The P300 Auditory Evoked Potential in Cochlear Implant Users: A Scoping Review

Abstract Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.

The P300 Auditory Evoked Potential in Cochlear Implant Users: A Scoping Review.

Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.

The Effects of Monaural Stimulation on Frequency-Following Responses in Adults Who Can Sing in Tune and Those Who Cannot

Abstract Introduction Musicians have an advantage over non-musicians in detecting, perceiving, and processing nonverbal (i.e., environmental sounds, tones and others) and verbal sounds (i.e., consonant, vowel, phrases and others) as well as instrumental sounds. In contrast to the high skill of musicians, there is another group of people who are tone-deaf and have difficulty in distinguishing musical sounds or singing in tune. These sounds can originate in different ways, such as a musical instrument, orchestra, or the human voice. Objectives The objective of the present work is to study frequency-following responses (FFRs) in individuals who can sing in-tune and those who sing off-tune. Methods Electrophysiological responses were recorded in 37 individuals divided in two groups: (i) control group (CG) with professional musicians, and (ii) experimental group (EG) with non-musicians. Results There was homogeneity between the two groups regarding age and gender. The CG had more homogeneous responses in the latency of the FFRs waves when responses between the right and left ears were compared to those of the EG. Conclusions This study showed that monaural stimulation (right or left) in an FFR test is useful for demonstrating impairment of speech perception in individuals who sing off tune. The response of the left ear appears to present more subtlety and reliability when identifying the coding of speech sound in individuals who sing off tune.

The Effects of Monaural Stimulation on Frequency-Following Responses in Adults Who Can Sing in Tune and Those Who Cannot.

Introduction Musicians have an advantage over non-musicians in detecting, perceiving, and processing nonverbal (i.e., environmental sounds, tones and others) and verbal sounds (i.e., consonant, vowel, phrases and others) as well as instrumental sounds. In contrast to the high skill of musicians, there is another group of people who are tone-deaf and have difficulty in distinguishing musical sounds or singing in tune. These sounds can originate in different ways, such as a musical instrument, orchestra, or the human voice. Objective The objective of the present work is to study frequency-following responses (FFRs) in individuals who can sing in-tune and those who sing off-tune. Methods Electrophysiological responses were recorded in 37 individuals divided in two groups: (i) control group (CG) with professional musicians, and (ii) experimental group (EG) with non-musicians. Results There was homogeneity between the two groups regarding age and gender. The CG had more homogeneous responses in the latency of the FFRs waves when responses between the right and left ears were compared to those of the EG. Conclusion This study showed that monaural stimulation (right or left) in an FFR test is useful for demonstrating impairment of speech perception in individuals who sing off tune. The response of the left ear appears to present more subtlety and reliability when identifying the coding of speech sound in individuals who sing off tune.

Electrophysiological and Behavioral Evaluation of Auditory Processing in Adults with Dysphonia.

Introduction Dysphonia is an oral communication disorder. The voice and hearing are interrelated aspects. Hearing is an important sensory input for monitoring the vocal pattern. The relation between hearing abilities and dysphonia represents a contribution both in scientific and in clinical terms, especially in cases in which satisfactory results are not achieved in the therapeutic process. Objective To characterize long-latency auditory evoked potential (P300) with tonal and complex stimuli, and to make a behavioral evaluation of auditory processing in adults with behavioral dysphonia. Method The sample used for the present study consisted of 20 subjects from both genders with ages ranging from 18 and 58, who were diagnosed with behavioral dysphonia. The evaluations occurred in a single 2-hour session, in which the procedures of clinical history, pure tone and speech audiometries, acoustic immittance measures, and behavioral and electrophysiological evaluations of auditory processing were performed. Results The descriptive measures of P3 latency elicited by tonal and complex stimuli showed similar results for the right and left ears, without statistically significant differences. In the qualitative analysis, the results observed were within the normality patterns for the P3 component for both tonal and complex stimuli. As for the behavioral evaluation of auditory processing, abnormal results were observed in 100% of the sample. Abnormalities were found in the auditory skills of ordering and temporal resolution and figure-background obtained from the duration pattern, random gap detection, and dichotic tests (syllables and words), respectively. Conclusion The evaluated patients presented central auditory processing disorder, evidenced by behavioral assessment.

