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1.
Clin Interv Aging ; 15: 927-935, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606634

RESUMO

Purpose: The objective of the study was to identify subjects presenting hearing deficits, specifically age-related hearing losses (ARHL), via objective assessment methodologies. Materials and Methods: Initially, 259 subjects (165 men, 94 women) were enrolled in the study. After the application of inclusion criteria, the final number was reduced to 88 subjects (49.8 ± 19.1 ys) subdivided into 64 normal and 83 ARHL cases. The subjects were assessed with traditional audiometry tests and with transiently evoked otoacoustic emissions (TEOAEs). Since each ear has its own acoustic signature, the TEOAE analyses were conducted in terms of ears and not subjects. The TEOAE data were processed by traditional and recurrence quantification analyses, leading to the estimation of the WWR (whole waveform reproducibility) and the new RAD2D (2-dimensional radius) parameters. A plot of WWR vs RAD2D was used to optimize the classification of the cases presenting ARHL. Results: By using a WWR value of 70% as a classifier, the sensitivity of TEOAEs was estimated as 75.9% and the specificity as 89.1%. By using the RAD2D parameter (with a cut-off value of 1.78), a sensitivity value of 80.7% and a specificity value of 71.9% were obtained. When both parameters were used, a sensitivity value of 85.5% and a specificity value of 92.2% were estimated. In the latter classification paradigm, the number of false negatives decreased from 20 to 12 out of 83 ears (14%). Conclusion: In adult hearing screening assessments, the proposed method optimizes the identification of subjects with a hearing impairment correlated to the presence of age-related hearing loss.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Transtornos da Audição/diagnóstico , Emissões Otoacústicas Espontâneas/fisiologia , Estimulação Acústica , Idoso , Audiometria , Limiar Auditivo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
2.
Ann Otol Rhinol Laryngol ; 129(11): 1110-1119, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32500717

RESUMO

OBJECTIVES: Tinnitus is a common and distressing otologic symptom, with various probable pathophysiologic mechanisms, such as an imbalance between excitatory and inhibitory mechanisms. Acamprosate, generally used to treat alcoholism, is a glutaminergic antagonist and GABA agonist suggested for treating tinnitus. Thus, we aimed to evaluate the efficacy and safety of acamprosate in the treatment of tinnitus. METHODS: The current randomized-controlled trial study included 20 subjects with chronic tinnitus. After performing psycho-acoustic, psychometric and electrophysiological evaluations, all studied tinnitus subjects were randomly divided into two groups of acamprosate and placebo. The first group received oral acamprosate (two tablets of 333 mg/d, three times a day), whereas the second group was given placebo treatment (two tablets, three times a day). After the first 30 days, all evaluations were repeated for the studied groups just in the same manner before the study. Subsequently, the final results of each evaluation were compared together with the baseline values. RESULTS: Nine studied subjects randomly received acamprosate, whereas eleven others received a placebo. There was no significant improvement in the psycho-acoustic tests, except a decrease was observed in the pitch match of tinnitus (P = .039). For those subjects who were receiving acamprosate, a significant reduction was observed in tinnitus handicap inventory (P = .006), tinnitus questionnaire scores (P = .007), and the visual analog scores (P = .007) compared to the placebo group. There was a significant reduction in Action Potential latency (P = .048) as well as an increase in the amplitude of distortion product otoacoustic emissions at 4 kHz (P = .048). CONCLUSIONS: The study results indicated a subjective relief of tinnitus as well as some degree of the electrophysiological improvement at the level of the cochlear and the distal portion of the auditory nerve among the subjects who received the acamprosate. CLINICAL TRIAL REGISTRATION CODE: IRCT2013121115751N1.


