Navid Mohammadi Foumani, Soheila Ghane, Nam Nguyen, Mahsa Salehi, Geoffrey I. Webb, Geoffrey Mackellar
原文摘要
Foundation models for EEG analysis are still in their infancy, limited by two key challenges: (1) variability across datasets caused by differences in recording devices and electrode configurations, and (2) the low signal-to-noise ratio (SNR) of EEG, where neural activity is often buried under artifacts and non-brain sources. To address these challenges, we present EEG-X, a device-agnostic and noise-robust foundation model for EEG representation learning. EEG-X introduces a location-based channel embedding that enables robust transfer across heterogeneous EEG devices and electrode layouts. To improve robustness against noise, EEG-X employs a novel noise-aware masking-reconstruction strategy that reconstructs artifact-cleaned signals rather than raw noisy EEG and introduces a novel Dictionary-based Convolutional Transformation (DiCT) that improves reconstruction-based pretraining by comparing signals in a structured feature space instead of directly in the raw signal space. Experiments across datasets collected from diverse EEG devices show that EEG-X consistently outperforms state-of-the-art methods across multiple downstream tasks and demonstrates strong cross-domain generalization when pretraining and downstream datasets differ in electrode layouts and recording configurations paving the way towards foundation models. The models and code are available at https://github.com/Emotiv/EEG-X.
Modeling long-context electroencephalography (EEG) signals is critical for learning generalizable EEG representations, as EEG recordings are acquired at high sampling rates and often span extended durations that capture evolving neural states beyond short task- specific windows. Transformer-based models have shown promise in modeling short sequences of a few seconds; however, their quadratic complexity limits scalability to longer contexts. Moreover, substantial variability in electrode montages across datasets and recording devices poses a major challenge for building EEG models that generalize across domains. We propose SAMBA, a self-supervised learning framework with a Mamba- based U-shaped encoder-decoder architecture, which effectively captures long-range temporal dependencies and montage variability in EEG data. Leveraging the inherent ability of Mamba in processing long context sizes, we introduce: (1) Temporal Semantic Random Masking for semantic-level sequence reconstruction, (2) a Multi-Head Differential Mamba module to suppress redundancy and emphasize salient temporal structures, and (3) a Coordinate-Driven Spatial Embedding that learns unified embeddings in a three- dimensional Euclidean space, enabling robustness across devices. Experiments on thirteen EEG datasets across diverse tasks, electrode configurations, and sequence durations demonstrate that SAMBA achieves competitive or improved performance compared to recent state-of-the-art methods, while maintaining low memory consumption and efficient inference. The learned spatial weight maps exhibit close alignment with task-relevant neurophysiological regions, highlighting the interpretability of SAMBA. The code is available at: https://github.com/Jiazhen-Hong/SAMBA