Differential Cortical Pattern in Auditory Task Oddball Paradigm in Children Exposed to Alcohol during Pregnancy.

The negative effects of fetal alcohol exposure on child development are well documented. This study investigated the electrophysiological processing of cortical level acoustic signals in a group of 21 children prenatally exposed to alcohol. Participants aged 13-14 years at the time of the study were recruited from a longitudinal cohort sample. The study employed an observational, cross-sectional blind design and participants were divided into two groups: with and without fetal exposure to alcohol. Neurophysiological measures recorded N1, P2, N2, P3, P3a, and P3b components using the Oddball paradigm. Our results showed that the mothers' sociodemographic conditions at the time of birth, as well as the children's birth weights were homogeneous between the groups, though the Apgar score was lower in the exposed group (EG). The neurophysiological components that showed different results in the groups were P2 and P3a. P2 amplitude was higher in the midline central electrode (Cz) compared to the midline parietal electrode (Pz), demonstrating a group interaction for exposed children. For P3a there was an interaction of group and electrode position, and the EG showed higher amplitudes in Cz compared to the unEG. However, the Apgar score did not influence these results. In conclusion, children who had fetal exposure to alcohol presented electrophysiological recordings distinct from the control group. These differences occurred both in the P2 component - which reflects a bottom-up mechanism of auditory processing - as well as the P3a component, which may reflect the participation of supra-modal hearing mechanisms.

Cortical auditory-evoked potential as a biomarker of central auditory maturation in term and preterm infants during the first 3 months

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.

Long-term Effects of Unilateral and Bilateral Otitis Media and Myringotomy on Long-Latency Verbal and Non-Verbal Auditory-Evoked Potentials

Abstract Introduction Otitis media (OM) is considered one of the most common reasons patients seek medical care in childhood. The fluctuating nature of hearing loss in cases of OM leads to irregular sound stimulation of the central auditory nervous system. Objectives To analyze the long-latency auditory-evoked potential (LLAEP) by verbal and nonverbal sounds in children with a history of OM in the first six years of life. Methods A total of 106 schoolchildren participated in the study, 55 females and 51 males, aged between 8 and 16 years, who were divided into 3 groups: the control group (CG), the bilateral experimental group (BEG), and the unilateral experimental group (UEG). All children underwent a complete audiological evaluation (audiometry, logoaudiometry and immitance testing) and an electrophysiological evaluation (LLAEP with toneburst stimulus - LLAEP-TB, and LLAEP with speech stimulus - LLAEP-S). Results Both study groups (BEG and UEG) presented a statistically lower performance (p < 0.005) when compared with the CG regarding all of the electrophysiological tests with the prolongation of the latency values and decrease in the amplitude values: LLAEP-TB (BEG: latency - N1, P2, N2 [females] and P300, amplitude - N1 and P2), LLAEP-S (BEG: latency - P2 and N2 [females], amplitude - P2 /UEG: latency - P2 and P300, amplitude: N1 and P2). Conclusion Children who had suffered secretory OM in the first six years of life and who had undergone myringotomy for the placement of a ventilation tube, either unilaterally or bilaterally, presented worse performance in their electrophysiological responses to verbal and nonverbal LLAEPs.

Long-term Effects of Unilateral and Bilateral Otitis Media and Myringotomy on Long-Latency Verbal and Non-Verbal Auditory-Evoked Potentials.

