Neural signatures of temporal regularity processing in sounds differ between younger and older adults.
Sensitivity to temporal regularity (e.g., recurring modulation in amplitude) is crucial for speech perception. Degradation of the auditory periphery due to aging and hearing loss may lead to increased responsiveness to sound in the auditory cortex, with potential consequences for the processing of temporal regularities. We used electroencephalography recorded from younger (19-33 years) and older adults (55-76 years) to investigate whether younger and older listeners differ in responsiveness to sound and sensitivity to amplitude modulation in sounds. Aging was associated with reduced adaptation in the auditory cortex, suggesting an age-related increase in responsiveness. Furthermore, neural synchronization in the auditory cortex to 4-Hz amplitude-modulated narrow-band noises was enhanced in ∼30% of older individuals. Despite enhanced responsiveness and synchronization in the auditory cortex, sustained neural activity (likely involving auditory and higher-order regions) in response to amplitude modulation was absent in older people. Aging appears to be associated with over-responsiveness to amplitude modulation in the auditory cortex, but with diminished regularity sensitivity in higher-order areas.
['Herrmann|Björn|B|', 'Buckland|Chad|C|', 'Johnsrude|Ingrid S|IS|']
D000161:Acoustic Stimulation D000328:Adult D000368:Aged D001303:Auditory Cortex D001307:Auditory Perception D004569:Electroencephalography D005072:Evoked Potentials, Auditory D005260:Female D034381:Hearing Loss D006801:Humans D008297:Male D008875:Middle Aged D013016:Sound D055815:Young Adult
Aging Amplitude modulation Neural synchronization Neural adaptation Sustained activity