Effects of moderate cochlear hearing loss on the ability to benefit from temporal fine structure information in speech.
Speech reception thresholds (SRTs) were measured with a competing talker background for signals processed to contain variable amounts of temporal fine structure (TFS) information, using nine normal-hearing and nine hearing-impaired subjects. Signals (speech and background talker) were bandpass filtered into channels. Channel signals for channel numbers above a "cut-off channel" (CO) were vocoded to remove TFS information, while channel signals for channel numbers of CO and below were left unprocessed. Signals from all channels were combined. As a group, hearing-impaired subjects benefited less than normal-hearing subjects from the additional TFS information that was available as CO increased. The amount of benefit varied between hearing-impaired individuals, with some showing no improvement in SRT and one showing an improvement similar to that for normal-hearing subjects. The reduced ability to take advantage of TFS information in speech may partially explain why subjects with cochlear hearing loss get less benefit from listening in a fluctuating background than normal-hearing subjects. TFS information may be important in identifying the temporal "dips" in such a background.
Hopkins
Kathryn
K
Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom. kh311@cam.ac.uk
Moore
Brian C J
BC
Stone
Michael A
MA
D000161:Acoustic Stimulation / Q000523:psychology*; D000328:Adult; D001302:Audiometry, Speech; D003463:Cues; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology* / Q000523:psychology; D006801:Humans; D010470:Perceptual Masking / Q000502:physiology; D011571:Psychoacoustics; D013018:Sound Spectrography; D013061:Speech Acoustics; D013065:Speech Intelligibility; D013067:Speech Perception / Q000502:physiology*; D013069:Speech Reception Threshold Test; D013997:Time Factors