title: Biological basis of hearing-aid design.
abstract: We show that we can accurately model the auditory-nerve discharge patterns in response to sounds as complex as speech and ask how we may exploit this knowledge to test new strategies for hearing-aid signal processing. We describe the auditory-nerve representations of vowels in normal and noise-damaged ears. The normal representations are predicted well by a cochlear signal processing model originally developed by Carney (Carney, L. H. J. Acoust. Soc. Am. 93:401-417, 1993). Basilar-membrane tuning is represented by a time-varying narrow-band filter. Outer hair cell control of tuning is exerted by a nonlinear feedback path. We show that the effects of noise-induced outer hair cell damage can be modeled by scaling the feedback signal appropriately and use the model to test one strategy for hearing-aid speech processing. We conclude by discussing some aspects of future trends in biomedical engineering approaches to problems of hearing impairment.
authors.affiliation: Center for Hearing Sciences and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA. msachs@bme.jhu.edu
authors.forename: Murray B
authors.initials: MB
authors.lastname: Sachs
authors.forename: Ian C
authors.initials: IC
authors.lastname: Bruce
authors.forename: Roger L
authors.initials: RL
authors.lastname: Miller
authors.forename: Eric D
authors.initials: ED
authors.lastname: Young
mesh_terms: D000200:Action Potentials / Q000502:physiology; D003051:Cochlea / Q000294:innervation* / Q000503:physiopathology; D003056:Cochlear Nerve / Q000502:physiology* / Q000503:physiopathology; D003198:Computer Simulation; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005583:Fourier Analysis; D006309:Hearing / Q000502:physiology; D006310:Hearing Aids; D006311:Hearing Disorders / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D008959:Models, Neurological; D010700:Phonetics; D011474:Prosthesis Design / Q000379:methods; D012680:Sensitivity and Specificity; D013067:Speech Perception / Q000502:physiology*