Introduction Otitis media (OM) is considered one of the most common reasons patients seek medical care in childhood. The fluctuating nature of hearing loss in cases of OM leads to irregular sound stimulation of the central auditory nervous system. Objectives To analyze the long-latency auditory-evoked potential (LLAEP) by verbal and nonverbal sounds in children with a history of OM in the first six years of life. Methods A total of 106 schoolchildren participated in the study, 55 females and 51 males, aged between 8 and 16 years, who were divided into 3 groups: the control group (CG), the bilateral experimental group (BEG), and the unilateral experimental group (UEG). All children underwent a complete audiological evaluation (audiometry, logoaudiometry and immitance testing) and an electrophysiological evaluation (LLAEP with toneburst stimulus - LLAEP-TB, and LLAEP with speech stimulus - LLAEP-S). Results Both study groups (BEG and UEG) presented a statistically lower performance ( p < 0.005) when compared with the CG regarding all of the electrophysiological tests with the prolongation of the latency values and decrease in the amplitude values: LLAEP-TB (BEG: latency - N1, P2, N2 [females] and P300, amplitude - N1 and P2), LLAEP-S (BEG: latency - P2 and N2 [females], amplitude - P2 /UEG: latency - P2 and P300, amplitude: N1 and P2). Conclusion Children who had suffered secretory OM in the first six years of life and who had undergone myringotomy for the placement of a ventilation tube, either unilaterally or bilaterally, presented worse performance in their electrophysiological responses to verbal and nonverbal LLAEPs.

Influence of malnutrition on the development of the central nervous system of malnourished children.

Introduction: Protein-caloric malnutrition is a public health concern in certain areas of the Brazil. It can affect growth, the auditory nervous system development and, consequently, the cognition. This study compared the Brainstem Auditory Evoked Potential (BAEP) between malnourished and eutrophic children.Methods: A total of 111 children, aged 0-60 months, were examined: 57 were malnourished, according to the World Health Organization criteria, and 54 were normo-nourished. All the subjects underwent otorhinolaryngological evaluations and had acoustic immittance and transient evoked otoacoustic emissions within the normal range. The BAEP responses to click and tone burst stimuli were recorded at intensities of 80, 60, 40, and 30 dBNA.Results: We observed that latencies of I, III, and V waves and interpeaks III-V at 80 dBNA with click stimuli were significantly higher in all malnourished children when compared to those in the eutrophic children, as was the I-V interval in the 0- to 24-month group. The V-wave latencies at those intensities were also significantly higher in malnourished children.Conclusions: Malnourished children presented changes in BAEP characterized by delayed wave latency and interpeak intervals when compared to eutrophic children, suggesting alterations in both peripheral and central auditory pathways development and maturation.

Brainstem Auditory Evoked Potentials in infants aged 1 to 24 months during a hearing health care service

OBJECTIVES: Assessing infants' hearing is of utmost importance, as hearing at this phase is required for the development of oral language. Through hearing, human beings are capable of developing communication. The Brainstem Auditory Evoked Potentials are an indispensable test to diagnose deafness in infants. This study aimed to analyze the results of the Brainstem Auditory Evoked Potentials in children with risk factors for hearing loss. METHODS: This cross-sectional study analyzed the Brainstem Auditory Evoked Potentials in 123 infants aged 1 to 24 months at a hearing health care service. The Vivosonic Integrity V500 equipment, which enabled the child to be awake while the testing was carried out, was used in this study. The data were compared by gestational age and sex, according to the standards suggested in the equipment handbook. RESULTS: A significant difference was verified for age ranges 4 to 6 months, 13 to 15 months (waves I and V), and 7 to 9 months (wave V). The lower values in absolute wave latencies were comparable to data from the equipment handbook, justifying the need for standardization of the screening process. CONCLUSION: There are some differences between the standards in the equipment handbook and those observed in our study. These results will serve as a reference for the standardization of the equipment used in the hearing health care service.

