Milaine Dominici Sanfins

Speech auditory brainstem response (speech ABR) in the differential diagnosis of scholastic difficulties.

Learning spoken and written language depends on the assimilation of acoustic elements and the representation of phonetic characteristics of a language. Auditory processing, phonological awareness, and auditory discrimination are factors that affect the learning of reading and writing, because they are directly related to receptive hearing. Researchers have associated the presence of learning disabilities with hearing deficits in children. After an acoustic stimulation, electrophysiological evaluation of hearing can establish an anatomical and functional correlation in the central auditory nervous system that occurs through the activation of several structures throughout the system. Thus, in cases of learning disabilities, an

A REVIEW OF THE CLINICAL APPLICABILITY OF SPEECH-EVOKED AUDITORY BRAINSTEM RESPONSES

Through a systematic literature review, this paper evaluates the clinical applicability of speech-evoked auditory brainstem responses (ABRs). The survey was done on five databases, with the following key words: speech ABR; ABR-speech; speech auditory brainstem response; auditory evoked potential to speech; speech-evoked brainstem response; complex sounds; and cABR. The search generated a list of 1288 items published between 2005 and 2015. After applying pre-established criteria of inclusion and exclusion, 21 publications remained. The collected data show that: (i) research on speech ABR has been done on diverse age groups, although teenagers and adolescents have been less studied; (ii) the speech ABR procedure has been shown to be a reliable and effective tool in evaluating the coding of speech sounds in the brainstem, and can also be applied to young children; and (iii) speech ABR has been shown to be effective in the differential diagnosis of diseases with similar features and symptoms.

Contralateral Noise Stimulation Delays P300 Latency in School-Aged Children

Background and Objective The auditory cortex modulates auditory afferents through the olivocochlear system, which innervates the outer hair cells and the afferent neurons under the inner hair cells in the cochlea. Most of the studies that investigated the efferent activity in humans focused on evaluating the suppression of the otoacoustic emissions by stimulating the contralateral ear with noise, which assesses the activation of the medial olivocochlear bundle. The neurophysiology and the mechanisms involving efferent activity on higher regions of the auditory pathway, however, are still unknown. Also, the lack of studies investigating the effects of noise on human auditory cortex, especially in peadiatric population, points to the need for recording the late auditory potentials in noise conditions. Assessing the auditory efferents in schoolaged children is highly important due to some of its attributed functions such as selective attention and signal detection in noise, which are important abilities related to the development of language and academic skills. For this reason, the aim of the present study was to evaluate the effects of noise on P300 responses of children with normal hearing. Methods P300 was recorded in 27 children aged from 8 to 14 years with normal hearing in two conditions: with and whitout contralateral white noise stimulation. Results P300 latencies were significantly longer at the presence of contralateral noise. No significant changes were observed for the amplitude values. Conclusion Contralateral white noise stimulation delayed P300 latency in a group of school-aged children with normal hearing. These results suggest a possible influence of the medial olivocochlear activation on P300 responses under noise condition.

An Analysis of The Parameters Used In Speech ABR Assessment Protocols

The aim of this study was to assess the parameters of choice, such as duration, intensity, rate, polarity, number of sweeps, window length, stimulated ear, fundamental frequency, first formant, and second formant, from previously published speech ABR studies. To identify candidate articles, five databases were assessed using the following keyword descriptors: speech ABR, ABR-speech, speech auditory brainstem response, auditory evoked potential to speech, speech-evoked brainstem response, and complex sounds. The search identified 1288 articles published between 2005 and 2015. After filtering the total number of papers according to the inclusion and exclusion criteria, 21 studies were selected. Analyzing the protocol details used in 21 studies suggested that there is no consensus to date on a speech-ABR protocol and that the parameters of analysis used are quite variable between studies. This inhibits the wider generalization and extrapolation of data across languages and studies.

Estudo das Emissões Otoacústicas Transientes em Crianças e Adolescentes Submetidos à Miringotomia

Introdução O Teste de Emissões Otoacústicas por transientes (EOAT) avalia o estado funcional da cóclea, mais especificamente das células ciliadas externas. Pode sofrer influência das condições funcionais das orelhas externa e/ou média. Este procedimento é altamente sensível a mudanças cocleares e pequenas disfunções de orelha média podem prejudicar a detecção adequada das emissões1 , A otite média (OM) é definida como uma inflamação da orelha média frequentemente associada a um aumento de fluído infectado ou não2. A sua repetição pode causar alterações nas estruturas periféricas do sistema auditivo. Assim, danos irreversíveis à orelha média ou à cóclea podem advir dessa afecção na orelha média 3,4 . O objetivo geral deste estudo foi de analisar os resultados da avaliação das EOAT em indivíduos com histórico de otite média secretora (OMS) que foram submetidos à miringotomia com colocação de tubo de ventilação (MTV) bilateralmente.

Speech-Evoked Brainstem Response

The auditory brainstem response (ABR) is a clinical tool to assess the neural functionality of the auditory brainstem. The use of verbal stimuli in ABR protocols has provided important information of how the speech stimuli are processed by the brainstem structure. The perception of speech sounds seems to begin in the brainstem, which has an important role in the reading process and the phonological acquisition speech ABR assessment allows the identification of fine-grained auditory processing deficits, which do not appear in click evoked ABR responses. The syllable /da/ is commonly used by speech ABR assessment due to it being considered a universal syllable and allows it to be applied in different countries with good clinical assertiveness. The speech ABR is a objective, fast procedure that can be applied to very young subjects. It be utilized in different languages and can provide differential diagnoses of diseases with similar symptoms, as an effective biomarker of auditory processing disorders present in various diseases, such as dyslexia, specific language impairment, hearing loss, auditory processing disorders, otitis media, and scholastic difficulties. Speech ABR protocols can assist in the detection, treatment, and monitoring of various types of hearing impairments.

