e 2019 na presente revisão. Foi observada variabilidade metodológica na realização do exame, a sílaba /da/ foi a mais usada para estimulação. Ao se fazerem médias dos grupos, observou-se que a população com distúrbio específico de linguagem apresentou maiores atrasos de latência na porção sustentada, menores valores de amplitude e slope do complexo VA. O grupo com transtorno fonológico obteve maiores valores na porção transiente das respostas. Conclusão: Crianças com alterações de linguagem de diferentes etiologias apresentam padrões de respostas do PEATE-fala distintos quando comparadas às crianças com desenvolvimento típico.

Humans , Child , Speech Perception , Evoked Potentials, Auditory, Brain Stem , Speech , Acoustic Stimulation , Evoked Potentials, Auditory , Language Development Disorders
Braz. j. otorhinolaryngol. (Impr.) ; 86(6): 687-695, Nov.-Dec. 2020. tab, graf
Article in English | LILACS | ID: biblio-1142606


Abstract Introduction: The study of the threshold level of cortical auditory response in adults has been investigated in previous studies. Due to maturational issues, little is known about these responses in neonates. Technological advances with automatic analysis devices now allow investigation in specific populations. Thus, new studies are needed to establish the feasibility of using this auditory potential to identify the lowest levels of responses in children. Objective: Verify and compare latency and amplitude in 80 dBnNA and the minimum level of cortical auditory response in term and preterm neonates. Methods: A cross-sectional, comparative study involving 59 neonates, 35 full-term births and 24 preterm births, with positive results in the Neonatal Hearing Screening. The Hearlab system was used to investigate the P1i auditory potential with tone burst stimulus at frequencies of 500, 1000, 2000 and 4000 Hz. The minimum response level search ranged from 80 to 0 dBNA and was detected automatically. The results were compared between groups, evaluating the latency and amplitude in 80 dBNA and the minimum level of cortical auditory response. Results: The mean values obtained for the minimum level of cortical auditory response in term group were 26 ± 8.81; 26.14 ± 6.97; 29 ± 7.65 and 29.43 ± 7.04 dBNA and for preterm neonates of 31.96 ± 10.41; 34.13 ± 11.34; 33.64 ± 11.03 and 37.73 ± 11.92 dBNA, for the frequencies of 500, 1000, 2000 and 4000 Hz, respectively. There was a difference between groups for the latency of P1i at 4000 Hz and the minimum response levels at 500, 1000 and 4000 Hz, with higher values for preterm infants. Conclusion: It was possible to obtain latency and amplitude values at 80 dBnNA and the minimum level of cortical response in term and preterm newborns, with different results between groups, with higher values in those born preterm.

Resumo Introdução: A investigação do nível mínimo de resposta auditiva cortical tem sido alvo de diferentes estudos em adultos. Devido a questões de maturação, pouco se sabe sobre essas respostas em recém-nascidos. Com o avanço tecnológico, dispositivos de análise automática surgiram com o objetivo de retomar essa avaliação em populações específicas. Assim, novos estudos são necessários para verificar a viabilidade do uso desse potencial auditivo na obtenção de níveis mínimos de respostas na criança. Objetivo: Verificar e comparar latência e amplitude em 80 dBnNA e o nível mínimo de resposta auditiva cortical em recém-nascidos a termo e pré-termo. Método: Estudo transversal, comparativo, envolvendo 59 neonatos, 35 nascidos a termo e 24 pré-termos, com resultados positivos na triagem auditiva neonatal. O sistema Hearlab foi utilizado para investigar o potencial auditivo P1i com estímulo tone burst nas frequências de 500, 1000, 2000 e 4000 Hz. A busca do nível mínimo de resposta variou de 80 a 0 dBNA e foi detectado automaticamente. Os resultados foram comparados entre os grupos, avaliando a latência e amplitude em 80 dBNA e o nível mínimo de resposta auditiva cortical. Resultados: Os valores médios obtidos para o nível mínimo de resposta auditiva cortical no grupo nascido a termo foram 26 ± 8,81; 26,14 ± 6,97; 29 ± 7,65 e 29,43 ± 7,04 dBNA e para recém-nascidos pré-termos foram de 31,96 ± 10,41; 34,13 ± 11,34; 33,64 ± 11,03 e 37,73 ± 11,92 dBNA, para as frequências de 500, 1000, 2000 e 4000 Hz, respectivamente. Houve diferenc¸a entre os grupos para a latência de P1i em 4000 Hz e os níveis mínimos de resposta em 500, 1000 e 4000 Hz, com valores maiores em Pré-termos. Conclusão: Foi possível obter valores de latência e amplitude em 80 dBnNA e o nível mínimo de resposta cortical em recém-nascidos a termo e Pré-termos, com resultados diferentes entre osgrupos, com valores maiores em pré-termos.

