title: Assessing the efficacy of hearing-aid amplification using a phoneme test.
abstract: Consonant-vowel (CV) perception experiments provide valuable insights into how humans process speech. Here, two CV identification experiments were conducted in a group of hearing-impaired (HI) listeners, using 14 consonants followed by the vowel /ɑ/. The CVs were presented in quiet and with added speech-shaped noise at signal-to-noise ratios of 0, 6, and 12 dB. The HI listeners were provided with two different amplification schemes for the CVs. In the first experiment, a frequency-independent amplification (flat-gain) was provided and the CVs were presented at the most-comfortable loudness level. In the second experiment, a frequency-dependent prescriptive gain was provided. The CV identification results showed that, while the average recognition error score obtained with the frequency-dependent amplification was lower than that obtained with the flat-gain, the main confusions made by the listeners on a token basis remained the same in a majority of the cases. An entropy measure and an angular distance measure were proposed to assess the highly individual effects of the frequency-dependent gain on the consonant confusions in the HI listeners. The results suggest that the proposed measures, in combination with a well-controlled phoneme speech test, may be used to assess the impact of hearing-aid signal processing on speech intelligibility.
authors.affiliation: Hearing Systems Group, Department of Electrical Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.
authors.forename: Christoph
authors.initials: C
authors.lastname: Scheidiger
authors.affiliation: Beckman Institute, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801, USA.
authors.forename: Jont B
authors.initials: JB
authors.lastname: Allen
authors.affiliation: Hearing Systems Group, Department of Electrical Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.
authors.forename: Torsten
authors.initials: T
authors.lastname: Dau
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000368:Aged; D001302:Audiometry, Speech / Q000379:methods*; D004558:Electric Stimulation; D004867:Equipment Design; D006310:Hearing Aids; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000523:psychology / Q000534:rehabilitation*; D006801:Humans; D009622:Noise / Q000009:adverse effects; D010470:Perceptual Masking; D019986:Persons with Hearing Disabilities / Q000523:psychology / Q000534:rehabilitation*; D010700:Phonetics; D011237:Predictive Value of Tests; D021641:Recognition, Psychology; D012815:Signal Processing, Computer-Assisted; D013061:Speech Acoustics; D013065:Speech Intelligibility; D013067:Speech Perception; D014833:Voice Quality