Laboratory for Dynamics of Emergent Intelligence
Laboratory Head
Yoko YAMAGUCHI (Ph.D.)
The important property of brain-style intelligence is the ability to adopt the ever-changing environments based on real-time computation of contextual information including external stimuli and internal memory. We hypothesize that such flexibility can emerge because of dynamical linking among neural assemblies based on synchronization of neural activity oscillations. Our research aim is to elucidate computational theory on the emergent property of brain-style intelligence based on dynamical linking hypothesis. We use theoretical studies, computer experiments, noninvasive human brain activity measurements(EEG, fMRI, TMS), and also engineering approach (robotics). This year we developed our computational theory of rat hippocampal memory formation based on theta phase precession to include "grid cells" in the entorhinal cortex. The entorhinal grid cells can be generated based on a simple self-motion integration and lead place cells through projection to the hippocampus by using theta phase coding of theta phase precession. Among our studies on human brain activity, we reported EEG activities of Japanese Chess (Shogi) players representing expertise. The specific activities appear instantaneously after the piece pattern display distinguishing good and bad shapes of piece alignment. This result allows us to enter further studies of intuitive thought typical in shogi players. As analyses of ongoing activities in the brain such as noises and oscillations, we proposed a new illusion pattern where intrinsic activities of orientation columns in the visual cortex may take essential role. Furthermore, TMS experiment system was established to demonstrate causal roles of synchronization in human cognitive functions.
- Memory formation by theta phase coding in the hippocampus
- Human episodic memory, experiments and model studies
- Measurements of dynamical linking of human brain activities in mental tasks (EEG, Eye mobement, fMR,,TMS)
- Computational theories of thinking based on theories of brain dynamics and robotics experiments
- Neural Mechanisms of Intuitive thought in SHOGI (Japanese chess)
- November 23, 2008
- Intuitive thinking of professional Shogi-players' was clarified to originate from 'intuitive circuits' grown due to long term brain training
- Sato, N., Ozaki, T.J., et al.:
"Subsequent memory-dependent EEG theta correlates to parahippocampal blood oxygenation level-dependent response."
Neuroreport 21:168-172 (2010) - Sato, N. and Yamaguchi, Y.:
"A Computational Predictor of Human Episodic Memory Based on a Theta Phase Precession Network."
PLoS ONEe7536-1 - 9 (2009) - Nakano, T., et al.:
"Synchronization of spontaneous eyeblinks while viewing video stories."
Proceedings of the Royal Society B 276: 3635-3644 (2009) - Colliaux, D., Molter, C., and Yamaguchi, Y.:
"Working memory dynamics and spontaneous activity in a flip-flop oscillations network model with the Milnor attractor."
Cogn. Neurodyn. 3: 141-151 (2009) - Yamaguchi, Y.:
"The Brain Computation Based on Synchronization of Nonlinear Oscillations: On Theta Rhythms in Rat Hippocampus and Human Scalp EEG."
Lect. Notes Comput. Sci. 5286: 1-12 (2008). - Molter, C. and Yamaguchi, Y.:
"Entorhinal theta phase precession sculpts dentate gyrus place fields."
Hippocampus 18:919-30 (2008). - Kitajo, K., Doesburg, SM., Yamanaka, K., Nozaki, D., Ward, LM., and Yamamoto, Y.:
"Noise-induced large-scale phase synchronization of human brain activity associated with behavioural stochastic resonance."
Europhys. Lett. 80:40009-1-40009-6 (2007). - Mizuhara, H. and Yamaguchi, Y.:
"Human cortical circuits for central executive function emerge by theta phase synchronization."
NeuroImage 36: 232-244 (2007). - Yamaguchi, Y., Sato, N., Wagatsuma, H., Wu, Z., Molter, C., and Aota, Y.:
"A unified view of theta-phase coding in the entorhinal-hippocampal system."
Curr. Opin. Neurobiol. 17:197-204(2007). - Miwakeichi, F., Montes-Martivez, E., Valdes-Sosa, P., Nishiyama, N., Mizuhara, H., and Yamaguchi, Y.:
"Decomposing EEG data into space-time-frequency components using parallel factor analysis."
NeuroImage 22:1035-1045 (2004).