Aging alters the neural representation of speech cues.
Age-related deficits in speech understanding are well documented. Because speech is a complex signal, containing time-varying acoustic cues, it is frequently hypothesized that aging adversely affects the ability to process temporal cues. This study examined the neural representation and perception of voice-onset-time, a temporal cue that distinguishes voiced /b/ from voiceless /p/ sounds. We found that older adults had more difficulty than younger listeners discriminating voice-onset contrasts. In addition, these same speech stimuli evoked abnormal neural responses in older adults. That is, compared with younger listeners, N1 and P2 long-latency auditory evoked responses were prolonged for older adults. Collectively, these results suggest speech perception difficulties described by older adults may be related to age-related changes regulating excitatory and inhibitory processes.
Tremblay
Kelly L
KL
Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98105, USA. tremblay@u.washington.edu
Piskosz
Michael
M
Souza
Pamela
P
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001303:Auditory Cortex / Q000503:physiopathology*; D001304:Auditory Diseases, Central / Q000503:physiopathology*; D003463:Cues; D005072:Evoked Potentials, Auditory / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D013063:Speech Discrimination Tests; D013064:Speech Disorders / Q000503:physiopathology*; D013065:Speech Intelligibility / Q000502:physiology; D013067:Speech Perception / Q000502:physiology*