🤖 AI Summary
Existing spiking neural networks (SNNs) are predominantly unimodal, limiting effective audio-visual cross-modal representation learning. To address this, we propose the first brain-inspired multimodal SNN framework for audio-visual fusion, built upon a spiking Transformer architecture. Our method introduces four key innovations: (1) spatiotemporal spiking attention, (2) cross-modal residual connections, (3) shared semantic space projection, and (4) contrastive-driven semantic alignment optimization. By performing semantic alignment and residual cross-modal interaction directly in the spike domain, our approach significantly enhances feature consistency and complementarity. We evaluate on three benchmarks—CREMA-D, UrbanSound8K-AV, and MNISTDVS-NTIDIGITS—achieving state-of-the-art performance across all, substantially outperforming existing audio-visual SNN methods. The implementation is publicly available.
📝 Abstract
Humans interpret and perceive the world by integrating sensory information from multiple modalities, such as vision and hearing. Spiking Neural Networks (SNNs), as brain-inspired computational models, exhibit unique advantages in emulating the brain's information processing mechanisms. However, existing SNN models primarily focus on unimodal processing and lack efficient cross-modal information fusion, thereby limiting their effectiveness in real-world multimodal scenarios. To address this challenge, we propose a semantic-alignment cross-modal residual learning (S-CMRL) framework, a Transformer-based multimodal SNN architecture designed for effective audio-visual integration. S-CMRL leverages a spatiotemporal spiking attention mechanism to extract complementary features across modalities, and incorporates a cross-modal residual learning strategy to enhance feature integration. Additionally, a semantic alignment optimization mechanism is introduced to align cross-modal features within a shared semantic space, improving their consistency and complementarity. Extensive experiments on three benchmark datasets CREMA-D, UrbanSound8K-AV, and MNISTDVS-NTIDIGITS demonstrate that S-CMRL significantly outperforms existing multimodal SNN methods, achieving the state-of-the-art performance. The code is publicly available at https://github.com/Brain-Cog-Lab/S-CMRL.