Related Experiment Video
Updated: Aug 9, 2026
Performing Intracochlear Electrocochleography During Cochlear Implantation
Published on: March 8, 2022
Cochlear Implant and Age-Dependent Cortical Dynamics: A Multilevel Meta-Analysis of Mismatch Negativity Latency and
Zhe Yang1,2, Yusen Fu3,2, Rui Zhu1
1Shanghai Yangzhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), School of Medicine, Tongji University, Shanghai, China.
Objectives:
This study quantitatively assessed the neurophysiological differences in mismatch negativity (MMN) responses between cochlear implant (CI) users and normal hearing (NH) listeners. Through meta-analysis, we examined effect size differences and statistical significance in MMN latency and amplitude between these groups. Age-stratified subgroup analyses further explored MMN morphology variations in adults and children to evaluate age-related outcomes of cochlear implantation.
Design:
Systematic searches were conducted in PubMed, Embase, Medline (Ovid), and Cochrane Library up to February 24, 2025. Records (published in English) comparing MMN latency and amplitude between CI users and NH listeners were included. Eligible studies were analyzed using multilevel modeling. Publication bias was assessed using funnel plots and Egger's test.
Results:
The meta-analysis incorporated 21 latency and 23 amplitude data points from 11 studies. Pooled analyses revealed significantly prolonged MMN latency and reduced amplitude in CI users compared to NH listeners. Subgroup analyses demonstrated that pediatric CI users showed no statistically significant MMN differences (latency or amplitude) relative to NH peers, with low heterogeneity. In contrast, adult CI users exhibited significantly smaller MMN amplitudes (low heterogeneity) and longer latencies (high heterogeneity) compared to NH adults.
Conclusions:
This study confirms that adult CI users exhibit slower neural processing speeds and weaker neural response magnitudes than adult NH listeners, as reflected in MMN latency and amplitude. It quantitatively validates MMN as an objective electrophysiological assessment tool for auditory function in CI users. Furthermore, the observed group-level differences between pediatric and adult cohorts highlight age as a critical factor. However, more evidence is needed to conclude that earlier implantation preserves MMN morphology long-term. With caution, the review acknowledges potential limitations, including possible publication bias from unpublished nonsignificant studies and high heterogeneity in some outcomes.