Assuntos
Acamprosato/administração & dosagem , Emissões Otoacústicas Espontâneas/fisiologia , Zumbido/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Dissuasores de Álcool/administração & dosagem , Audiometria de Tons Puros , Doença Crônica , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Estudos Retrospectivos , Zumbido/fisiopatologia , Adulto Jovem
3.
Proc Natl Acad Sci U S A ; 117(20): 11109-11117, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358189

RESUMO

Outer hair cells (OHCs) play an essential role in hearing by acting as a nonlinear amplifier which helps the cochlea detect sounds with high sensitivity and accuracy. This nonlinear sound processing generates distortion products, which can be measured as distortion-product otoacoustic emissions (DPOAEs). The OHC stereocilia that respond to sound vibrations are connected by three kinds of extracellular links: tip links that connect the taller stereocilia to shorter ones and convey force to the mechanoelectrical transduction channels, tectorial membrane-attachment crowns (TM-ACs) that connect the tallest stereocilia to one another and to the overlying TM, and horizontal top connectors (HTCs) that link adjacent stereocilia. While the tip links have been extensively studied, the roles that the other two types of links play in hearing are much less clear, largely because of a lack of suitable animal models. Here, while analyzing genetic combinations of tubby mice, we encountered models missing both HTCs and TM-ACs or HTCs alone. We found that the tubby mutation causes loss of both HTCs and TM-ACs due to a mislocalization of stereocilin, which results in OHC dysfunction leading to severe hearing loss. Intriguingly, the addition of the modifier allele modifier of tubby hearing 1 in tubby mice selectively rescues the TM-ACs but not the HTCs. Hearing is significantly rescued in these mice with robust DPOAE production, indicating an essential role of the TM-ACs but not the HTCs in normal OHC function. In contrast, the HTCs are required for the resistance of hearing to damage caused by noise stress.


Assuntos
Células Ciliadas Auditivas Externas/fisiologia , Ruído , Emissões Otoacústicas Espontâneas/fisiologia , Som , Estimulação Acústica , Animais , Células Ciliadas Auditivas Externas/citologia , Perda Auditiva , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Modelos Animais , Emissões Otoacústicas Espontâneas/genética , Estereocílios/fisiologia , Membrana Tectorial
4.
Proc Natl Acad Sci U S A ; 117(21): 11811-11819, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393641

RESUMO

"Growing old" is the most common cause of hearing loss. Age-related hearing loss (ARHL) (presbycusis) first affects the ability to understand speech in background noise, even when auditory thresholds in quiet are normal. It has been suggested that cochlear denervation ("synaptopathy") is an early contributor to age-related auditory decline. In the present work, we characterized age-related cochlear synaptic degeneration and hair cell loss in mice with enhanced α9α10 cholinergic nicotinic receptors gating kinetics ("gain of function" nAChRs). These mediate inhibitory olivocochlear feedback through the activation of associated calcium-gated potassium channels. Cochlear function was assessed via distortion product otoacoustic emissions and auditory brainstem responses. Cochlear structure was characterized in immunolabeled organ of Corti whole mounts using confocal microscopy to quantify hair cells, auditory neurons, presynaptic ribbons, and postsynaptic glutamate receptors. Aged wild-type mice had elevated acoustic thresholds and synaptic loss. Afferent synapses were lost from inner hair cells throughout the aged cochlea, together with some loss of outer hair cells. In contrast, cochlear structure and function were preserved in aged mice with gain-of-function nAChRs that provide enhanced olivocochlear inhibition, suggesting that efferent feedback is important for long-term maintenance of inner ear function. Our work provides evidence that olivocochlear-mediated resistance to presbycusis-ARHL occurs via the α9α10 nAChR complexes on outer hair cells. Thus, enhancement of the medial olivocochlear system could be a viable strategy to prevent age-related hearing loss.


Assuntos
Envelhecimento/fisiologia , Cóclea , Células Ciliadas Auditivas Externas , Presbiacusia , Complexo Olivar Superior , Animais , Cóclea/fisiologia , Cóclea/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Retroalimentação Fisiológica/fisiologia , Células Ciliadas Auditivas Externas/citologia , Células Ciliadas Auditivas Externas/fisiologia , Camundongos , Emissões Otoacústicas Espontâneas/fisiologia , Presbiacusia/fisiopatologia , Presbiacusia/prevenção & controle , Complexo Olivar Superior/citologia , Complexo Olivar Superior/fisiologia
5.
Trop Doct ; 50(3): 246-248, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32290759

RESUMO

Auditory neuropathy spectrum disorder (ANSD) can cause significant hearing impairment; it occurs when there is intact outer hair cell function in the inner ear, with a dyssynchronous neural response, thought to be due to dysfunction of the inner hair cells (IHCs), the synapse of the IHCs and the auditory nerve, or of the auditory nerve itself. This case report describes the onset of ANSD in a Malawian child after severe malaria treated with quinine. Diagnosis of ANSD was made by confirming the presence of otoacoustic emissions, together with the absence of auditory brainstem response and absent acoustic reflexes.


