Adaptive-Similarity-Based Brain Dynamic Functional Connectivity with Spatial-Temporal Attention and Domain Adaptation for Schizophrenia Diagnosis

Dynamic functional connectivity (DFC) can capture the neural activity changes over time in the brain. Most existing DFC constructions rely on sliding windows, which can be highly impacted by window type and width. In addition, previous methods fail to fully optimize for discriminative spatial-temporal (ST) information and can suffer from inter-site heterogeneity, resulting in suboptimal sensitivity to brain disorders. Here, we propose a novel DFC model by combining ST attention-based bidirectional long short-term memory (BiLSTM) and multi-source domain adaptation (DA) to extract inherent ST information and reduce inter-site heterogeneity. An adaptive similarity sparse representation (SR)-based Kalman filter is proposed to obtain DFC with accurate connectivity strength at each time point. ST attention modules are integrated into BiLSTM to capture discriminative ST features with a maximum mean discrepancy (MMD)-constrained module for multi-source DA. Experimental results show that our method achieves high accuracy (90.67%±2.43%) in discriminating schizophrenia (SZ) from controls, outperforming 7 DA, 6 ST, and 5 DFC models. These results demonstrate the effectiveness of the proposed DFC model, which can be used to investigate multi-site fMRI DFC for the diagnosis of brain disorders.