TR-H-0012 :1993.7.16

Yukio Hayashi

Oscillatory Neural Network and Learning of Continuously Transformed Patterns

Abstract:We investigate experimentally the dynamic behaviors of an oscillatory neural network. Computer simulations show an interesting characteristic: the autonomous generation of a limit cycle near a memory (memory retrieval with ambiguous fluctuation) for an input near a memory, and of a chaotic orbit among memories (autonomous search) for an input far from memories. We also analyze theoretically a few restricted behaviors near a memory. This type of neural network can treat spatiotemporal pattern processing in the brain. As an example of dynamic information processing, it is shown that continuously transformed pattern cycles for three Japanease characters are embedded in the limit cycles of the oscillatory neural network by a learning method. The existence in the brain of a continuously transformed. pattern operation for a character is also discussed from the cognitive psychological point of view. The characteristic behavior of limit cycle or chaos according to an input in our oscillatory neural network may be useful for developing a dynamic information processing mechanism for a spatiotemporal pattern in the brain.

Keywords: Oscillatory neural network, Dynamic information processing, Spatiotemporal pattern, Limit cycle near a memory, Chaotic orbit among memories, Continuous transformation, Learning of recurrent network