ABSTRACT
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.
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 182.4 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.
ABSTRACT
RESUMO Introdução Mismatch Negativity (MMN) é um potencial eletrofisiológico que mede a habilidade do cérebro em discriminar sons, independente da capacidade atencional e comportamental. Por ser uma medida objetiva e de fácil utilização, torna-se promissora no estudo da investigação do processamento auditivo em crianças. Objetivo Verificar a aplicabilidade do Mismatch Negativity na população infantil. Estratégia de pesquisa Conduziu-se uma busca nos meses de agosto e setembro de 2016, usando os descritores Evoked Potentials, Auditory AND Children, Event-related Potential AND Children e Electrophysiology AND Children, nas bases de dados Portal BVS (MEDLINE, IBECS e LILACS) e SciELO. Critérios de seleção Foram selecionados artigos em português, inglês e espanhol, publicados até setembro de 2016, sem limitação de data inicial, cuja abordagem do Mismatch Negativity fosse com a população infantil. Resultados A estratégia de busca resultou na seleção de 23 artigos, classificados como artigos originais. Os estudos evidenciaram diversas aplicabilidades do MMN em crianças, incluindo transtorno do espectro autista, transtornos do processamento auditivo, fissura labiopalatina, prematuridade e distúrbio específico de linguagem, sendo a maioria em dislexia. Conclusão Apesar da grande variabilidade envolvida nas medidas de realização do MMN, existe uma ampla aplicabilidade clínica desse potencial eletrofisiológico na população infantil.
ABSTRACT Introduction Mismatch Negativity (MMN) is an electrophysiological potential that evaluates the brain's capacity to discriminate sounds, regardless of attentional and behavioral capacity. Because it is an objective and user-friendly measure, it becomes promising in the study of auditory processing research in children. Purpose To verify the applicability of Mismatch Negativity (MMN) in children. Research strategy A search was conducted in August and September 2016 using the descriptors Evoked Potentials, Auditory AND Children, Event-related Potential AND Children and Electrophysiology AND Children in bibliographic collection of the electronic databases Portal BVS (Medline, IBECS and LILACS) and SciELO. Selection criteria The selection of articles was carried out in Portuguese, English and Spanish published up to September 2016 without initial date limitation and whose approach to Mismatch Negativity was with the child population. Results The search strategy resulted in the selection of 23 articles classified as original articles. The studies evidenced several applications of MMN in children, including autism spectrum disorder, auditory processing disorders, cleft lip and palate, prematurity, and language-specific disorder, being the majority of them in dyslexia. Conclusion Despite the great variability involved in the measures of MMN, there is a wide clinical applicability of this electrophysiological potential in the infant population.