B02 Modeling of ultra-adaptive to body change

Research Outline

Yasuharu KOIKE

Our group aims at the modeling of the mechanism underlying the recovery of the motor function after the alteration of the body, especially from the viewpoint of the reconstruction of a neural structure in hyper-adaptability. For conquering a drastic alteration of the body due to re-connection of muscles (such as an experiment in A02 group using monkey), neural system changes their process drastically by iterative optimization and learning of the controller. Several human and animal experiments have shown that such a drastic change of the neural system includes discontinuous change of the neural structure by a re-organization of muscle synergy. The re-organization is supposed to occur autonomously during the learning and optimization process.

In order to understand this process, our group constructs a mathematical model using (1) virtual surgery, (2) brain decoding, and (3) muscular-skeletal simulation. (1) “virtual surgery” realizes the transformation of the musculo-skeletal model, and causes the changes of the motion on a computer display. The direction of force on the display slowly changes from the force of the subjects, through the calculation of the muscle-force relationship on the muscular-skeletal model. Then, the brain’s adaptation process to the slow and continuous change of the virtual body is analyzed. (2) motion-EMG-EEG data obtained from the experiment of muscle re-connection in the virtual surgery and the real surgery of monkeys (in A02) are analyzed. (3) muscular-skeletal model of the monkey is realized on a dynamical simulator and the effect of the re-connection of the muscles is simulated. In order to recover the motion on the simulator, machine learning and optimization on the controller are performed. By discussing the learning process desired for recovery, and comparing them with the characteristics of the neural system found in the brain decoding, the mechanism of the reorganization of neural structure for body alteration is investigated.


Principal investigator Yasuharu KOIKE Professor, Tokyo Institute of Technology
Funded co-investigator Tetsuro FUNATO Associate Professor, The University of Electro-Communications
Co-investigators Natsue YOSHIMURA Associate Professor, Tokyo Institute of Technology
Dai YANAGIHARA Professor, The University of Tokyo
Shinya AOI Lecturer, Kyoto University
Kazuo TSUCHIYA Emeritus Professor, Kyoto University
Soichiro FUJIKI Assistant Professor, Dokkyo Medical University