Mismatch Negativity in Children: Reference Values

Abstract Introduction The Mismatch Negativity (MMN) auditory evoked potential evaluation is a promising procedure to assess objectively the ability of auditory discrimination. Objective To characterize the latency and amplitude values of MMN in children with normal auditory thresholds and without auditory complaints. Methods Children between 5 and 11 years old participated in the present study. All participants underwent acoustic immittance measurements and tonal and vocal audiometry. The MMN was recorded with the MASBE ATC Plus system (Contronic, Pelotas, RS, Brazil). The electrodes were fixed in Fz (active electrode), Fpz (ground electrode) and in M2 and M1 (references electrodes). The intensity used was 80 dBHL, the frequent stimulus was 1,000 Hz and the rare stimulus was 2,000 Hz. The stimuli were presented in both ears separately. Results For the female group, the mean latencies and amplitude of MMN were 177.3 ms and 5.01 μV in the right ear (RE) and 182.4ms and 5.39 μV in the left ear (LE). In the male group, themean latencies were 194.4 ms in the RE and 183.6ms in the LE, with an amplitude of 5.11 μV in the RE and 5.83 μV in the LE. There was no statistically significant difference between ears (p = 0.867 - latency and p = 0.178 - amplitude), age (p > 0.20) and the gender of the participants (p > 0.05). Conclusion Using the described protocol, the mean latency value of MMN was 184.0 ms for RE and 182.9 ms for LE, and the amplitude was 5.05 μV and 5.56 μV for the left and right ears, respective.

Mismatch Negativity in Children: Reference Values.

Introduction The Mismatch Negativity (MMN) auditory evoked potential evaluation is a promising procedure to assess objectively the ability of auditory discrimination. Objective To characterize the latency and amplitude values of MMN in children with normal auditory thresholds and without auditory complaints. Methods Children between 5 and 11 years old participated in the present study. All participants underwent acoustic immittance measurements and tonal and vocal audiometry. The MMN was recorded with the MASBE ATC Plus system (Contronic, Pelotas, RS, Brazil). The electrodes were fixed in Fz (active electrode), Fpz (ground electrode) and in M2 and M1 (references electrodes). The intensity used was 80 dBHL, the frequent stimulus was 1,000 Hz and the rare stimulus was 2,000 Hz. The stimuli were presented in both ears separately. Results For the female group, the mean latencies and amplitude of MMN were 177.3 ms and 5.01 µV in the right ear (RE) and 182.4 ms and 5.39 µV in the left ear (LE). In the male group, the mean latencies were 194.4 ms in the RE and 183.6 ms in the LE, with an amplitude of 5.11 µV in the RE and 5.83 µV in the LE. There was no statistically significant difference between ears ( p = 0.867 - latency and p = 0.178 - amplitude), age ( p > 0.20) and the gender of the participants ( p > 0.05). Conclusion Using the described protocol, the mean latency value of MMN was 184.0 ms for RE and 182.9 ms for LE, and the amplitude was 5.05 µV and 5.56 µV for the left and right ears, respective.

Potencial Evocado Auditivo de Tronco Encefálico com estímulos clique e Ichirp / Auditory Evoked Brain Stem Potential with click stimuli and Ichirp / Potencial Evocado Auditivo de Tronco Encefálico con estímulos clic y Ichirp

Objetivo: Analisar os traçados do Potencial Evocado Auditivo de Tronco Encefálico com o uso dos estímulos clique e o Ichirp em adultos com audição normal. Método: Trata-se de um estudo transversal, de caráter analítico, quantitativo. Foram analisados exames de Potencial Evocado Auditivo de Tronco Encefálico de 11 adultos ouvintes (2 orelhas), na faixa etária entre 20 e 25 anos, sem alterações auditivas. Esses sujeitos realizaram o registro do Potencial Evocado Auditivo de Tronco Encefálico com estímulo clique e Ichirp. O registro das latências e amplitudes da onda V foi realizado por meio do equipamento Intelligent HearingSystem ­ IHS, nas intensidades: 80, 60, 40 e 20 dB. Resultados: Não foram observadas diferenças estatisticamente significativas quanto às amplitudes da onda V, quando comparado os registros do Potencial Evocado Auditivo de Tronco Encefálico estímulo clique e do Ichirp, nas intensidades de 80 dB (p= 0.11), 60 dB (p=0.14), 40 dB (p=0.96) e 20 dB (p=0.21). Em relação às latências da onda V, foram encontradas diferenças estatísticas significantes entre os estímulos Ichirp e clique, nas seguintes intensidades: 60 dB (p=0,003) e 40 dB (p=0,016). Conclusão: Foram observadas latências maiores para o Potencial Evocado Auditivo de Tronco Encefálico com o estímulo Ichirp; contudo ausência de diferença entre as amplitudes. Houve maior facilidade na marcação da onda V com o estímulo Ichirp.