Assuntos
Perda Auditiva Central/induzido quimicamente , Malária/tratamento farmacológico , Quinina/efeitos adversos , Adolescente , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Perda Auditiva Central/fisiopatologia , Humanos , Emissões Otoacústicas Espontâneas/fisiologia , Ototoxicidade
6.
Braz. j. otorhinolaryngol. (Impr.) ; 86(2): 209-216, March-Apr. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132583

RESUMO

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.


Assuntos
Humanos , Masculino , Feminino , Criança , Vias Auditivas/fisiologia , Percepção da Fala/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Dislexia/fisiopatologia , Vias Eferentes/fisiologia , Estimulação Acústica , Estudos de Casos e Controles , Ruído
7.
Mil Med ; 185(Suppl 1): 248-255, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-32074377

RESUMO

INTRODUCTION: The peripheral auditory system and various structures within the central auditory system are vulnerable to blast injuries, and even blast overpressure is at relatively mild traumatic brain injury (TBI) level. However, the extent of hearing loss in relation to blast number and time course of post-blast is not well understood. This study reports the progressive hearing damage measured in chinchillas after multiple blast exposures at mild TBI levels (103-138 kPa or 15-20 psi). MATERIALS AND METHODS: Sixteen animals (two controls) were exposed to two blasts and three blasts, respectively, in two groups with both ears plugged with foam earplugs to prevent the eardrum from rupturing. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were measured in pre- and post-blasts. Immunohistochemical study of chinchilla brains were performed at the end of experiment. RESULTS: Results show that the ABR threshold and DPOAE level shifts in 2-blast animals were recovered after 7 days. In 3-blast animals, the ABR and DPOAE shifts remained at 26 and 23 dB, respectively after 14 days. Variation of auditory cortex damage between 2-blast and 3-blast was also observed in immunofluorescence images. CONCLUSIONS: This study demonstrates that the number of blasts causing mild TBI critically affects hearing damage.


Assuntos
Traumatismos por Explosões/complicações , Perda Auditiva Provocada por Ruído/etiologia , Perda Auditiva/etiologia , Animais , Traumatismos por Explosões/fisiopatologia , Concussão Encefálica/etiologia , Concussão Encefálica/fisiopatologia , Chinchila/lesões , Chinchila/fisiologia , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Perda Auditiva/fisiopatologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Emissões Otoacústicas Espontâneas/fisiologia , Pressão/efeitos adversos , Membrana Timpânica/lesões , Membrana Timpânica/fisiopatologia
8.
Arch Sex Behav ; 49(2): 455-465, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32056039

RESUMO

Click-evoked otoacoustic emissions (CEOAEs) are echo-like sounds, generated by the inner ear in response to click-stimuli. A sex difference in emission strength is observed in neonates and adults, with weaker CEOAE amplitudes in males. These differences are assumed to originate from testosterone influences during prenatal male sexual differentiation and to remain stable throughout life. However, recent studies suggested activational, postnatal effects of sex hormones on CEOAEs. Adolescents diagnosed with gender dysphoria (GD) may receive gonadotropin-releasing hormone analogs (GnRHa) in order to suppress endogenous sex hormones and, therefore, pubertal maturation, followed by cross-sex hormone (CSH) treatment. Using a cross-sectional design, we examined whether hormonal interventions in adolescents diagnosed with GD (62 trans boys, assigned female at birth, self-identifying as male; 43 trans girls, assigned male at birth, self-identifying as female), affected their CEOAEs compared to age- and sex-matched controls (44 boys, 37 girls). Sex-typical differences in CEOAE amplitude were observed among cisgender controls and treatment-naïve trans boys but not in other groups with GD. Treatment-naïve trans girls tended to have more female-typical CEOAEs, suggesting hypomasculinized early sexual differentiation, in support of a prominent hypothesis on the etiology of GD. In line with the predicted suppressive effects of androgens, trans boys receiving CSH treatment, i.e., testosterone plus GnRHa, showed significantly weaker right-ear CEOAEs compared with control girls. A similar trend was seen in trans boys treated with GnRHa only. Unexpectedly, trans girls showed CEOAE masculinization with addition of estradiol. Our findings show that CEOAEs may not be used as an unequivocal measure of prenatal androgen exposure as they can be modulated postnatally by sex hormones, in the form of hormonal treatment.


