A Spike-based Computer Architecture for Sensory Processing

University Of Florida, Gainesville FL

Investigators

Abstract

0541241 PI: John G. Harris University of Florida A Spike-Based Computer Architecture for Sensory Processing The PIs will develop, study, and build a neurobiologically inspired architecture based on neuronal spikes (or action potentials). The proposed architecture combines previous spike-based sensory processing ideas developed by the PIs with a compelling model of brain computation called the Liquid State Machine (LSM). This model provides a conceptual framework for working with biologically realistic pulsed neuron models (integrate-and-fire neurons) as the basic computational element within a recurrent nonlinear architecture. The PIs propose three key steps for developing networks of spiking processing elements that are useful for computation: 1. The PIs will develop a sampling theory for converting continuous variable inputs into aperiodic spike trains (and likewise transform spikes trains back to continuous amplitude signals). 2. Although interesting, the architecture of the LSM can be largely improved once the characteristics of the computation are better understood. In particular, while the interconnect of the liquid is arbitrary and fixed, the PIs plan to develop a theory of adaptation for such spike based representations. 3. The PIs will map the spike-based architecture to todays silicon electronics. This hybrid analog/digital architecture is fundamentally different from both conventional digital architectures and past analog computing devices. However, the proposed architecture will be of only scientific interest if it cannot be built with competitive performance measures in terms of computational capability, power consumption, noise immunity and dynamic range. Therefore, in order to design the architecture in silicon, the PIs will identify key computational principles, design signal transformations, and fabricate the resulting building blocks with huge numbers of sufficiently small components in CMOS technology. Finally, in order to ground the theoretical research and design in engineering practice, the PIs propose to develop a prototype system for chemical sensing using an off-the-shelf electronic nose (or e-nose) as the front end. This application was chosen due to its importance in homeland security, and also because it provides a natural input to the proposed spike-based architecture.