Postdoc: Saeka Tomatsu

Saeka Tomatsu

Career Summary

2000-2002 Earned a master`s degree. Graduate School of Humanities and Sciences, Nara Women`s University
2002-2005 Earned a doctoral degree. Graduate School of Arts and Sciences, The University of Tokyo
2005-2010 Flexible researcher of Tokyo Metropolitan Institute for Neurosience
2010-2011 Visiting researcher of Tokyo Metropolitan Institute for Neurosience,
2011 Part-time researcher of Tokyo Metropolitan Institute of Medical Science
2011.10- Present: Department of Neurophysiology, NCNP

Research Theme

Since our birth, we use instinctively our body to explore the world around us. As we grow and our our limbs become more skillful, we aimed not only for gross movements, but we start to use our extremities to perform faster, better and more beautiful voluntary movements. During movement, instinctive program and intentional control are essential, by working apart or together, adjusting our movement, according to the environment and the position of the body. My research is aimed to elucidate how the central nervous system (CNS) chooses and unite redundant mechanisms to generate voluntary movements. Previously, I was focused on the functional relation between the cerebrum and the cerebellum to control limb movement. It has been said that the "cerebrum" can process information efficiently by cooperating with the "cerebellum". As for the cooperation between the cerebrum and the cerebellam studies of eye movements have been progressing. Besides, it has been found that movements of the hand and the foot, and mental function also go smoothly because of the cooperative mechanism between the cerebrum and the cerebellum. Therefore, the cerebellum must be a key in using smoothly each strong point of movements which have several origins. Nowadays, I have shifted my research focus to the spinal cord and its connections to the brain and muscles. It is known that the spinal cord transmits the motor program from the brain to the muscles and conversely, transmits the information from the extremities to the brain. On the other hand, several studies have shown that neural circuits in the spinal cord store the greatest part of the instinctive motor program. Although the spinal cord was consider the only "Information conduction pathways", seems that additional steps for information processing and storage can’t be explained by this model. So, there may be a mechanism that selects and combines effectively the instinctive and volitional motor programs which are stored in the spinal cord and motor related areas in the brain, respectively. I will continue exploring the central nervous system mechanisms which enable us to move our own body smoothly, by combining different techniques as direct recording of neural activity, fMRI and psychophysical experiments.


  • Lee J, Kagamihara Y, Tomatsu S, and Kakei S.  The functional role of the cerebellum in visually guided tracking movement.  Cerebellum, 2012, 11(2):426-433.
  • Tomatsu S,Someya Y, Sung YW, Ogawa S, and Kakei S.  Temporal feature of BOLD responses varies with temporal patterns of movement. Neurosci Res, 2008, 62(3):160-167.
  • Tomatsu S and Ohtsuki T.  The effect of visual transformation on bimanual circling movement. Exp Brain Res, 2005, 166(2): 277-286.

Research Grants

  • JFY2008-2009 Grants-in-Aid for Scientific Research(for young scientists)
  • JFY2006-2007 Grants-in-Aid for Scientific Research(for young scientists)

Self Introduction

I have thought various things since I was a child, like "Is my Red the same as other people`s red ?"  "Why the carrot I ate is taken into my body through the intestine ?" I was impressed learning the mechanism at science class.Even though I know the existence of small material that I can`t see, science can`t explain the "mind", which remains a mystery to me. Perhaps I have kept my life as such until today. Although I am a mother with one child, I feel I can`t be an adult yet.