Decoupling Time and Space: A Temporally Conditioned Refinement for EEG Source Imaging
This study addresses the ill-posed nature of spatial inversion in EEG source imaging and the inherent trade-off between temporal modeling capability and inference cost. To this end, we propose a dual-stream decoupled framework that explicitly separates spatiotemporal processing to reduce computational overhead. Methodologically, a Transformer-based temporal encoder extracts global dynamic conditions, while a factorized spatiotemporal attention mechanism preserves sensor-level features. A source-space refiner then enables high-fidelity, time-step-wise reconstruction. Experimental results demonstrate that the proposed model significantly outperforms baselines under challenging high-noise, multi-source scenarios on synthetic data. Furthermore, it successfully transfers to real-world EEG age-group decoding tasks, achieving synergistic improvements in both accuracy and efficiency.