BNMTrans: A Brain Network Sequence-Driven Manifold-Based Transformer for Cognitive Impairment Detection Using EEG

Identifying mild cognitive impairment (MCI) is vital for Alzheimer's disease prevention. As neurodegenerative diseases progress, synchronous activity in electroencephalography (EEG) - indicating functional connectivity - changes due to neural system deterioration. Thus, developing geometric learning to decode the functional brain structure is essential. Techniques such as graph neural networks and Riemannian manifolds show potential in analyzing non-Euclidean data. However, existing approaches neglect to combine synchronous activity with temporal dependence and still remain insufficient for MCI detection. This paper proposes the Brain Network sequence-driven Manifold-based Transformer (BNMTrans) to identify MCI patterns from EEG data. BNMTrans leverages its strengths by extracting features from sequential brain networks through the self-attention mechanism, guided by the geometric correlations within the Riemannian manifold. By integrating long-term temporal dynamics and structural relationships within manifold space based on functional connectivity, this approach outperforms others in EEG feature comparisons and state-of-the-art evaluations based on clinical data from 89 subjects (46 MCI, 43 healthy controls) at a local hospital. Our work has significance for both MCI clinical management and technical progression in the EEG field.