Auditory Evoked Potential Mismatch Negativity in Normal-Hearing Adults

Abstract

Introduction Mismatch Negativity (MMN) corresponds to a response of the central auditory nervous system. Objective The objective of this study is to analyze MMN latencies and amplitudes in normal-hearing adults and compare the results between ears, gender and hand dominance. Methods This is a cross-sectional study. Forty subjects participated, 20 women and 20 men, aged 18 to 29 years and having normal auditory thresholds. A frequency of 1000Hz (standard stimuli) and 2000Hz (deviant stimuli) was used to evoked the MMN. Results Mean latencies in the right ear were 169.4ms and 175.3ms in the left ear, with mean amplitudes of 4.6µV in the right ear and 4.2µV in the left ear. There was no statistically significant difference between ears. The comparison of latencies between genders showed a statistically significant difference for the right ear, being higher in the men than in women. There was no significant statistical difference between ears for both right-handed and left-handed group. However, the results indicated that the latency of the right ear was significantly higher for the left handers than the right handers. We also found a significant result for the latency of the left ear, which was higher for the right handers. Conclusion It was possible to obtain references of values for the MMN. There are no differences in the MMN latencies and amplitudes between the ears. Regarding gender, the male group presented higher latencies in relation to the female group in the right ear. Some results indicate that there is a significant statistical difference of the MMN between right- and left-handed individuals.

Mismatch Negativity Occurrence with Verbal and Nonverbal Stimuli in Normal-Hearing Adults

“…However, it contradicts other findings, 4 which found lower latencies and higher amplitudes in women for stimuli that differed in frequency, although they did not perform gender analysis. And yet another study, 27 which also showed a difference between genders regarding latency, being higher for men.For amplitude, no significant difference was found, as occurred in the current study.…”

“…However, other authors showed an even larger average amplitude. 27 When evaluating illiterate individuals, and after 1 year of study, Schaadt et al observed an increase in the amplitude with verbal stimulation after literacy. 32 However, the results were lower than those found in the present study, probably because the current sample had at least 8 years of schooling, which may have contributed to the amplitude being greater than that presented in the aforementioned study.…”

Mismatch Negativity Elicited by Verbal and Nonverbal Stimuli: Comparison with Potential N1

“…1,2 These potentials are most commonly used to evaluate auditory abilities objectively. [3][4][5] The long latency auditory evoked potential (LLAEP) record shows a sequence of negative (N) and positive (P) peaks, among which are the potential P1-N1-P2-N2-P300 and mismatch negativity (MMN). The P1-N1-P2 complex represent the corti-cal potentials and provide information on the arrival on the auditory stimuli to the cortex.…”

Aplicabilidade do Mismatch Negativity na população infantil: revisão sistemática de literatura

“…This potential has as main generator the auditory cortex and receives contributions from the frontal cortex, thalamus and hippocampus (8) . It is a cerebral automatic response, promoted by any discriminable change in some repetitive aspect of auditory stimulation (6,9,10,11) , indicating a mismatch between the new sensory input, in relation to a stored standard stimulus In the short-term auditory sensorial memory (1,6,12) . MMN is obtained by subtracting the response evoked by the rare stimulus in relation to the standard stimulus presented (4,9,10) , and the result appears as a wave with negativity (6,9) .…”

“…MMN is a procedure that has a good correlation with the results found in subjective evaluations that, similarly, analyzed the ability of auditory discrimination (6,13) . Its main advantage, compared to other exams, is that the wave appears independently of the attention of the individual to the presented sound stimuli (1,4,6,7,10,14) , that is, it can be registered without the influence of the attention of the subject and without requiring tasks, making it particularly suitable for clinical studies in evaluating the child population (4,11) . Studies have shown that MMN can be a very useful evaluative means for recognizing changes in language (4,9) in children due to the possibility of assessing auditory processing deficit at an early age (9,13,15) Capable of analyzing neurophysiological plasticity (13) .…”