Audiovisual speech perception in Mandarin cochlear implant users across age and listening conditions

To investigate how visual cues influence speech recognition in Mandarin-speaking cochlear implant (CI) users and examine age-related differences in audiovisual (AV) integration across varying sound intensities and noise conditions.

A cross-sectional observational study comparing performance in visual-only (VO), audio-only (AO), and AV conditions using standardized Mandarin monosyllabic word and sentence tests.

Seventy-two participants were recruited, including 40 CI users (22 children, 18 adults) and 32 normal-hearing (NH) controls (16 children, 16 adults). All CI users were unilateral recipients of Cochlear™ Nucleus® devices.

AV input significantly enhanced word recognition in CI users, particularly under degraded conditions (low intensity or high noise), consistent with the principle of inverse effectiveness. CI children outperformed adults in AV word tasks, whereas adults had better sentence comprehension. VO performance was comparable between CI and NH groups, suggesting effective visual compensation among CI users. The most pronounced AV benefit was observed at 0 dB signal-to-noise ratio, where AV sentence scores approached AO performance at +5 dB.

AV cues play a critical role in speech perception for Mandarin-speaking CI users, especially under acoustically challenging conditions. Age-specific patterns in AV integration suggest differential reliance on visual input and linguistic strategies. These findings support the inclusion of AV and VO tasks in clinical assessments and underscore the importance of multimodal rehabilitation approaches, particularly for pediatric CI users.