Aging and Hearing Loss in Emotional Prosody Processing: Divergent Neural Adaptation and Behavioral Performance

Emotional prosody perception is vulnerable in later adulthood, yet the contributions of central aging and peripheral hearing loss remain unclear. Across two experiments, we combined event-related potentials (ERPs) , time-frequency analyses and behavioral measures to examine how aging and hearing sensitvity shape emotional prosody processing. Experiment 1 used acoustically matched speech and nonspeech stimuli in a passive oddball paradigm to assess preattentive processing. Experiment 2 examined explicit emotion identification and implicit stimulus judgment to evaluate goal-directed performance and its associations with neural responses. Aging was associated with reduced neural differentiation between emotions and lower behavioral efficiency, alongside enhanced P3a amplitude. Older adults also responded more slowly than younger adults during emotion identification. Hearing sensitivity showed no significant main effect on accuracy or reaction time, despite associations with delayed early neural processing and stronger theta- and alpha-band activity. Hearing-related neural effects were most evident in older adults and varied across emotions and stimulus types. Brain–behavior associations were selective: reduced mismatch negativity (MMN) was associated with slower responses during stimulus identification, whereas longer MMN latencies were associated with lower accuracy and slower responses during emotion identification. These findings indicate that aging and hearing loss have distinct yet interacting associations with emotional prosody processing, with neural responses not necessarily corresponding to behavioral performance. We propose an “asymmetric adaptation” account in which neural responses to degraded auditory input reorganize selectively across processing stages and contexts, potentially explaining this neural-behavioral divergence and informing more sensitive assessment of socioemotional communication in later adulthood.