Introduction: Auditory Evoked Potentials are electrical responses that occur in the central auditory pathways, resulting from acoustic stimulation. The use of speech stimuli to elicit the response of these potentials allows to understand information about speech coding and decoding in the central nervous system. Purpose: To compare the Long Latency Auditory Evoked Potential of two different speech stimuli. Methods: Thirty healthy school children of both genders, aged between 8 and 12 years, participated in the study. For the auditory evoked potentials, different speech stimuli were used for the auditory discrimination: Test 1 /ba/ x /da/ and Test 2 /pa/ x /da/. The stimuli were randomly presented: 20% infrequent and 80% frequent. The school children participated in an active auditory task and said [da] to identify the infrequent stimuli. The normality of the data was determined using the Shapiro-Wilk test. To compare the mean with Test 1 and Test 2, stimulation was performed using Student t test. Results: There was a significant difference in P3 latency in the right ear, P2 amplitude in the right ear and P3 amplitude in the left ear. Longer values occurred with stimulus /ba/ x /da/. Conclusion: The responses of long latency auditory evoked potentials vary depending on the stimulus and care in the analysis when using speech stimuli in the evaluation.

Results:In this study, there was 100% detectability of the Na, Pa, and Nb components and interamplitude Na-Pa. This study compared different electrode leads, and there was no signifi cant difference between the different electrode positions studied for the right and left ears in the studied population. Conclusion:It was concluded that the examination of middle-latency evoked potential is steady and feasible for the studied age group regardless of electrode position. ORIGINAL RESEARCH 369 J Hum Growth Dev. 26(3): 368-373. Doi: http://dx.doi.org/10.7322/jhgd.122905 J Hum Growth Dev. 2016; 26(3): 368-373 Middle Latency Auditory Evoked Potential in child population J Hum Growth Dev. 26(3): 368-373. Doi: http://dx.doi.org/10.7322/jhgd.122905 J Hum Growth Dev. 2016; 26(3): 368-373 Middle Latency Auditory Evoked Potential in child population

Introduction  The P300 test requires well-defined and unique criteria, in addition to training for the examiners, for a uniform analysis of studies and to avoid variations and errors in the interpretation of measurement results. Objectives  The objective of this study is to verify whether there are differences in P300 with and without subtraction of traces of standard and nonstandard stimuli. Method  We conducted this study in collaboration with two research electrophysiology laboratories. From Laboratory 1, we selected 40 tests of subjects between 7–44 years, from Laboratory 2, we selected 83 tests of subjects between 18–44 years. We first performed the identification with the nonstandard stimuli; then, we subtracted the nonstandard stimuli from the standard stimuli. The examiners identified the waves, performing a descriptive and comparative analysis of traces with and without subtraction. Results  After a comparative analysis of the traces with and without subtraction, there was no significant difference when compared with analysis of traces in both laboratories, within the conditions, of right ears ( p  = 0.13 and 0.28 for differences between latency and amplitude measurements) and left ears ( p  = 0.15 and 0.09 for differences between latency and amplitude measurements) from Laboratory 1. As for Laboratory 2, when investigating both ears, results did not identify significant differences ( p  = 0.098 and 0.28 for differences between latency and amplitude measurements). Conclusion  There was no difference verified in traces with and without subtraction. We suggest the identification of this potential performed through nonstandard stimuli.

Introduction Any type of sensory deprivation in childhood resulting from conductive hearing loss may impair the development of peripheral and central auditory pathway structures with negative consequences for binaural processing. Objective To characterize and compare monoaural and binaural auditory responses in neonates and children without and with a history of recurrent otitis. Methods The study included participants from 0 to 8 years and 11 months old, in good general health conditions, of both genders, divided into a control group, with no history of otitis, and a study group, with history of recurrent otitis. Cortical potential with speech stimulus /ba/-/da/ was used as collection procedure. The arithmetic calculation of the 512 points of the wave was performed to obtain the grand average of the waves of the subjects in both groups. The Shapiro-Wilk and mixed repeated measures analysis of covariance (ANCOVA) statistical tests were performed to analyze the group effect, the condition, and the interaction (group versus condition) controlling the effect of the age-sex covariable. Results There was a statistically significant difference between the groups for all latency values; and for the P1, N1, P2, and N2 latencies, the differences between the groups occurred in the three analyzed conditions (right and left ears and binaural), revealing the influence of sensory deprivation. There were no significant differences in relation to wave amplitudes. Conclusion There are differences in the cortical potential with speech stimuli and in the binaural interaction component of children with and without history of recurrent otitis.