Integrated pulse neuron circuit for asynchronous pulse neural networks

We propose an integrated neuron circuit for an asynchronous pulse neural network model. This circuit is suitable for an implementation of a wide range of spatio-temporal coding networks since the circuit can function as both a coincidence detector and an integrator of the input pulses by properly setting bias voltage. We fabricate a prototype chip for the proposed circuit using MOSIS HP/Agilient 0.5 /spl mu/m CMOS semiconductor process. The experimental measurements from the chip confirm that the integrated neuron circuit qualitatively replicates the behavior of the model. Especially, coincidence detection of input pulses in a short-time window, and further, complex behavior including chaos in the internal state value and in the interspike intervals of the output pulses are illustrated.

I. Introduction

Recently, an information processing hypothesis based on a fine spatio-temporal structure among action potential pulses in the brain has received a lot of attention. Some physiological experiments and theoretical researches have suggested that the brain utilizes a spatia-temporal coding [1], [2].