Evolution of a Circuit of Spiking Neurons for Phototaxis in a Braitenberg Vehicle

Abstract

Animal nervous systems have evolved to use spiking neurons but the 'artificial nervous systems' of animats typically are designed, not evolved, and use networks of formal, artificial neurons. We describe the evolution of circuits of spiking neurons for a robot, motivated by the desire to study links between neurophysiology and behaviour in artificial and (ultimately) natural animals. Spiking neurons have computational capabilities additional to those of artificial neurons based on activation functions. In particular, they should be better suited to processing temporal sequences. Thus, we describe early work aimed at evolution of neural circuitry which, when implanted in a Braitenberg type 2b vehicle, promotes phototaxis behaviour in the form of movement towards flashing lights of a particular frequency. The longer-term aim is to evolve natural taxis behaviours such as that observed in the cricket.