Effects of reducing low-frequency amplification on consonant perception in quiet and noise

The aim of this study was to assess the effect of low-frequency amplification on speech recognition performance by hearing-impaired listeners. Consonant identification performance by subjects with flat hearing losses and high-frequency hearing losses was assessed in three different hearing aid conditions, in quiet and noise. The experimental hearing aids all provided extra high-frequency amplification but differed in the amount of low-frequency amplification. The results showed that listeners with flat hearing losses benefited by low-frequency amplification, whereas subjects with high-frequency hearing losses exhibited deteriorating scores in conditions with greatest low-frequency amplification. Analyses of phonetic feature perception and individual consonant recognition scores revealed subtle interactions between hearing loss configuration and amplification contour.