Auditory filter nonlinearity in mild/moderate hearing impairment.
Sensorineural hearing loss has frequently been shown to result in a loss of frequency selectivity. Less is known about its effects on the level dependence of selectivity that is so prominent a feature of normal hearing. The aim of the present study is to characterize such changes in nonlinearity as manifested in the auditory filter shapes of listeners with mild/moderate hearing impairment. Notched-noise masked thresholds at 2 kHz were measured over a range of stimulus levels in hearing-impaired listeners with losses of 20-50 dB. Growth-of-masking functions for different notch widths are more parallel for hearing-impaired than for normal-hearing listeners, indicating a more linear filter. Level-dependent filter shapes estimated from the data show relatively little change in shape across level. The loss of nonlinearity is also evident in the input/output functions derived from the fitted filter shapes. Reductions in nonlinearity are clearly evident even in a listener with only 20-dB hearing loss.
Baker
Richard J
RJ
Human Communication and Deafness, School of Education, University Of Manchester, United Kingdom. richard.baker@man.ac.uk
Rosen
Stuart
S
D000161:Acoustic Stimulation; D000328:Adult; D001309:Auditory Threshold / Q000502:physiology*; D001489:Basilar Membrane / Q000503:physiopathology; D005260:Female; D018072:Hair Cells, Auditory, Outer / Q000503:physiopathology; D006316:Hearing Loss, High-Frequency / Q000175:diagnosis / Q000503:physiopathology; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis / Q000503:physiopathology; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008144:Loudness Perception / Q000502:physiology; D008297:Male; D008875:Middle Aged; D017711:Nonlinear Dynamics; D010470:Perceptual Masking / Q000502:physiology; D010897:Pitch Discrimination / Q000502:physiology; D013018:Sound Spectrography