RESUMO
Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.
RESUMO
Introduction Cochlear implantation has been considered a viable option to restore hearing perception in adults with severe to profound postlingual hearing loss. Objectives To analyze behavioral hearing responses and P300 latency and amplitude measurements in adults with bilateral sensorineural hearing loss at two phases, first when they were using hearing aids (HAs) and, then, after 12 months of cochlear implant (CI) use. The association between behavioral and electrophysiological evaluations was explored, as it is believed that the study of auditory processing with different hearing devices can contribute to future CI adjustments and fittings, especially for patients who cannot give subjective feedback (such as small children and individuals with multiple disabilities). Methods Prospective comparative study (Ethical approval 11489/2014). Twelve adults were assessed, 7 males and 5 females, in the 22 to 76 years old age range, who had undergone CI surgery after HA experience. Results The analyses showed an improvement of hearing thresholds when patients started using CIs. Comparing data from P300 latency measurements, there was an increase of the P300 wave post-CI at Cz and Fz. Regarding the amplitude, P300 mean values decreased at Cz, but increased at Fz. There was no significant correlation between behavioral and electrophysiological assessment and the variables age, gender, auditory deprivation, and electronic device used. Conclusion There was a significant improvement of hearing thresholds after twelve months of CI experience. The mean latency values of P300 after 12 months of CI use increased at Cz and Fz, while mean amplitude values decreased at Cz and increased at Fz.
RESUMO
Abstract Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.