A Different Approach to the Noise Problem of the Hearing Impaired

Hearing aid design to alleviate the noise problem has concentrated on improving the signal-to-noise ratio with the aid, using devices such as directional microphones, adaptive filters, and circuits that discriminate between steady-state noise and speech. The design approach discussed here is directed at improving the speech recognition of hearing-impaired listeners at a given signal-to-noise ratio, by restoring to their perception speech cues they no longer hear because of their impairment. This allows them to retain more of the redundant information in speech after masking has taken its toll, and empowers their ability to separate desired from undesired signals (what Broadbent calls "selective listening" in persons with normal hearing). Experimental results are presented.