Assuntos
Disforia de Gênero/sangue , Disforia de Gênero/fisiopatologia , Emissões Otoacústicas Espontâneas/fisiologia , Diferenciação Sexual/fisiologia , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino
9.
Synapse ; 74(1): e22128, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31403743

RESUMO

The auditory system has an extensive efferent innervation, which contributes to processes of control and regulation of the afferent input. The expression of receptors to various neurotransmitters and neuropeptides in the inner ear has been described, among which endogenous opioid receptors are found. The role of opioid receptors in the cochlea is not yet fully defined, it has been reported that opioid agonists and antagonists modulate the response to auditory stimuli and in clinical practice, multiple cases have been reported in which the consumption of opioid derivatives induce sensorineural hearing loss. In this work, we evaluated the effects of acute treatment with morphine, fentanyl, tramadol, and naloxone, in the auditory brain stem potentials (ABR), the compound action potential (CAP), and distortion products otacoustic emissions (DPOAE), across a wide range of stimulus frequencies and amplitudes. Adult Long-Evans rats of the strain CII/ZV weighing 180-220 g were used. For the ABR recording drugs were administered intraperitoneally or intravenously. For the CAP and DPOAE drugs were applied by direct perfusion in the middle ear. The opioid agonists produced a consistent increase in the amplitude of the PI component of the ABR and of the N1-P1 amplitude of the CAP. Naloxone produced no significant changes in the ABR and a reduction of the CAP N1-P1 amplitude. Also, opioid agonists induced a decrease in the amplitude of the DPOAE. These results show that the opioid receptor activation modulates both the afferent response at both the afferent response to acoustic stimuli, and also at the cochlear mechanics as revealed by DPOAE changes. These results present a significant step in understanding how opioid modulation of auditory responses may contribute to the auditory processing and to sensorineural hearing loss produced by opioids.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Analgésicos Opioides/farmacologia , Cóclea/efeitos dos fármacos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Antagonistas de Entorpecentes/farmacologia , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Cóclea/fisiologia , Fentanila/farmacologia , Morfina/farmacologia , Naloxona/farmacologia , Emissões Otoacústicas Espontâneas/fisiologia , Ratos , Ratos Long-Evans , Tramadol/farmacologia
10.
Braz J Otorhinolaryngol ; 86(2): 209-216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30772249

RESUMO

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.


Assuntos
Vias Auditivas/fisiologia , Dislexia/fisiopatologia , Vias Eferentes/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Ruído
11.
Medicine (Baltimore) ; 98(50): e18253, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852093

RESUMO

RATIONALE: Molecular mechanism underlying the autosomal recessive non-syndromic hearing loss (ARNSHL) is still plausible. Pathogenic mutations of the gap junction beta 2 protein (GJB2) are reported to be the primary causes of ARNSHL. PATIENT CONCERNS: A propositus was diagnosed as ARNSHL with bilateral congenital profound hearing loss. DIAGNOSIS: With microarray and target gene sequencing testing methods, a novel GJB2 mutant was found to be associated with ARNSHL in this Han Chinese family. INTERVENTIONS/OUTCOMES: Based on the finding in this research, prenatal screening of GJB2 mutation and genetic counseling are recommended to this family for their next pregnancy. Our interventions allow the family to plan informatively. LESSONS: In this family, we discovered 2 heterozygous carriers of c.113T>C variation in the GJB2 gene. The propositus, who had profound hearing loss, had inherited the c.113T>C variation from his normal mother and the c.235delC from his father.


