Simulation study on functional roles of morphological strucutre of neurons in cerebellar learning

• Project/Area Number: 17K07049
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurophysiology / General neuroscience
• Research Institution: The University of Electro-Communications
• Principal Investigator: Yamazaki Tadashi 電気通信大学, 大学院情報理工学研究科, 准教授 (40392162)
• Co-Investigator(Kenkyū-buntansha): 五十嵐 潤 国立研究開発法人理化学研究所, 情報システム本部, 上級研究員 (60452827)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2017: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
• Keywords: 小脳 / シミュレーション / スパイキングニューロン / マルチコンパートメント / 数値シミュレーション / マルチコンパートメントモデル / 並列計算 / GPU / 学習 / 細胞形状 / 計算論的神経科学 / 細胞形態 / 高性能神経計算

Outline of Final Research Achievements

Neurons have characterstic morphotogical structures, yet how the structures affect information processing in the brain remains unknown. In this study, we built a spiking network model of the cerebellar cortex composed of Purkinje cells, granule cells, and Golgi cells, that have detailed and realistic morphological shapes. We employed a graphics processing unit (GPU) for parallel computing and achieved 24 times faster numerical simulation than a standard CPU. The network exhibited synchronous oscillatory firing of granule cells and Golgi cells at around 14 Hz, whereas Purkinje cells also emitted spikes with the correlated firing rate. We found that when the dendrites of the Purkinje cells were shrinked, which was observed in animals with neuronal / genetic disorders, the synchronized firing among the Purkinje cells was disrupted. These results suggest that morphological structure of neurons play important roles in normal brain functions.

Academic Significance and Societal Importance of the Research Achievements

ニューロンの空間形状が脳の情報処理に及ぼす影響を解明するためには、実際に形状を変化させることが必要だが、それを実験的に行うことは極めて難しい。一方、計算機シミュレーションではそれは容易である。ニューロンの空間形状の変化は神経疾患・遺伝子疾患でしばしば見られる現象であり、そのような深刻な病気に何らかの影響を与えているはずである。本研究はそのような病気の原因解明に資するツールとして神経回路シミュレーションを提案するものである。

Research Products

• [Int'l Joint Research] University of Pavia(イタリア)
• [Presentation] Dendritic discrimination of temporal input sequences in cerebellar Purkinje cells (2019)
  • Author(s): Yuki Yamamoto, Tadashi Yamazaki
  • Organizer: Computational Neuroscience (CNS*2019)
  • Int'l Joint Research
• [Presentation] Large-scale simulation of the little brain (2019)
  • Author(s): Tadashi Yamazaki
  • Organizer: RIKEN Workshop on Neuromorphic Computing
  • Int'l Joint Research / Invited
• [Presentation] Parallel numerical simulation of a multicompartment network model of the cerebellum on GPU (2019)
  • Author(s): Taira Kobayashi, Tadashi Yamazaki
  • Organizer: 第29回日本神経回路学会全国大会
• [Presentation] Dendritic discrimination of temporal input sequences in cerebellar Purkinje cells (2019)
  • Author(s): Yuki Yamamoto, Tadashi Yamazaki
  • Organizer: Computational Neuroscience 2019 (CNS*2019)
  • Int'l Joint Research
• [Presentation] 小脳顆粒層のマルチコンパートメントモデルシミュレーション (2017)
  • Author(s): 露木 吏, 山本 祐輝, 山﨑 匡
  • Organizer: 第27 回日本神経回路学会全国大会
• [Presentation] Implementing synaptic plasticity on a cat-scale artificial cerebellum (2017)
  • Author(s): Tadashi Yamazaki, Wataru Furusho
  • Organizer: 第40回日本神経科学大会,
  • Int'l Joint Research
• [Presentation] Implementation of Learning Mechanisms on a Cat-scale Cerebellar Model and its Simulation (2017)
  • Author(s): Wataru Furusho, Tadashi Yamazaki
  • Organizer: 26th International Conference on Artificial Neural Networks (ICANN) 2017
  • Int'l Joint Research
• [Presentation] ヒト規模の脳神経回路シミュレーションを目指して: 小脳の場合 (2017)
  • Author(s): 山﨑 匡
  • Organizer: 科学技術計算分科会2017年度会合「拡がるHPC ～新たな鼓動～」
  • Invited