HISTORY . Summary of previous investigations.
Also the Laboratory was engaged in a pioneer work on developing numerical algorithms to investigate the bifurcations of steady states and limit cycles in nonlinear dynamical systems under parameter variation (small-scale approach with several main variables). These investigations showed that cooperative effects like physical phase-transitions and synchronization phenomena are normal to occur in biological neural networks despite a very chaotic spike activity of single neurons. In addition, metastable states of neural networks were proved to be useful to model short- term memory in a series of theoretical and simulation works . This led to development of a neural network model based on biologically plausible constraints on the elements of a network (similar to integrate-and-fire neurons ) which was capable of demonstrating metastable states.
This basic neural network model was used to model low frequency oscillations in the septum, the habituation in the hippocampus, metastable states in the cortex and the cerebellum.