Humans , Infant, Newborn , Infant, Premature , Evoked Potentials, Auditory , Acoustic Stimulation , Cross-Sectional Studies , Evoked Potentials, Auditory, Brain Stem , Hearing
J. pediatr. (Rio J.) ; 96(2): 202-209, Mar.-Apr. 2020. tab
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1135010


Abstract Objective: This study analyzed the relationship between latent iron deficiency evaluated by ferritin, and the myelination of the central nervous system evaluated through the brainstem evoked response audiometry test. Method: A total of 109 full-term newborns, born without anemia and risk factor for hearing deficiency, were enrolled. After delivery, umbilical cord blood was collected to determine ferritin and hematocrit levels. The brainstem evoked response audiometry test was carried out in the first 28 days of life. Analysis was performed between the control group (n = 71) with ferritin greater than 75 ng/mL, and the latent iron deficiency group (n = 38) with ferritin between 11 and 75 ng/mL. Results were presented as mean ± standard deviation. Statistical analysis was performed using GraphPad prism7 and SPSS with a significance level of 5%. Results: A significant higher V-wave (p = 0.02) and interpeak intervals I-III (p = 0.014), I-V (p = 0.0003), and III-V (p = 0.0002) latencies were found in the latent iron deficiency group, as well as a significant inversely proportional correlation between ferritin and the same wave and intervals (p = 0.003, p = 0.0013, p = 0.0002, p = 0.009, respectively). Multiple correlation analysis showed a significant correlation of latent iron deficiency with all interpeak intervals, even taking into account newborn gestational age. Conclusion: Iron deficiency anemia is a prevalent pathology; this study showed auditory delayed maturation associated to intrauterine iron deficiency, even in its latent form. This reinforces the importance of adopting effective measures, on a global scale, to prevent and treat this pathology in different life periods, especially in the most vulnerable population.

Resumo Objetivo Este estudo analisou a relação entre deficiência de ferro latente avaliada pela ferritina e a mielinização do sistema nervoso central avaliada pelo teste de Potenciais Evocados Auditivos de Tronco Encefálico. Método Foram incluídos no estudo 109 recém-nascidos a termo, nascidos sem anemia e fator de risco para deficiência auditiva. Após o parto, o sangue do cordão umbilical foi coletado para determinar os níveis de ferritina e hematócrito. O teste de Potenciais Evocados Auditivos de Tronco Encefálico foi realizado nos primeiros 28 dias de vida. A análise foi realizada entre o grupo controle (n = 71) com ferritina acima de 75 ng/mL e o grupo com deficiência de ferro latente (n = 38) com ferritina entre 11 e 75 ng/mL. Os resultados foram apresentados como média ± desvio-padrão. A análise estatística foi realizada utilizando o software GraphPad prism7 e SPSS com nível de significância de 5%. Resultados Latências significativamente maiores da onda V (p = 0,02) e dos intervalos interpicos I-III (p = 0,014), I-V (p = 0,0003) e III-V (p = 0,0002) foram encontradas no grupo de deficiência de ferro latente, assim como uma correlação significativa inversamente proporcional entre a ferritina e a mesma onda e intervalos (p = 0,003, p = 0,0013, p = 0,0002, p = 0,009, respectivamente). A análise de correlação múltipla mostrou uma correlação significativa da deficiência de ferro latente com todos os intervalos interpicos, mesmo se levarmos em consideração a idade gestacional do recém-nascido. Conclusão A anemia ferropriva é uma patologia prevalente e este estudo demonstrou maturação auditiva tardia associada à deficiência intrauterina de ferro, mesmo em sua forma latente. Isso reforça a importância da adoção de medidas efetivas, em escala global, para prevenir e tratar essa patologia em diferentes períodos da vida, principalmente na população mais vulnerável.