Assuntos
Conexinas/genética , DNA/genética , Surdez/genética , Grupos Étnicos , Mutação , Adulto , China/epidemiologia , Conexinas/metabolismo , Análise Mutacional de DNA , Surdez/diagnóstico , Surdez/etnologia , Feminino , Humanos , Lactente , Masculino , Emissões Otoacústicas Espontâneas/fisiologia , Linhagem , Prevalência
12.
Trends Hear ; 23: 2331216519889226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31789131

RESUMO

Several types of otoacoustic emissions have been characterized in newborns to study the maturational status of the cochlea at birth and to develop effective tests of hearing. The stimulus-frequency otoacoustic emission (SFOAE), a reflection-type emission elicited with a single low-level pure tone, is the least studied of these emissions and has not been comprehensively characterized in human newborns. The SFOAE has been linked to cochlear tuning and is sensitive to disruptions in cochlear gain (i.e., hearing loss) in adult subjects. In this study, we characterize SFOAEs evoked with rapidly sweeping tones in human neonates and consider the implications of our findings for human cochlear maturation. SFOAEs were measured in 29 term newborns within 72 hr of birth using swept tones presented at 2 oct/s across a four-octave frequency range (0.5­8 kHz); 20 normal-hearing young adults served as a control group. The prevalence of SFOAEs in newborns was as high as 90% (depending on how response "presence" was defined). Evidence of probe-tip leakage and abnormal ear-canal energy reflectance was observed in those ears with absent or unmeasurable SFOAEs. Results in the group of newborns with present stimulus-frequency emissions indicate that neonatal swept-tone SFOAEs are adult-like in morphology but have slightly higher amplitude compared with adults and longer SFOAE group delays. The origin of these nonadult-like features is probably mixed, including contributions from both conductive (ear canal and middle ear) and cochlear immaturities.


Assuntos
Estimulação Acústica , Testes Auditivos/métodos , Emissões Otoacústicas Espontâneas/fisiologia , Cóclea/fisiologia , Surdez/fisiopatologia , Meato Acústico Externo , Orelha Média , Feminino , Perda Auditiva/fisiopatologia , Humanos , Recém-Nascido , Masculino , Adulto Jovem
13.
J Speech Lang Hear Res ; 62(12): 4564-4577, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31770043

RESUMO

Purpose Alterations in primary auditory functioning have been reported in patients with Parkinson's disease (PD). Despite the current findings, the pathophysiological mechanisms underlying these alterations remain unclear, and the effect of dopaminergic medication on auditory functioning in PD has been explored insufficiently. Therefore, this study aimed to systematically investigate primary auditory functioning in patients with PD by using both subjective and objective audiological measurements. Method In this case-control study, 25 patients with PD and 25 age-, gender-, and education-matched healthy controls underwent an audiological test battery consisting of tonal audiometry, short increment sensitivity index, otoacoustic emissions (OAEs), and speech audiometry. Patients with PD were tested in the on- and off-medication states. Results Increased OAE amplitudes were found when patients with PD were tested without dopaminergic medication. In addition, speech audiometry in silence and multitalker babble noise demonstrated higher phoneme scores for patients with PD in the off-medication condition. The results showed no differences in auditory functioning between patients with PD in the on-medication condition and healthy controls. No effect of disease stage or motor score was evident. Conclusions This study provides evidence for a top-down involvement in auditory processing in PD at both central and peripheral levels. Most important, the increase in OAE amplitude in the off-medication condition in PD is hypothesized to be linked to a dysfunction of the olivocochlear efferent system, which is known to have an inhibitory effect on outer hair cell functioning. Future studies may clarify whether OAEs may facilitate an early diagnosis of PD.


Assuntos
Audiometria da Fala/métodos , Transtornos da Percepção Auditiva/diagnóstico , Emissões Otoacústicas Espontâneas/fisiologia , Doença de Parkinson/fisiopatologia , Idoso , Transtornos da Percepção Auditiva/etiologia , Limiar Auditivo/fisiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Olivar/fisiopatologia , Doença de Parkinson/complicações , Sensibilidade e Especificidade
14.
Sci Rep ; 9(1): 14131, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575950

RESUMO

People with normal hearing thresholds can nonetheless have difficulty with understanding speech in noisy backgrounds. The origins of such supra-threshold hearing deficits remain largely unclear. Previously we showed that the auditory brainstem response to running speech is modulated by selective attention, evidencing a subcortical mechanism that contributes to speech-in-noise comprehension. We observed, however, significant variation in the magnitude of the brainstem's attentional modulation between the different volunteers. Here we show that this variability relates to the ability of the subjects to understand speech in background noise. In particular, we assessed 43 young human volunteers with normal hearing thresholds for their speech-in-noise comprehension. We also recorded their auditory brainstem responses to running speech when selectively attending to one of two competing voices. To control for potential peripheral hearing deficits, and in particular for cochlear synaptopathy, we further assessed noise exposure, the temporal sensitivity threshold, the middle-ear muscle reflex, and the auditory-brainstem response to clicks in various levels of background noise. These tests did not show evidence for cochlear synaptopathy amongst the volunteers. Furthermore, we found that only the attentional modulation of the brainstem response to speech was significantly related to speech-in-noise comprehension. Our results therefore evidence an impact of top-down modulation of brainstem activity on the variability in speech-in-noise comprehension amongst the subjects.


