Reduced neural sensitivity to musical tempo despite enhanced neural tracking of musical features in older adults

A substantial body of prior research has focused on how aging affects the neural processing of speech, whereas less is known about how older adults encode naturalistic music. Here, we investigated whether the neural tracking of different features in naturalistic music differs between age groups. Younger and older adults (both sexes) listened to excerpts of naturalistic music with different tempi (1-4 Hz) while electroencephalography (EEG) was recorded. The results show an age-related enhancement of neural responses to sound onsets, suggesting a loss of inhibition in the aged auditory cortex that is thought to arise from peripheral decline. This hyperresponsiveness generalized to the neural tracking of multiple features (amplitude envelope, onsets, beat, and spectral flux) in naturalistic music. Crucially, older adults showed reduced sensitivity of early brain responses (0-130 ms) to tempo: Unlike younger adults, whose neural tracking decreased systematically with increasing tempo, older listeners maintained uniformly enhanced tracking across tempi. Spectral flux best predicted tempo- related changes in EEG activity, but this was reduced in older compared to younger adults. In sum, the current study demonstrates that cortical hyperactivity in aging enhances the tracking of different features during naturalistic music listening but impairs the sensitivity to musical tempo. This dissociation highlights the complex changes and functional consequences of auditory aging related to the processing of naturalistic music. SIGNIFICANCE STATEMENTHow aging affects the encoding of ecologically-valid, naturalistic music is not well understood, although music is an important part of older peoples lives. Here, we used electroencephalography and temporal response function approaches to investigate how younger and older adults encode different features of naturalistic music at different tempi (1 to 4 Hz). The results reveal a fundamental trade-off in the aging auditory system: enhanced neural tracking of acoustic features coexists with declined sensitivity to musical tempo. This dissociation between hyperactivity for feature encoding and impaired temporal sensitivity highlights complex changes in the aged auditory system that can have implications for music perception in older adulthood.