Purpose
To analyze the variability of the amplitude and latency of the P3 cognitive potential in normal individuals, the condition test and retest, in the period of 7 days.
Methods
We evaluated 32 subjects, with ages between 18 and 25 years, 20 females and 12 males, without hearing complaints. Were submitted to audiologic evaluation and cortical potential.
Results
The mean values of latency and amplitude for the P3 obtained in this study were of 314.78 ms and 312.40 ms for latency and 5.04 μV and 4.58 μV, for amplitude, in positions Cz and Fz, respectively. No significant difference was found when compared to the latency and amplitude, in the test-retest reliability, with the fixing of the electrodes in Cz and Fz. There was no difference for the latency and amplitude of P3 in all the modalities studied: gender, fixation of the electrodes (Cz and Fz) and condition test and retest. For the latency of the P3 in the female gender and condition of test and retest, there was significant difference.
Conclusion
The mean values of latency and amplitude found in this study were 313.6 ms and 4.81 μV, respectively. The values of latency and amplitude did not vary according to the position of the electrodes (Cz and Fz) and regarding the condition test as retest. There was a significant difference for the female gender when compared in condition test and retest.The mean difference of the latency of P3 in condition of reassessment was 10.50 ms (Fz) and 15.25 ms (Cz) for the female gender and of 6.00 ms (Fz) and 5.83 ms (Cz) for the male gender.
Evoked potentials; Event-related potencials; P300; Evoked potentials; Auditory; Hearing; Auditory perception