A signal-to-noise ratio model for the speech-reception threshold of the hearing impaired.
This paper reviews the results of a series of investigations inspired by a model of the speech-reception threshold (SRT) of hearing-impaired listeners. The model contains two parameters accounting for the SRT of normal-hearing listeners (SRT in quiet and signal-to-noise ratio corresponding to the threshold at high noise levels), two parameters describing the hearing loss (attenuation and threshold elevation in terms of signal-to-noise ratio), and three parameters describing the hearing aid (acoustic gain, threshold elevation expressed in signal-to-noise ratio, and equivalent internal noise level). Experimental data are reported for three different types of hearing impairment: presbycusis, hearing losses with a pathological origin, and noise-induced losses. The model gives an excellent description of the data. It demonstrates that for many hearing-impaired persons speech intelligibility at noise levels beyond 50 to 60 dB(A) is their main problem, whereas hearing aids are most effective below that noise level.
D001309:Auditory Threshold; D006310:Hearing Aids; D006317:Hearing Loss, Noise-Induced / Q000175:diagnosis; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D010470:Perceptual Masking; D011304:Presbycusis / Q000175:diagnosis; D011571:Psychoacoustics; D013063:Speech Discrimination Tests / Q000379:methods*; D013069:Speech Reception Threshold Test / Q000379:methods*