A comparison of the effects of hearing impairment and acoustic filtering on consonant recognition

The relationship between consonant recognition under conditions of acoustic filtering and hearing loss was studied in subjects with unilateral bearing impairments. Using a procedure involving suprathreshold loudness balance between ears, a spectrum shaper was used to match the (suprathreshold) audiometric configuration of the impaired ear. Consonant recognition data were obtained from the impaired ear and from the normal ear listening through the spectrum shaper. To the extent that consonant recognition was similar in the two ears, the effect of the patient's hearing impairment on phoneme identification could be related to the audiometric configuration. A comparison between consonant recognition scores for the impaired ears and for the ears listening through the spectrum shaper revealed large individual differences among subjects. Mean consonant recognition ability, however, was generally lower in the impaired ear. Although overall consonant recognition and the error probabilities for individual consonants tended to be different between ears, the patterns of feature recognition were quite similar.