Assuntos
Atenção/fisiologia , Limiar Auditivo/fisiologia , Tronco Encefálico/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Audição/fisiologia , Fala/fisiologia , Estimulação Acústica/métodos , Adulto , Audiometria da Fala/métodos , Cóclea/fisiologia , Feminino , Perda Auditiva Provocada por Ruído/fisiopatologia , Testes Auditivos/métodos , Humanos , Individualidade , Masculino , Ruído , Emissões Otoacústicas Espontâneas/fisiologia , Percepção da Fala/fisiologia , Adulto Jovem
15.
Trends Hear ; 23: 2331216519870942, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31558110

RESUMO

The medial olivocochlear reflex (MOCR) has been implicated in several auditory processes. The putative role of the MOCR in improving speech perception in noise is particularly relevant for children who complain of listening difficulties (LiD). The hypothesis that the MOCR may be impaired in individuals with LiD or auditory processing disorder has led to several investigations but without consensus. In two related studies, we compared the MOCR functioning of children with LiD and typically developing (TD) children in the same age range (7-17 years). In Study 1, we investigated ipsilateral, contralateral, and bilateral MOCR using forward-masked click-evoked otoacoustic emissions (CEOAEs; n = 17 TD, 17 LiD). In Study 2, we employed three OAE types: CEOAEs (n = 16 TD, 21 LiD), stimulus frequency OAEs (n = 21 TD, 30 LiD), and distortion product OAEs (n = 17 TD, 22 LiD) in a contralateral noise paradigm. Results from both studies suggest that the MOCR functioning is not significantly different between the two groups. Some likely reasons for differences in findings among published studies could stem from the lack of strict data quality measures (e.g., high signal-to-noise ratio, control for the middle ear muscle reflex) that were enforced in the present study. The inherent variability of the MOCR, the subpar reliability of current MOCR methods, and the heterogeneity in auditory processing deficits that underlie auditory processing disorder make detecting clinically relevant differences in MOCR function impractical using current methods.


Assuntos
Percepção Auditiva/fisiologia , Cóclea/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Estimulação Acústica , Adolescente , Criança , Feminino , Humanos , Masculino , Ruído , Reflexo/fisiologia , Reprodutibilidade dos Testes , Percepção da Fala
16.
Trop Med Int Health ; 24(11): 1264-1276, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31495037

RESUMO

OBJECTIVES: To describe the occurrence of both peripheral and central auditory system dysfunction in sickle cell anaemia (SCA) patients and discuss the different mechanisms hypothesised to be responsible for these alterations. METHODS: An electronic search was conducted using PubMed Central® (MEDLINE), LILACS® and Scopus® databases. This systematic review was performed in accordance with the PRISMA statement. Original observational studies that utilised audiological tests for auditory system evaluations in SCA were included. RESULTS: A total of 183 records were found in the databases searched. Twenty-one of these studies met the inclusion criteria. Pooled prevalence of sensorineural hearing loss (SNHL) was 20.5% (CI: 10.3-33%). Retrocochlear involvement was detected with the auditory brainstem response, which assesses integrity of the cochlea, 8th cranial nerve and brainstem structures. In addition, the increase in otoacoustic emission amplitudes in SCA patients indicates changes in cochlear micromechanics and precedes the expression of a detectable cochlear pathology. CONCLUSION: The prevalence of the SNHL is higher than in the general population. Dysfunction of the auditory system may be present in SCA patients, with the most probable mechanism being the presence of circulatory disturbances resulting from the chronic inflammatory state of the disease.


