Hearing impairment degrades signal-to-noise tolerance more than quiet speech perception.

Evidence

Communication situations involving background noise or reverberation often cause problems for the hearing impaired. An individual with impaired hearing might struggle in these kinds of situations even though speech intelligibility in quiet situations is normal. The hearing impaired often need a higher SNR to achieve the same speech intelligibility as normally hearing individuals. Plain amplification amplifies both the desired signal and the unwanted noise, and therefore it does not solve the problem of degraded speech intelligibility in the presence of background noise. Thus, several approaches have been developed to increase the SNR in the hearing aid output and so enhance the intelligibility in acoustically complex environments. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 2739

Categorization

• XREF: Directly bears on the SNR / cocktail-party hearing literature; also connects to spatial hearing and binaural unmasking topics in earlier chapters of this book.