S2TE: Staged Scale-Free Topology Evolution for Sparse Spiking Neural Networks
摘要
Spiking Neural Networks (SNNs) represent a promising paradigm for energy-efficient machine learning. However, achieving high performance under significant sparsity constraints remains challenging. In this work, we present Staged Scale-Free Topology Evolution (S2TE), a novel sparse training framework for SNNs that systematically combines layer-wise scale-free topology initialization with a conceptually inspired, three-stage weight pruning and regeneration process comprising exploratory growth, topology refinement, and stability maintenance. S2TE uses the Barabási-Albert model to establish sparse layer-wise scale-free topologies from the outset, and the staged dynamic topology optimization approach enables efficient balance between structural exploration and exploitation. Experiments on CIFAR10, CIFAR100, and DVS-CIFAR10 benchmarks show that S2TE-trained SNNs achieve competitive accuracy while maintaining merely 30% connectivity. The resulting networks exhibit layer-wise scale-free-like connectivity, which is associated with efficient and robust information flow in the evaluated benchmarks. These findings demonstrate the promise of staged topology evolution for improving sparse SNN training and motivate further study in broader scenarios.