Humans , Infant, Newborn , Anemia, Iron-Deficiency , Evoked Potentials, Auditory, Brain Stem , Gestational Age , Term Birth , Ferritins , Fetal Blood
Braz. j. otorhinolaryngol. (Impr.) ; 86(2): 209-216, March-Apr. 2020. tab, graf
Article in English | LILACS | ID: biblio-1132583


Abstract Introduction: Deficient auditory processing can cause problems with speech perception and affect the development and evolution of reading skills. The efferent auditory pathway has an important role in normal auditory system functions like speech-in-noise perception, but there is still no general agreement on this. Objective: To study the performance of the efferent auditory system in a group of children with reading impairment in comparison with normal reading and evaluation of its relationship with speech-in-noise perception. Methods: A total of 53 children between the ages of 8-12 years were selected for the study of which 27 were with reading impairment and 26 were normal reading children. Transient evoked otoacoustic emissions suppression and auditory recognition of words-in-noise test were performed for all the children. Results: The average amplitude of transient evoked otoacoustic emissions suppression showed a significant difference between the two groups in the right (p = 0.004) and in the left ear (p = 0.028). Assessment of the relationship between transient evoked otoacoustic emissions suppression and monaural auditory recognition of words-in-noise scores showed a significant moderate negative relationship only in the right ear (p = 0.034, r = −0.41) of the normal reading children. Binaural auditory recognition of words-in-noise scores were significantly correlated with the amplitude of transient evoked otoacoustic emissions suppression in the right ear (p < 0.001, r = −0.75) and in the left ear (p < 0.001, r = −0.64) of normal reading children. In the reading impaired group, ?a weaker correlation was observed between binaural auditory recognition of words-in-noise scores and transient evoked otoacoustic emissions suppression in the right (p = 0.003, r = −0.55) and in the left ear (p = 0.012, r = −0.47). Conclusions: Transient evoked otoacoustic emissions suppression pattern in the reading impaired group was different compared with normal reading children, and this difference could be related to efferent system performance. Words-in-noise scores in children with impaired reading were lower than in normal reading children. In addition, a relationship was found between transient evoked otoacoustic emissions suppression and words-in-noise scores in both normal and impaired reading children.