WIDEBAND IMMITTANCE IN NEONATES: A SYSTEMATIC LITERATURE REVIEW

Objective: To analyze the literature on wideband immittance testing and to evaluate the success of these procedures in evaluating middle ear function in newborns. Methods: A systematic literature review was conducted using as keywords: wideband, tympanometry, reflectance, absorbance, immittance. Papers which did not address neonates were excluded from the review. From each article specific information was extracted referring to the following: sample size, population characteristics, equipment, stimulus type, study evaluation, and study conclusion. Conclusions: This systematic review considers that wideband immittance is a promising way for evaluating middle ear function in neonates. It is necessary to establish regulatory standards for different age groups of neonates and infants.

Achados audiológicos e comportamentais em crianças submetidas à miringoplastia bilateral – um estudo comparativo

Purpose: to analyze pre-surgical hearing evaluation in children who suffering from secretory otitis media in their first five years of age. Also to verify the length of time tubes have remained in the eardrum and analyze the test results of auditory processing after myringotomy surgery. Method: 79 students between eight and 12 years old were divided into two groups: 1 - 40 students without otitis media history and 2 - 39 students suffering from secretory otitis media in their first five years of age and who have undergone a myringotomy surgery. The individuals underwent complete audiological evaluation and assessment of Auditory Processing. Results: all patients showed conductive hearing loss in the pre-operative audiologic tests. The mean time of ventilation tubes was 11,8 months. The left ear showed significant lower performance in the dichotic digits and pitch pattern sequence tests. The students from group 2 showed lower performance whether compared to group 1 in the dichotic digits test and gaps-in-noise. Conclusion: children with a history of otitis media in the early years of life showed the conductive hearing loss responses in the pre-surgical evaluation and lower responses in dichotic test of digits and gaps-in-noise.

Speech-evoked brainstem response in normal adolescent and children speakers of Brazilian Portuguese

This study aimed to analyze the coding responses of speech sounds (syllable/da/) in children and adolescent speakers of Brazilian Portuguese with typical development and normal hearing, aged between 8 and 16 years, in order to establish normative data of speech ABR response. This normative data can be used as a reference for speech ABR responses and also to enable the diagnosis in individuals with different pathologies. The analyze for absolute latency of speech sounds, more specifically the syllable/da/, for speech-ABR in children and adolescent speakers of Brazilian Portuguese with typical development were: right ear - wave V (6,43-6,57), wave A (7,35-7,57), wave C (18,19-18,46), wave D (21,99-22,42), wave E (30,73-31,05), wave F (39,19-39,55) and wave O (47,75-48,24) and left ear - wave V (6,44-6,57), wave A (7,36-7,59), wave C (18,26-18,55), wave D (22,22 -22,50), wave E (30,58-30,97), wave F (39,05-39,35) and wave O (47,78-48,13). For the amplitude values (μv), the responses were within the following ranges: right ear - wave V (0,10-0,14), wave A (0,19-0,25), wave C (0,08-0,13), wave D (0,11-0,17), wave E (0,17-0,42), wave F (0,14-0,33) and wave O (0,11-0,31) and left ear - wave V (0,09-0,13), wave A (0,08-0,23), wave C (0,08-0,14), wave D (0,10-0,15), wave E (0,20-0,26), wave F (0,16-0,22) and wave O (0,12-0,20). For the values of complex VA (slope: μv/ms and area μv x ms) the follow values obtained were: right ear - slope (0,32-0,42) and area (0,29-0,38) and left ear - slope (0,30-0,39) and area (0,27-0,35).

Suppression of the Cognitive Auditory Evoked Potential P300 in School-Age Children with Normal Hearing

Introduction: Auditory processing depends on afferent and efferent auditory pathways integrity. Most of the studies designed to investigate the efferent system focused on the suppression of the otoacoustic emissions. However, the neural mechanisms underlying efferent activity on higher regions, such as thalamus and cortex, are still not well known. Objectives: To analyze the suppression effect of the cognitive auditory evoked potential in children with normal hearing. Methods: Eighteen children aged 8 to 13 years participated in the study. All the participants had pure-tone threshold below 20 dBHL for octaves from 250 to 8,000 Hz, “A”-type tympanogram with the presence of ipsilateral and contralateral acoustic reflexes, functional integrity of auditory pathways assessed by ABR, and no neurological disorders. P300 was recorded at 70 dBHL. The stimulus presented was tone burst at the frequency of 2 kHz for the infrequent stimulus and 1 kHz for the frequent one. The equipment used was a Biologic Navigator Pro and the test was repeated using contralateral white noise stimulus of 70 dBHL. Results: The studied children showed significantly longer P300 latencies at the presence of white noise contralateral stimulation. Amplitude mean values reduced with white noise, but there was no statistical significance. Conclusion: These results suggest a possible influence of the auditory efferent system over the P300 responses when contralateral white noise stimulation is used, causing longer wave latencies. New studies should be conducted for a better understanding of these results and for improving the use of this procedure in clinical researches. Keywords: hearing, auditory evoked potentials, electrophysiology.