IEEE Transactions on Neural Networks and Learning Systems

Researchers have proposed U2Multi-UDA, a unified multilevel multisource unsupervised domain adaptation framework for motor imagery brain-computer interfaces that raised mean accuracy by 2.69, 1.89 and 3.83 percentage points over the best-performing baselines on two public datasets and one self-constructed dataset, with consistent gains in Kappa. It tackles two persistent obstacles, wide variation between subjects and a shortage of labeled target-domain data, which existing methods address at only one level of adaptation, whether domain alignment, feature interaction or model fine-tuning. The single pipeline aligns source and target distributions with optimal transport while mutual information estimates how relevant each source domain is to the target, fuses spatio-temporal EEG features through multisource cross-attention guided by those weights and reinforced with pseudolabels, and closes with segmented weight-decomposed low-rank adaptation for parameter-efficient fine-tuning that curbs overfitting.

Researchers propose a function predefined convolutional neural network (FPCNN) for decoding spontaneous EEG in brain-computer interfaces. Its learnable function predefined convolution (FPC) layer searches for the key spatial-frequency parameters of spontaneous EEG so the parameters carry clear physical meaning, and it builds trainable orthogonal detectors on the FPC to capture complex phase-varying signals. On three spontaneous EEG datasets, FPCNN outperformed state-of-the-art methods by 2.09%, 3.08% and 3.41%, with single-round training and testing taking just 67.96 and 19.36 seconds on non-GPU hardware, which the authors say makes it suited to EEG processing in diverse environments.