title: Evaluation of prosodic and segmental change in speech-modulated bone-conducted ultrasound by mismatch fields.
abstract: Speech-modulated bone-conducted ultrasound (BCU) can transmit speech sounds for some profoundly deaf individuals. Hearing aids using BCU are considered to be a novel hearing system for such individuals. In our previous study, the speech discrimination for speech-modulated BCU was objectively confirmed using a magnetoencephalography. Moreover, in our previous behavioral study, prosodic information for speech-modulated BCU could also be discriminated in the normal hearing. However, the prosodic discrimination for speech-modulated BCU has not objectively been studied. In order to evaluate the prosodic discrimination for speech-modulated BCU, mismatch fields (MMFs) elicited by prosodic and segmental change were measured for speech-modulated BCU and air-conducted speech. Ten Japanese participants with normal hearing took part in this study. Stimuli re-synthesized from the speech of a native Japanese female adult were used. Standard stimulus was /itta/ with a flat pitch pattern, and two deviant stimuli were /itta?/ with a rising pitch pattern and /itte/ with a flat pitch pattern. All and nine participants elicited the prominent MMF elicited by the prosodic and segmental change for the speech-modulated BCU, respectively. The moment of MMF components for speech-modulated BCU was significantly smaller than those for air-conducted speech, while no difference in the MMF latency elicited by the prosodic and segmental change were observed between both stimulus conditions. Comparing the MMFs elicited by prosodic and segmental change, no significant differences were observed for both stimulus conditions. Thus, it is suggested that the prosodic change can be discriminate to the same degree as segmental change even for speech-modulated BCU. However, discrimination capability for speech-modulated BCU is slightly inferior to that for air-conducted speech.
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan; Nissay Hospital, 6-3-8 Itachibori Nishi-ku, Osaka 550-0012, Japan. Electronic address: tokayasu@naramed-u.ac.jp.
authors: Tadao
authors: T
authors: Okayasu
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. Electronic address: t-nishim@naramed-u.ac.jp.
authors: Tadashi
authors: T
authors: Nishimura
authors: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan. Electronic address: s-nakagawa@aist.go.jp.
authors: Seiji
authors: S
authors: Nakagawa
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. Electronic address: akinori@naramed-u.ac.jp.
authors: Akinori
authors: A
authors: Yamashita
authors: Department of Electronic Engineering, Kobe City College of Technology, 8-3 Gakuenhigashicho, Nishi-ku, Kobe, Hyogo 651-2194, Japan. Electronic address: nagatani@kobe-kosen.ac.jp.
authors: Yoshiki
authors: Y
authors: Nagatani
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. Electronic address: ysd811yk@yahoo.co.jp.
authors: Yuka
authors: Y
authors: Uratani
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. Electronic address: toshya@naramed-u.ac.jp.
authors: Toshiaki
authors: T
authors: Yamanaka
authors: Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. Electronic address: hosoi@naramed-u.ac.jp.
authors: Hiroshi
authors: H
authors: Hosoi
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods* / Q000592:standards; D000328:Adult; D001844:Bone Conduction / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D010700:Phonetics; D013060:Speech / Q000502:physiology*; D055815:Young Adult
keywords: ANOVA; BCU; Bone-conducted ultrasound; ECD; MEG; MMF; Mismatch field; Prosody; SL; Ultrasonic perception; analysis of variance; bone-conducted ultrasound; equivalent current dipole; magnetoencephalography; mismatch field; sensation level