Neural substrates underlying decision making based on free will

• Project/Area Number: 21800014
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Neuroscience in general
• Research Institution: The University of Tokyo
• Principal Investigator: UMEDA Kazumasa The University of Tokyo, 大学院・医学系研究科, 助教 (50548518)
• Project Period (FY): 2009 – 2010
• Project Status: Completed (Fiscal Year 2010)
• Budget Amount: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000); Fiscal Year 2010: ¥1,209,000 (Direct Cost: ¥930,000、Indirect Cost: ¥279,000); Fiscal Year 2009: ¥1,391,000 (Direct Cost: ¥1,070,000、Indirect Cost: ¥321,000)
• Keywords: 認知神経科学 / 脳波 / 経頭蓋時期刺激 / 意思決定 / 経頭蓋磁気刺激 / 自由意志

Research Abstract

The brain has an ability to access to various processing in the brain and to manipulate it in top-down manner. The ability of human being is overwhelming relative to the other animals both in quantitative and qualitative aspects. I hypothesized an existence of 'free will' and studied how top-down signals come into effect in the process of decision making. I applied transcranial magnetic stimulation (TMS) over the human prefrontal cortex and evaluated dynamics of effective connectivity from the prefrontal cortex. We found a change in TMS-EP dependent of task difficulty and behavioral performance. The results suggest that the efficiency of signal transmission from the prefrontal cortex changes dynamically depending on the strength of bottom-up signals.

Research Products

• [Presentation] Dynamical change in attentional signals from the frontal eye field dependent of visual saliency (2010)
  • Author(s): K.Umeda, Y.Morishima, V.Rajeswaren, K.Sakai
  • Organizer: 40^<th> Annual Meeting of Society for Neuroscience
  • Place of Presentation: サンディエゴコンベンションセンター(北米,カリフォルニア州)
  • Year and Date: 2010-11-16
• [Presentation] Dynamical change in attentional signals from the frontal eye field dependent of visual saliency (2010)
  • Author(s): 梅田和昌
  • Organizer: 北米神経科学学会第40回大会
  • Place of Presentation: サンディエゴコンベンションセンター(U.S.A. カリフォルニア州)
  • Year and Date: 2010-11-16
• [Presentation] Visual-saliency dependent changes in top-down signals from the frontal eye field (2010)
  • Author(s): K.Umeda, Y.Morishima, V.Rajeswaren, K.Sakai
  • Organizer: 第33回日本神経科学大会・第53回日本神経化学会大会・第20回日本神経回路学会大会合同大会
  • Place of Presentation: 神戸国際展示場(兵庫県)
  • Year and Date: 2010-09-03
• [Presentation] 視覚刺激の顕著さに依存した前頭眼野からのトップダウン信号の変化 (2010)
  • Author(s): 梅田和昌
  • Organizer: 日本神経科学学会第33回大会
  • Place of Presentation: 神戸コンベンションセンター(兵庫県 神戸市)
  • Year and Date: 2010-09-03
• [Presentation] Visual-saliency dependent changes in top-down signals from prefrontal cortex (2010)
  • Author(s): K.Umeda, V.Rajeswaren, Y.Morishima, K.Sakai
  • Organizer: 東京大学グローバルCOE「疾患のケミカルバイオロジー教育研究拠点」第2回リトリート・国際シンポジウム
  • Place of Presentation: 大磯プリンスホテル(神奈川県)
  • Year and Date: 2010-02-13
• [Presentation] Temporal dynamics of effective connectivity from frontal eye field (2010)
  • Author(s): K.Umeda, V.Rajeswaren, Y.Morishima, K.Sakai
  • Organizer: 脳と心のメカニズム 第10回 冬のワークショップ
  • Place of Presentation: ルスツリゾート(北海道)
  • Year and Date: 2010-01-13
• [Presentation] Dynamics of Functional Connectivity from Frontal Eye Field (2009)
  • Author(s): K.Umeda, V.Rajeswaren, Y.Morishima, K.Sakai
  • Organizer: 特定領域研究「統合脳」 平成21年度合同領域班会議
  • Place of Presentation: 一ツ橋学術総合センター(東京都)
  • Year and Date: 2009-12-19
• [Presentation] Dynamics of Functional Connectivity from Frontal Eye Field (2009)
  • Author(s): 梅田和昌
  • Organizer: 特定領域研究「統合脳」平成21年度 合同領域班会議
  • Place of Presentation: 一ツ橋学術総合センター(東京都)
  • Year and Date: 2009-12-19