Purpose: To compare the traces of Brainstem Auditory Evoked Potential with the use of click stimuli and Ichirp in adults with normal hearing. Methods: This is a cross-sectional, analytical, quantitative study. Eleven hearing adults with ages between 20 and 25 years, with normal audiometric thresholds, totaling 22 ears were analyzed. These subjects performed the recording of the Auditory Evoked Potential of Click Brain Trunk and Ichirp. The latency and amplitude of the V wave was recorded through a computer using the Intelligent Hearing System (IHS) equipment at intensities: 80, 60, 40 and 20 dB. Results: No statistically significant differences were observed in V-wave amplitudes when compared to the Ichirp stimulus with the click, in the intensities of 80 dB (p = 0.11), 60 dB (p = 0.14), 40 dB (p = 0.96) and 20 dB P = 0.21). Regarding the latency of the V wave, significant statistical differences between the Ichirp and click stimuli were found in the following intensities: 60 dB (p = 0.003) and 40 dB (p = 0.016). Conclusion: Larger latencies were observed with the Ichirp stimulus.

Objetivo: Analizar los trazados del Potencial Evocado Auditivo de Tronco Encefálico con el uso de los estímulos clic y el Ichirp en adultos con audición normal. Método: Se trata de un estudio transversal, de carácter analítico, cuantitativo. Se analizaron exámenes de Potencial Evocado Auditivo de Tronco Encefálico en 11 adultos oyentes (2 orejas), en el grupo de edad entre 20 y 25 años, sin alteraciones auditivas. Estos sujetos realizaron el registro del Potencial Evocado Auditivo de Tronco Encefálico con estímulo clic y Ichirp. El registro de las latencias y amplitudes de la onda V fue realizado por medio del equipo Intelligent Hearing System - IHS, en las intensidades: 80, 60, 40 y 20 dB. Resultados: No se observaron diferencias estadísticamente significativas en cuanto a las amplitudes de la onda V, cuando comparados a los registros del Potencial Evocado Auditivo de Tronco Encefálico estímulo clic y Ichirp, en las intensidades de 80 dB (p = 0.11), 60 dB (p = 0.14) , 40 dB (p = 0.96) y 20 dB (p = 0.21). En cuanto a las latencias de la onda V, se encontraron diferencias estadísticas significativas entre los estímulos Ichirp y el clic, en las siguientes intensidades: 60 dB (p = 0,003) y 40dB (p = 0,016). Conclusión: Fueron observadas latencias mayores para el Potencial Evocado Auditivo de Tronco Encefálico con el estímulo Ichirp; sin embargo, ausencia de diferencia entre las amplitudes. Hubo mayor facilidad en la marcación de la onda V con el estímulo Ichirp.

Potenciais evocados auditivos de curta e longa latência em indivíduos com disfunção vestibular / Short- and long-latency auditory evoked potentials in individuals with vestibular dysfunction

RESUMO Objetivo Avaliar a via auditiva em nível de tronco encefálico e cortical em indivíduos com disfunção vestibular periférica. Método Participaram do estudo 19 indivíduos, com idade entre 20 e 80 anos que possuíam exames vestibulares sugestivos de Disfunção Vestibular Periférica Deficitária (DVPD) ou Disfunção Vestibular (DV). Os participantes realizaram avaliação da via auditiva por meio dos Potenciais Evocados Auditivos de Tronco Encefálico (curta latência) e dos potenciais P1, N1, P2, N2 e P300 (longa latência). Resultados Nove indivíduos apresentaram diagnóstico de Disfunção Vestibular e 10 de Disfunção Vestibular Periférica Deficitária. A média geral dos potenciais de longa latência dos participantes ficou dentro da normalidade e no de curta latência houve uma média aumentada na latência das ondas III e V da orelha esquerda, bem como no intervalo interpico I-III de ambas as orelhas. Ao relacionar os potenciais auditivos com DV e DVPD, houve significância estatística apenas no intervalo interpico III-V no potencial de curta latência da orelha direita. Ao comparar longa e curta latência nos grupos, houve diferenças nas latências entre DV e DVPD, sem significância estatística. Conclusão Não houve relação significativa de DV e DVPD com os potenciais auditivos, porém, nos potenciais de longa latência, os indivíduos com Disfunção Vestibular apresentaram maior latência em P1, N1, P2, N2 e os indivíduos com Disfunção Vestibular Periférica Deficitária, maior latência no P300. No potencial de curta latência, houve um aumento nas latências absolutas no grupo Disfunção Vestibular e nos intervalos interpicos em Disfunção Vestibular Periférica Deficitária.

