HM-DF SNN: Transcending Conventional Online Learning with Advanced Training and Deployment

Spiking Neural Networks (SNNs) are considered to have enormous potential in the future development of Artificial Intelligence due to their brain-inspired and energy-efficient properties. Compared to vanilla Spatial-Temporal Back-propagation (STBP) training methods, online training can effectively overcome the risk of GPU memory explosion. However, current online learning framework cannot tackle the inseparability problem of temporal dependent gradients and merely aim to optimize the training memory, resulting in no performance advantages compared to the STBP training models in the inference phase. To address the aforementioned challenges, we propose Hybrid Mechanism-Driven Firing (HM-DF) model, which is a family of advanced models that respectively adopt different spiking calculation schemes in the upper-region and lower-region of the firing threshold. We point out that HM-DF model can effectively separate temporal gradients and tackle the mismatch problem of surrogate gradients, as well as achieving full-stage optimization towards computation speed and memory footprint. Experimental results have demonstrated that HM-DF model can be flexibly combined with various techniques to achieve state-of-the-art performance in the field of online learning, without triggering further power consumption.