TEAS: Exploiting Spiking Activity for Temporal-wise Adaptive Spiking Neural Networks

Spiking neural networks (SNNs) are energy-efficient alternatives to commonly used deep artificial neural networks (ANNs). However, their sequential computation pattern over multiple time steps makes processing latency a significant hindrance to deployment. In existing SNNs deployed on time-driven hardware, all layers generate and receive spikes in a synchronized manner, forcing them to share the same time steps. This often leads to considerable time redundancy in the spike sequences and considerable repetitive processing. Motivated by the effectiveness of dynamic neural networks for boosting efficiency, we propose a temporal-wise adaptive SNN, namely TEAS, in which each layer is configured with independent number of time steps to fully exploit the potential of SNNs. Specifically, given an SNN, the number of time steps of each layer is configured according to its contribution to the final performance of the whole network. Then, we exploit the temporal transforming module to produce a dynamic policy that can adapt the temporal information dynamically during inference. The adaptive configuration generating process enables trade-offs between model complexity and accuracy. Through extensive experiments on challenging datasets, we demonstrate that TEAS significantly improves energy efficiency and processing latency while achieving comparable accuracy to state-of-the-art methods.