Assuntos
Anemia Falciforme/epidemiologia , Perda Auditiva Neurossensorial/epidemiologia , Adolescente , Criança , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Humanos , Masculino , Emissões Otoacústicas Espontâneas/fisiologia , Doenças Retrococleares/epidemiologia
17.
Purinergic Signal ; 15(3): 343-355, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31377959

RESUMO

A major component of slowly reversible hearing loss which develops with sustained exposure to noise has been attributed to release of ATP in the cochlea activating P2X2 receptor (P2X2R) type ATP-gated ion channels. This purinergic humoral adaptation is thought to enable the highly sensitive hearing organ to maintain function with loud sound, protecting the ear from acoustic overstimulation. In the study that established this hearing adaptation mechanism as reported by Housley et al. (Proc Natl Acad Sci U S A 110:7494-7499, 2013), the activation kinetics were determined in mice from auditory brainstem response (ABR) threshold shifts with sustained noise presentation at time points beyond 10 min. The present study was designed to achieve finer resolution of the onset kinetics of purinergic hearing adaptation, and included the use of cubic (2f1-f2) distortion product otoacoustic emissions (DPOAEs) to probe whether the active mechanical outer hair cell 'cochlear amplifier' contributed to this process. We show that the ABR and DPOAE threshold shifts were largely complete within the first 7.5 min of moderate broadband noise (85 dB SPL) in wildtype C57Bl/6J mice. The ABR and DPOAE adaptation rates were both best fitted by a single exponential function with ~ 3 min time constants. ABR and DPOAE threshold shifts with this noise were minimal in mice null for the P2rx2 gene encoding the P2X2R. The findings demonstrate a considerably faster purinergic hearing adaptation to noise than previously appreciated. Moreover, they strongly implicate the outer hair cell as the site of action, as the DPOAEs stem from active cochlear electromotility.


Assuntos
Adaptação Fisiológica/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Células Ciliadas Auditivas Externas/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Estimulação Acústica , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ruído
18.
Int Tinnitus J ; 23(1): 17-25, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469523

RESUMO

INTRODUCTION: Tinnitus is defined as the perception of sound that results completely from activity within the nervous system without any corresponding mechanical, vibratory activity within the cochlea, and not related to external stimulation of any kind. It disrupts the daily life of 1 out of every 200 adults. The source of tinnitus generation is not limited to the peripheral auditory system. However, there are abnormalities seen in BERA in tinnitus patients depicting auditory pathway involvement. Oto-acoustic emissions are mechanical vibrations generated in the cochlea, which are evaluated by TEOAE and DPOAE whereas BERA evaluates both cochlea and brainstem auditory pathway for any conduction abnormalities. The aim of the study is to analyze the changes in OAE and BERA in patients suffering from tinnitus with normal hearing, which may help us to understand the patho-physiology of tinnitus. METHODS: This is a prospective study conducted in a tertiary care hospital in Northern India between 1st December 2015 to 31st July 2017. All patients of tinnitus with normal hearing were included in the study group, whereas Individuals with normal hearing with no other ear complaints were included in control group. Total 160 Ears were evaluated with 80 ears in both study and control group each. Patients with PTA >25dB, age >55 years or any chronic medical illness were excluded from the study. RESULTS: 80 individuals (46 Males and 34 Females) were divided into study and control Group (80 Ears each). Tinnitus was bilateral in 28 subjects (53.84%) and unilateral in 24 subjects (46.16%). Both control and study group showed significant difference in TEOAE and DPOAE study. In TEOAE, 8 (10%) ears in control group and 30 ears (37.5%) in study group showed test result as REFER whereas in DPOAE 10 (12.5%) ears in control group and 35 (43.8%) ears showed test result as REFER. All these result were statistically significant. In BERA the latency of wave I was significantly prolonged in study group as compared to control group, while difference between all other parameters between the two groups was insignificant. CONCLUSIONS: There were various significant abnormalities seen in parameters of Oto-Acoustic Emissions (OAE) and Brainstem Evoked Response Audiometry (BERA). So these tests should be included in the test battery for the screening of patients complaining of tinnitus even with normal hearing.