Resumo Introdução: O processamento auditivo deficiente pode causar problemas na percepção da fala e afetar o desenvolvimento e a evolução das habilidades de leitura. A via auditiva eferente tem um papel importante nas funções do sistema auditivo normal, como a percepção da fala no ruído, mas ainda não há um consenso sobre isso. Objetivo: Estudar o desempenho do sistema auditivo eferente em um grupo de crianças com dificuldade de leitura em comparação às com leitura normal e avaliação de sua relação com a percepção da fala no ruído. Método: Foram selecionadas para o estudo 53 crianças entre oito e 12 anos, das quais 27 tinham dificuldade de leitura e 26 apresentavam leitura normal. A avaliação por emissões otoacústicas evocadas transientes e o teste auditory recognition of words-in-noise foram feitos em todas as crianças. Resultados: A amplitude média da supressão das emissões otoacústicas evocadas transientes mostrou diferença significante entre os dois grupos na orelha direita (p = 0,004) e esquerda (p = 0,028). A avaliação da relação entre a supressão das emissões otoacústicas evocadas transientes e os escores monoaurais do teste auditory recognition of words-in-noise mostrou uma relação negativa moderadamente significante apenas na orelha direita (p = 0,034, r = -0,41) das crianças com leitura normal. Os escores binaurais do auditory recognition of words-in-noise foram significantemente correlacionados com a amplitude de supressão das emissões otoacústicas evocadas transientes na orelha direita (p < 0,001, r = -0,75) e na orelha esquerda (p < 0,001, r = -0,64) das crianças com leitura normal. No grupo com dificuldade de leitura, uma correlação mais fraca foi observada entre os escores binaurais do auditory recognition of words-in-noise e supressão das emissões otoacústicas evocadas transientes, na orelha direita (p = 0,003, r = -0,55) e na esquerda (p = 0,012, r = -0,47). Conclusões: O padrão de supressão das emissões otoacústicas evocadas transientes no grupo com dificuldade de leitura foi diferente em comparação com as crianças com leitura normal e essa diferença pode estar relacionada ao desempenho do sistema eferente. Os escores de palavras no ruído em crianças com dificuldade de leitura foram menores do que nas crianças com leitura normal. Além disso, foi encontrada uma relação entre a supressão das emissões otoacústicas evocadas transientes e os escores de palavras no ruído tanto em crianças com leitura normal quanto nas com dificuldade de leitura.

Humans , Male , Female , Child , Auditory Pathways/physiology , Speech Perception/physiology , Evoked Potentials, Auditory, Brain Stem/physiology , Otoacoustic Emissions, Spontaneous/physiology , Dyslexia/physiopathology , Efferent Pathways/physiology , Acoustic Stimulation , Case-Control Studies , Noise
Braz. j. otorhinolaryngol. (Impr.) ; 86(2): 191-200, March-Apr. 2020. tab, graf
Article in English | LILACS | ID: biblio-1132572


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.

Humans , Male , Female , Infant, Newborn , Reaction Time/physiology , Speech/physiology , Acoustic Stimulation/methods , Evoked Potentials, Auditory, Brain Stem/physiology , Neonatal Screening
Int. arch. otorhinolaryngol. (Impr.) ; 24(1): 47-52, Jan.-Mar. 2020. graf
Article in English | LILACS | ID: biblio-1090559


Abstract Introduction Cisplatin damages the auditory system and is related to the generation of free radicals. Glutathione peroxidase is an endogenous free radicals remover. Objective To investigate the mechanisms involved in otoprotection by N-acetylcys- teine through the expression of glutathione peroxidase in outer hair cells from rats treated with cisplatin. Methods Male Wistar rats were intraperitoneally injected with cisplatin (8 mg/Kg) and/or received oral administration by gavage of N-acetylcysteine (300 mg/Kg) for 3 consecutive days. On the 4th day, the animals were euthanized and beheaded. The tympanic bullae were removed and prepared for scanning electron microscopy and Results Among the groups exposed to ototoxic doses of cisplatin, there was an increase in glutathione peroxidase immunostaining in two groups, the one exposed to cisplatin alone, and the group exposed to both cisplatin and N-acetylcysteine. Conclusion The expression of glutathione peroxidase in the outer hair cells of rats exposed to cisplatin showed the synthesis of this enzyme under cellular toxicity conditions.

Animals , Male , Acetylcysteine/therapeutic use , Free Radical Scavengers/therapeutic use , Cisplatin/toxicity , Oxidative Stress/drug effects , Antineoplastic Agents/toxicity , Acetylcysteine/metabolism , Acetylcysteine/pharmacology , Microscopy, Electron, Scanning , Evoked Potentials, Auditory, Brain Stem , Free Radical Scavengers/metabolism , Free Radical Scavengers/pharmacology , Fluorescent Antibody Technique , Cisplatin/therapeutic use , Rats, Wistar , Cochlea/anatomy & histology , Cochlea/drug effects , Free Radicals , Glutathione Peroxidase/metabolism , Hearing Loss, Sensorineural/prevention & control