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Long-latency auditory evoked potentials in sound field in normal-hearing children

ABSTRACT

Purpose:

To characterize the Long-Latency Auditory Evoked Potentials (LLAEP) (P1, N1, P2, N2, P300) with acoustic stimuli presented in sound field system in children with normal hearing, as well as to verify the stability of these potentials.

Methods:

This prospective, longitudinal study comprised 17 children with ages between 6 and 13 years and hearing thresholds within normal. The LLAEP P1, N1, P2, N2, P300 were recorded with speech stimuli and tone burst presented in sound field system, in three different moments: initial assessment (M0), three months after the initial assessment (M3), and nine months after the initial assessment (M9).

Results:

When the speech stimuli was used, there was a decrease in the latency values of components P1 (M0xM3/M0xM9/M0xM3xM9) and P2 (M0xM9), as well as an increase in the amplitude of P300 (M0xM3) over time. With the tone bust stimuli, it was verified a decrease in the latency values of P300 (M0xM9) over time.

Conclusion:

it was possible to identify the components of the LLAEP in most individuals. The P1, N1, P2, N2 (tone burst) and N1 and N2 (speech) did not change their latencies and amplitudes between the different moments of evaluation, suggesting stability of this potential in the period of 9 months. The P300 was the component most sensitive to the time intervals considered, since it presented modifications over time that indicated maturation of the central auditory nervous system. The latencies of all components obtained with speech stimulus were higher than with tone bursts, indicating that different stimuli generate different cortical responses.

Keywords:
Evoked potentials, Auditory; Event-related potentials, P300; Hearing; Child; Auditory threshold

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