title: Effects of the simultaneous application of nonlinear frequency compression and dichotic hearing on the speech recognition of severely hearing-impaired subjects: simulation test.
abstract: OBJECTIVE
  The clinical effects of the simultaneous application of nonlinear frequency compression and dichotic hearing on people with hearing impairments have not been evaluated previously. In this study, the clinical effects of the simultaneous application of these two techniques on the recognition of consonant-vowel-consonant (CVC) words with fricatives were evaluated using normal-hearing subjects and a hearing loss simulator operated in the severe hearing loss setting.
  
  
  METHODS
  A total of 21 normal-hearing volunteers whose native language was English were recruited for this study, and two different hearing loss simulators, which were configured for severe hearing loss in the high-frequency range, were utilized. The subjects heard 82 English CVC words, and the word recognition score and response time were measured.
  
  
  RESULTS
  The experimental results demonstrated that the simultaneous application of these two techniques showed almost even performance compared to the sole application of nonlinear frequency compression in a severe hearing loss setting.
  
  
  CONCLUSIONS
  Though it is generally accepted that dichotic hearing can decrease the spectral masking thresholds of an hearing-impaired person, simultaneous application of the nonlinear frequency compression and dichotic hearing techniques did not significantly improve the recognition of words with fricatives compared to the sole application of nonlinear frequency compression in a severe hearing loss setting.
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Jong Ho
authors.initials: JH
authors.lastname: Hwang
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Kyoung Won
authors.initials: KW
authors.lastname: Nam
authors.affiliation: Institute of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Yoon
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Jinryoul
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Sunhyun
authors.initials: S
authors.lastname: Yook
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Samsung Medical Center, Seoul, Korea.
authors.forename: Sung Hwa
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Dong Pyo
authors.initials: DP
authors.lastname: Jang
authors.affiliation: Department of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: In Young
authors.initials: IY
authors.lastname: Kim
keywords: Dichotic Listening Tests; Hearing Loss; Signal Processing, Computer-Assisted