Behavioral Perception and Neural Correlates of Categorical Perception in Cochlear Implant Users
10.3342/kjorl-hns.2017.00703
- Author:
Jeong Hye PARK
1
;
Ji Hye HAN
Author Information
1. Laboratory of Brain & Cognitive Sciences for Convergence Medicine, Hallym University College of Medicine, Anyang, Korea. slphan12@gmail.com
- Publication Type:Original Article
- Keywords:
Categorical perception;
Cochlear implant;
N1-P2 cortical auditory evoked potentials;
Temporal processing;
Voice onset time
- MeSH:
Cochlear Implants;
Cues;
Electroencephalography;
Evoked Potentials, Auditory;
Methods;
Speech Perception;
Voice
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2018;61(1):15-23
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND AND OBJECTIVES: Although many cochlear implant (CI) recipients receive significant benefits from using the implants, speech perception ability is still known to vary among CI users, and the variability is closely related to the ability of users to process temporal information. As one of the important temporal cues for speech perception in CI users, voice onset time (VOT) can be used to examine behavioral perception and neural correlates of temporal processing. In this study, we measured categorical perception and N1-P2 cortical auditory evoked potentials (CAEPs) using a /ba/-/pa/ VOT continuum in CI users as well as in normal-hearing (NH) listeners. SUBJECTS AND METHOD: Ten CI subjects and 11 NH controls participated in syllable identification tasks and in electroencephalography recording. CI subjects were divided into two groups, which were ‘good’ and ‘poor’ performers based on their speech perception scores. The stimuli used in both experiments were a synthetic /ba/-/pa/ VOT continuum. The identification boundary and N1-P2 peak-to-peak amplitude were measured for each subject group. RESULTS: Behavioral results revealed that poor CI performers had a delayed identification boundary compared to NH listeners and good CI performers. However, N1-P2 peak-to-peak amplitudes in both good and poor CI performers were significantly smaller than those in NH group. CONCLUSION: N1-P2 amplitudes reflected decreased auditory cortical activity of temporal cues in CI users. The categorical perception of good CI performers was similar to that of NH listeners, whereas their cortical responses were decreased to the level similar to that of poor CI performers. This finding indicates that CAEPs would be more sensitive to altered temporal processing of CI users than to behavioral measures.
