Accumulated reserves hold back age-related neural compensation in speech-in-noise perception

Abstract

AbstractRecruitment of neural activity or functional connectivity is commonly observed in older adults but poorly understood. We measured brain activity with fMRI during speech-in-noise tasks and assessed whether accumulated reserve accrued through musical training bolsters or holds back age-related neural compensation. Older musicians exhibited less upregulation of task-induced functional connectivity than older non-musicians in dorsal regions, which predicted better behavioral performance in older musicians. The findings suggest that accumulated reserve may hold back neural recruitment. Besides functional connectivity strength, we also found that older musicians showed more youth-like fine spatial patterns of functional connectivity than older non-musicians. However, benefits from visual lip movements were not specific to either hypothesis. Aligning with enhanced benefits in behavioral performance, older musicians showed more extensive functional connectivity enhancement, specifically in the right hemisphere, than older non-musicians. Our findings enlightened the intricate interplay between accumulated reserve and age-related neural compensation during speech in noise perception.