Consistency of polychronous neural group activation supports a role as an underlying mechanism for representation and memory: detailed methods and results

Izhikevich (2006a) has proposed that certain strongly connected groups of neurons known as polychronous neural groups (or PNGs) might provide the neural basis for representation and memory. Polychronous groups exist in large numbers within the connection graph of a spiking neural network, providing a large repertoire of structures that can potentially match an external stimulus (Izhikevich, 2006a; Izhikevich et al., 2004). In this paper we examine some of the requirements of a representational system and test the idea of PNGs as the underlying mechanism against one of these requirements, the requirement for consistency in the neural response to stimuli. The results provide preliminary evidence for consistency of PNG activation in response to known stimuli, although these results are limited by problems with the current methods for detecting PNG activation.