Study of intelligibility for practical application of bone-conducted ultrasonic hearing aids

• Project/Area Number: 23791923
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Otorhinolaryngology
• Research Institution: Nara Medical University
• Principal Investigator: YAMASHITA Akinori 奈良県立医科大学, 医学部, 助教 (50588522)
• Project Period (FY): 2011-04-28 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2013: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2012: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2011: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 骨導超音波 / 補聴器 / 語音 / 超音波 / 骨導 / 弁別能

Outline of Final Research Achievements

We investigated the ability to recognize speech delivered by bone-conducted ultrasound (BCU) to develop bone-conducted ultrasonic hearing aids (BCUHA). Three individuals with normal hearings could not perceive any speech information from ultrasonic signals among 34 tests. The average dynamic range was 18.1 ± 3.2 dBSL. This finding is consistent with previous reports. A comparison of speech discrimination tests of bone-conducted ultrasound in individuals of different ages found that the tests for BCU were less intelligible in older persons. This finding supported the hypothesis that BCU can be perceived in the cochlear basal turn. In addition,　we examined the effects of rehabilitation in individuals with normal hearing. The intelligibility of the speech discrimination test with BCU was inconsistent in the hearing-impaired.
Our findings provide important clues for the development of BCUHA. The perception mechanisms of BCU should be fully elucidated in future studies.

Research Products

• [Journal Article] Residual inhibition of tinnitus induced 30-kHz bone-conducted ultrasound (2014)
  • Author(s): Toshizo Koizumi, Tadashi Nishimura, Akinori Yamashita, Toshiaki Yamanaka, Tomoaki Imamura, Hiroshi Hosoi
  • Journal Title: Hearing Reserch Volume: 310 Pages: 48-53
  • Peer Reviewed
• [Journal Article] An Examination of effects of broadband aie-conducted masker on the speech intelligibility of speech-modulated bone-conduction ultrasound (2014)
  • Author(s): Tadashi Nishimura, Tadao Okayasu, Osamu Saito, Ryota Shimokura, Akinori Yamashita, Toshiaki Yamanaka, Tadashi Ktahara
  • Journal Title: Hearing Reserch Volume: 317 Pages: 41-49
  • Peer Reviewed
• [Journal Article] Evaluation of prosodic and segmental change in speech-modulated bone-conducted ultrasound by mismatch fields (2014)
  • Author(s): Tadao Okayasu,Tadashi Nishimura,Seiji Nakagawa, Akinori Yamashita, Yoshiki Nagatani, Yuka Uratani, Toshiaki Yamanaka, Hiroshi Hosoi
  • Journal Title: Neuroscience Letters Volume: 559 Pages: 117-121
  • Peer Reviewed
• [Journal Article] Human Ultrasonic hearing is induced by a direct ultrasonic stimulation of the cochlea (2013)
  • Author(s): Tadao Okayasu、Tadashi Nishimura、Akinori Yamashita、Osamu Saito、 Shuichi Yanai、Hiroshi Hosoi
  • Journal Title: Neuroscience Letters Volume: 539 Pages: 71-76
  • Peer Reviewed
• [Presentation] 骨導超音波のtemporal window of integrationについて (2014)
  • Author(s): 岡安唯、浦谷悠加、西村忠己、中川誠司、山下哲範、細井裕司、北原糺
  • Organizer: 日本聴覚医学会
  • Place of Presentation: 海峡メッセ下関
  • Year and Date: 2014-11-27 – 2014-11-28
• [Presentation] 耳鳴の治療・薬物療法から音響療法まで (2014)
  • Author(s): 山下哲範、北原糺
  • Organizer: 日本音響学会
  • Place of Presentation: 北海学園大学（札幌）
  • Year and Date: 2014-09-03 – 2014-09-05
  • Invited
• [Presentation] The Difference Betwee Bone-Conducted Ultrasound and Audible Sound in Japanese Monosyllable (2014)
  • Author(s): Akinori Yamashita,Tadao Okayasu ,Tadashi Nishimura, Yoshiki Nagatani, Hiroshi Hosoi
  • Organizer: 37th ARO MIDWINTER MEETING
  • Place of Presentation: San Diego
• [Presentation] DIFFERENCE FOR BONE-CONDUCTED ULTRASOUND AND AIR-CONDUCTED SUDIBLE SOUND IN SEECH RECOGNITION (2013)
  • Author(s): Akinori Yamashita, Tadao Okayasu ,Tadashi Nishimura, Hiroshi Hosoi
  • Organizer: 20th IFOS World Congress
  • Place of Presentation: Seoul
• [Presentation] The Effect of Visual Information on intelligibility in Bone-onducted Ultrasound Perception (2013)
  • Author(s): Akinori Yamashita, Tadashi Nishimura, Yoshiki Nagatani, Hiroshi Hosoi
  • Organizer: 36th ARO MIDWINTER MEETING
  • Place of Presentation: Baltimore marriotto Waterfront hotel
• [Presentation] 岡安 唯、中川 誠司、 西村 忠己、 山下 哲範、 吉田 悠加、 細井 裕司 (2012)
  • Author(s): 刺激の周波数構造が聴覚野の時間積分に与える影響について
  • Organizer: 第57回 日本聴覚医学会学術総会
  • Place of Presentation: 国立京都国際会館
• [Presentation] 骨導超音波のプロソディーの変化に対するミスマッチ反応 (2011)
  • Author(s): 岡安唯、西村忠己、山下哲範、中川誠司、吉田悠加、柳井修一、長谷芳樹、細井祐司
  • Organizer: 日本聴覚医学会
  • Place of Presentation: アクロス福岡