Assuntos
Audiometria de Resposta Evocada/métodos , Audiometria de Tons Puros/métodos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Zumbido/diagnóstico , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Centros de Atenção Terciária
19.
Int Tinnitus J ; 23(1): 31-36, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469525

RESUMO

Children hospitalized in Neonatal Intensive Care Units (NICU) present an increased risk for Sensorineural Hearing Loss (SNHL) due to prematurity, hypoxia-ischemia, hyperventilation, low birth weight and the use of ototoxic drugs. The aim of this study was to assess the prevalence of SNHL in newborns hospitalized in a NICU using Transient Evoked Otoacoustic Emissions (TEOAE) and Automated Auditory Brainstem Responses (A-ABR) and analyze the associated risk factors. A sample of 153 newborns hospitalized in NICU underwent TEOAE, A-ABR and clinical ABR to evaluate the presence of hearing deficits. Prevalence of SNHL was calculated and odds ratio for specific risk factors was measured. One-hundred fifteen babies (86.7%) presented normal hearing at TEOAE and A-ABR. Fifteen children had a REFER response at TEOAE and a PASS response at A-ABR. Twenty-five children (16.3%) had a REFER A-ABR and were addressed to clinical ABR. A diagnosis of SNHL was made in 12 (7.8%) newborns. An increased risk of SNHL was observed in preterm children <28 weeks (p=0.0135), in children with neurological disorders (p=0.02), that underwent surgery (p=0.0002), affected from premature retinopathy (p=0.0006), craniofacial malformation (p=0.007) and that had sepsis (p=0.04). Additional risk factors for SNHL in our sample were a maternal disease during pregnancy (p=0.0011), cesarean delivery (p<0.0001) and a twin pregnancy (p<0.0001). SNHL in newborns is correlated with hospitalization in NICU. An accurate hearing screening associated to a rigorous clinical medical collection of data is necessary to promptly identify cases of SNHL in children with a special attention to those hospitalized in NICU and plan proper intervention.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Perda Auditiva Neurossensorial/congênito , Perda Auditiva Neurossensorial/diagnóstico , Recém-Nascido Prematuro , Triagem Neonatal/métodos , Emissões Otoacústicas Espontâneas/fisiologia , Feminino , Seguimentos , Testes Auditivos/métodos , Humanos , Recém-Nascido , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/epidemiologia , Unidades de Terapia Intensiva Neonatal , Masculino , Prevalência , Medição de Risco , Índice de Gravidade de Doença
20.
Otol Neurotol ; 40(9): 1246-1252, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31469797

RESUMO

HYPOTHESIS: The characteristics of auditory brainstem response (ABR), electrocochleogram (ECochG), and distortion product otoacoustic emissions (DPOAE) of different degrees of selective outer hair cells (OHCs) loss may be helpful for clinicians to evaluate the pathogeny, diagnosis, and rehabilitation of individuals' hearing loss. BACKGROUND: How many OHCs are necessary to maintain cochlear amplifier function remains unknown. The electrophysiologic characteristics may indicate different degrees of OHCs loss. METHODS: Electrophysiological characteristics were tested using 8-kHz pure-tone stimulus and OHCs counted specifically in the region of the cochlea corresponding to 8-kHz. Rat models of selective OHCs loss were established by injecting kanamycin (KM) at various dosages, and the region of 8-kHz was obtained by 8-kHz pure-tone exposure. RESULTS: The ABR thresholds were affected slightly with OHCs loss < 30%, and were increased dramatically with OHCs loss ranging from 30 to 70%, but the thresholds did not increase further when OHCs loss exceeded 70%. As OHCs loss increased, the compound action potential (CAP) amplitude decreased. The CAP amplitude and OHCs loss were negatively correlated. Moreover, the summating potential (SP)/action potential (AP) increased as OHCs loss increased. DPOAE and cochlear microphonics (CM) exhibited reduced amplitudes when OHCs loss < 30%. CONCLUSIONS: Electrophysiologic characteristics may indicate different degrees of OHCs loss. While OHCs loss > 70%, the cochlear amplification may lose completely, but it is difficult to detect OHCs loss < 30%, because the ABR or DPOAE may reveal "normal" at this level. Moreover, the decreased CAP amplitude or increased SP/AP may be indicators for OHCs loss.


Assuntos
Células Ciliadas Auditivas Externas/patologia , Perda Auditiva Neurossensorial/patologia , Perda Auditiva Neurossensorial/fisiopatologia , Emissões Otoacústicas Espontâneas/fisiologia , Animais , Audiometria de Resposta Evocada , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
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