title: Test-Retest of Long Latency Auditory Evoked Potentials (P300) with Pure Tone and Speech Stimuli.
abstract: IntroductionLong latency auditory evoked potentials, especially P300, have been used for clinical evaluation of mental processing. Many factors can interfere with Auditory Evoked Potential - P300 results, suggesting large intra and inter-subject variations.ObjectiveThe objective of the study was to identify the reliability of P3 components (latency and amplitude) over 4-6 weeks and the most stable auditory stimulus with the best test-retest agreement.MethodsTen normal-hearing women participated in the study. Only subjects without auditory processing problems were included. To determine the P3 components, we elicited long latency auditory evoked potential (P300) by pure tone and speech stimuli, and retested after 4-6 weeks using the same parameters. We identified P300 latency and amplitude by waveform subtraction.ResultsWe found lower coefficient of variation values in latency than in amplitude, with less variability analysis when speech stimulus was used. There was no significant correlation in latency measures between pure tone and speech stimuli, and sessions. There was a significant intrasubject correlation between measures of latency and amplitude.ConclusionThese findings show that amplitude responses are more robust for the speech stimulus when compared with its pure tone counterpart. The P300 indicated stability for latency and amplitude measures when the test-retest was applied. Reliability was higher for amplitude than for latency, with better agreement when the pure tone stimulus was used. However, further research with speech stimulus is needed to clarify how these stimuli are processed by the nervous system.
authors.affiliation: Department of Phonoaudiology, Escola Paulista de Medicina - UNIFESP, São Paulo, SP, Brazil; Department of Phonoaudiology Specialization, Universidade Federal Fluminense, Nova Friburgo, Rio de Janeiro, RJ, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Perez
authors.affiliation: Department of Phonoaudiology, Escola Paulista de Medicina - UNIFESP, São Paulo, SP, Brazil.
authors.forename: Karin
authors.initials: K
authors.lastname: Ziliotto
authors.affiliation: Department of Phonoaudiology, Escola Paulista de Medicina - UNIFESP, São Paulo, SP, Brazil.
authors.forename: Liliane Desgualdo
authors.initials: LD
authors.lastname: Pereira
keywords: auditory perception; event-related; evoked potentials; potentials; reliability