RESUMO
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.
RESUMO
Introduction Velopharyngeal sphincter is a portion of the muscle of the palatopharyngeal arch that is capable of separating the oral cavity from the nasal cavity. It has not been determined yet whether voice intensity has an influence on this capacity. Velopharyngeal sphincter closure is accomplished by elevating and retracting the soft palate at the same time as the nasopharyngeal walls are constricted. Objective This study aims to correlate voice intensity with velopharyngeal sphincter closure in individuals without velopharyngeal dysfunction and patients with cleft lip and palate. Methods We conducted a cross-sectional, comparative, and contemporary study. The sample consisted of 16 individuals in the control group and 16 individuals in the study group. Patients underwent instrumental assessment, which we subsequently analyzed using a computer program, and a brief medical history review. The mean age of the control group was 27.6 years, whereas the mean age of the case group was 15.6 years. Results Cases showed higher voice intensity in regular and weak fricative sentences when compared with controls. There was no agreement on the analysis of the instrumental assessment between the assessors and the computer program. Regardless of voice intensity, the computer program demonstrated a similar closure pattern. Conclusion The computer program showed similar closure pattern for the three levels of intensity. There was no agreement between the three assessors and the closure pattern determined by the computer program. There was no statistically significant correlation between voice intensity and degree of velopharyngeal sphincter closure.