Cortical activation patterns in relation to tempo discrimination; representation of time interval underlying the stream segregation

2016 Fiscal Year Final Research Report

• Project/Area Number: 26430034
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nerve anatomy/Neuropathology
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: OJIMA HISAYUKI 東京医科歯科大学, 大学院医歯学総合研究科, 非常勤講師(無給) (00104539)
• Research Collaborator: HAYASHI Koki 豊橋技術科学大学, 大学院工学研究科情報知能工学
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 一次聴覚野 / 時間表現 / 細胞活動 / テンポ / 繰返し音 / 膜電位感受性色素 / 識別学習 / モルモット

Outline of Final Research Achievements

The tempo or rhythm is an important time-related factor for determining the sound quality. We addressed questions as to animal's perceptual abilities of tempos and cortical activation patterns to sounds with different tempos.
Guinea pigs could discriminate between sounds with repeats of a segment (100ms long) at the interval-segment interval (ISI) of 1100 ms and at the ISI of 230 (or 110) ms (short-ISI), but not between the 1100 ms ISI and the much longer ISIs. In naive animals, these repeated sounds evoked AI activation (CA) only at the early 1st-2nd/3rd segments but very little at later segments for the short-ISI, while every segment was effective in evoking CA for the 1100 ms-ISI. Conditioning animals to the 1100-ms ISI changed the responsiveness to individual sound segments. Three/four-week training made later segments effective in evoking CA for the short-ISIs, while the same training increased the magnitude of CA evoked by the later segments for the longer 1100-ms ISI sound.

Free Research Field

聴覚皮質／神経科学