ABSTRACT Purpose Evaluate the auditory pathway at the brainstem and cortical levels in individuals with peripheral vestibular dysfunction. Methods The study sample was composed 19 individuals aged 20-80 years that presented exam results suggestive of Peripheral Vestibular Disorder (PVD) or Vestibular Dysfunction (VD). Participants underwent evaluation of the auditory pathway through Brainstem Auditory Evoked Potentials (BAEP) (short latency) and P1, N1, P2, N2, and P300 cortical potentials (long latency). Results Nine individuals presented diagnosis of VD and 10 participants were diagnosed with PVD. The overall average of the long latency potentials of the participants was within the normal range, whereas an increased mean was observed in the short latency of waves III and V of the left ear, as well as in the I - III interpeak interval of both ears. Association of the auditory potentials with VD and PVD showed statistically significant correlation only in the III - V interpeak interval of the right ear for short latency. Comparison between the long and short latencies in the groups showed differences between VD and PVD, but without statistical significance. Conclusion No statistically significant correlation was observed between VD/PVD and the auditory evoked potentials; however, for the long latency potentials, individuals with VD presented higher latency in P1, N1, P2, and N2, where as participants with PVD showed higher latency in P300. In the short latency potentials, there was an increase in the absolute latencies in the VD group and in the interpeak intervals in the PVD group.

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

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

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

Temporal processing and long-latency auditory evoked potential in stutterers.

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

Standard operating procedure: implementation, critical analysis, and validation in the Audiology Department at CESTEH/Fiocruz

ABSTRACT Purpose Evaluate three standard operational procedures (SOPs), regarding the application of the brainstem auditory evoked potential (BAEP) test, implemented by the Audiology Department of the Center for Studies in Occupational Health and Human Ecology (CESTEH) through the application of a questionnaire and to verify whether the SOPs are effective and assess the necessity for improvement. Methods The study was conducted in three phases: in the first phase, eight speech-language pathologists and seven physicians, with no experience in BAEP, were instructed to read and perform each SOP, eventually all individuals evaluated the SOPs by responding to a questionnaire; in the second phase, the questionnaires were analyzed and the three SOP texts were reviewed; in the third phase, nine speech-language pathologists and six physicians, also with no experience in BAEP, read and re-evaluated the reviewed SOPs through a questionnaire. Results In the first phase, difficulties in understanding the texts were found, raising doubts about the procedures; however, every participant was able to perform the procedure as a whole. In the third phase, after the review, all individuals were able to perform the procedures appropriately and continuously without any doubts. Conclusion The assessment of the SOPs by questionnaires showed the need for adaptation in the texts. After the texts were reviewed according to the suggestions of the health professionals, it was possible to observe that the SOPs assisted in the execution of the task, which was conducted without any difficulties or doubts, being regarded effective and ensuring quality to the service offered.

