Human temporal auditory acuity as assessed by envelope following responses.
Temporal auditory acuity, the ability to discriminate rapid changes in the envelope of a sound, is essential for speech comprehension. Human envelope following responses (EFRs) recorded from scalp electrodes were evaluated as an objective measurement of temporal processing in the auditory nervous system. The temporal auditory acuity of older and younger participants was measured behaviorally using both gap and modulation detection tasks. These findings were then related to EFRs evoked by white noise that was amplitude modulated (25% modulation depth) with a sweep of modulation frequencies from 20 to 600 Hz. The frequency at which the EFR was no longer detectable was significantly correlated with behavioral measurements of gap detection (r = -0.43), and with the maximum perceptible modulation frequency (r = 0.72). The EFR techniques investigated here might be developed into a clinically useful objective estimate of temporal auditory acuity for subjects who cannot provide reliable behavioral responses.
Purcell
David W
DW
The Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Ontario M6A 2E1, Canada. d.purcell@utoronto.ca
John
Sasha M
SM
Schneider
Bruce A
BA
Picton
Terence W
TW
D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001309:Auditory Threshold / Q000502:physiology*; D003056:Cochlear Nerve / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008144:Loudness Perception / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010700:Phonetics; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013061:Speech Acoustics; D013067:Speech Perception / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*