Spatial Hearing and Aging Effects on Mandarin Focus Comprehension in Complex Listening Environments

This study examined aging effects in Mandarin prosodic focus comprehension, specifically investigating whether postfocus compression (PFC) and spatial separation between speech and noise both serve as effective perceptual cues for older listeners compared to younger counterparts in complex listening environments.

Twenty younger and 20 older native Mandarin listeners were recruited to identify implied contrastive meaning via prosodic cues in focus comprehension tasks conducted in an acoustically treated semi-anechoic chamber. Stimuli included five focus types (subject initial focus [IF], adverbial medial focus [MF1], verb medial focus [MF2], object final focus [FF], and neutral focus [NF]). Target speech was presented from the front (0° azimuth) in quiet and with cafeteria noise at 0 dB and -10 dB SNR under two spatial configurations: colocated (noise at 0° azimuth) and separated (noise at 90° azimuth). Linear mixed-effects models analyzed accuracy, spatial release from masking (SRM), and confusion patterns, with pure-tone average as a covariate.

Younger listeners outperformed older listeners (93.6% vs. 55.5% overall accuracy). Older listeners showed better performance with PFC focuses (IF, MF1, MF2) over non-PFC types (FF, NF) across conditions. Noise-induced performance deficits were more severe in colocated setups. Despite older listeners' overall lower performance, the relative benefits from SRM were comparable between age groups, with greater spatial release effects at -10 dB SNR. Confusion matrix analysis revealed systematic errors for focused speech perception and random errors for unfocused speech perception (NF) among both age groups.

PFC serves as a robust cue for focus comprehension even for aging listeners. Crucially, while absolute performance declines with age, the relative benefit of SRM for prosodic processing remains relatively preserved even in complex listening environments. These findings highlight the resilience of certain spatial hearing mechanism in aging, pointing to the importance of spatial cues in designing interventions for age-related communication challenges.

https://doi.org/10.23641/asha.32177424.