Comparación de las amplitudes y latencias de la onda V del potencial evocado auditivo de tronco cerebral obtenidas a través de estímulos clic y CE-Chirp® / Comparison of brainstem auditory evoked potential wave V amplitudes and latencies obtained through click and CE-Chirp® stimuli

Introducción: El potencial evocado auditivo de tronco cerebral (PEATC) se ha convertido en un procedimiento estándar dentro de la evaluación audiológica. Durante décadas, el estímulo más utilizado ha sido el clic, sin embargo, últimamente se ha propuesto la utilización de estímulos de frecuencia modulada (chirp) para obtener resultados más eficientes. Objetivo: Comparar las amplitudes y las latencias de la onda V del PEATC obtenidas a través de estímulos clic y CE-Chirp® a distintas intensidades. Material y método: Se realizó un estudio de tipo cuantitativo, no experimental, transversal y descriptivo en 17 sujetos a los que se evaluó con un PEATC utilizando estímulos clic y CE-Chirp®. Resultados: Se obtuvieron mayores amplitudes de onda Vpara estímulos CE-Chirp® que para clic, en todas las intensidades evaluadas (80, 60, 40,30 y 20 dBnHL). Se obtuvieron menores latencias en la onda Vpara estímulos CE-Chirp® solo a 80 y 60 dBnHL, mientras que en el resto de las intensidades se obtuvo menores latencias con estímulos clic. Conclusiones: Existen diferencias significativas entre las latencias y amplitudes de la onda V obtenidas con estímulos clic y CE-Chirp®. Mientras los estímulos CE-Chirp® aportan en rapidez en el examen y en la búsqueda del umbral electrofisiológico más preciso, los estímulos clic serían los adecuados al momento de realizar un estudio de topodiagnóstico.

Introduction: The auditory brainstem response (ABR) has become a standard procedure in the audiological evaluation. For decades the most widely used stimulus was the click, but recently the use of chirp stimulus has been proposed for obtain more efficient results. Aim: To compare the amplitudes and latencies of wave V of ABR obtained through click and CE-Chirp® stimuli at different intensities. Material and method: A quantitative, not experimental, transversal and descriptive study was conducted with 17 subjects who were evaluated with ABR using click and CE-Chirp® stimuli. Results: Wave V larger amplitudes were verified for stimulus CE-Chirp®, in all the evaluated intensities (80, 60, 40, 30 and 20 dBnHL). Shorter latencies of wave V were obtained for CE-Chirp® stimuli only at 80 and 60 dBnHL, while it was found that the remaining intensities showed lower latencies with click stimuli. Conclusions: There are significant differences between latencies and amplitudes of the wave V obtained with CE-Chirp® and click stimuli. While the CE-Chirp® stimuli provides faster results for most accurate electrophysiological threshold, click stimuli would be appropriate to conduct site of the lesion testing.

Comparison of Pre-Attentive Auditory Discrimination at Gross and Fine Difference between Auditory Stimuli

Abstract Introduction Mismatch Negativity is a negative component of the event-related potential (ERP) elicited by any discriminable changes in auditory stimulation. Objective The present study aimed to assess pre-attentive auditory discrimination skill with fine and gross difference between auditory stimuli. Method Seventeen normal hearing individual participated in the study. To assess preattentive auditory discrimination skill with fine difference between auditory stimuli, we recorded mismatch negativity (MMN) with pair of stimuli (pure tones), using /1000 Hz/ and /1010 Hz/ with /1000 Hz/ as frequent stimulus and /1010 Hz/ as infrequent stimulus. Similarly, we used /1000 Hz/ and /1100 Hz/ with /1000 Hz/ as frequent stimulus and /1100 Hz/ as infrequent stimulus to assess pre-attentive auditory discrimination skill with gross difference between auditory stimuli. The study included 17 subjects with informed consent. We analyzed MMN for onset latency, offset latency, peak latency, peak amplitude, and area under the curve parameters. Result Results revealed that MMN was present only in 64% of the individuals in both conditions. Further Multivariate Analysis of Variance (MANOVA) showed no significant difference in all measures of MMN (onset latency, offset latency, peak latency, peak amplitude, and area under the curve) in both conditions. Conclusion The present study showed similar pre-attentive skills for both conditions: fine (1000 Hz and 1010 Hz) and gross (1000 Hz and 1100 Hz) difference in auditory stimuli at a higher level (endogenous) of the auditory system.