BCIwiki (bciwiki.com) — A diffusion-guided denoising network restored 4.88 to 5.59 percentage points of motor-imagery decoding accuracy after removing cardiac artifacts from EEG across 4 public datasets, researchers at Northwestern Polytechnical University reported in Journal of Neural Engineering on September 22, 2026 (PMID 42772331; DOI 10.1088/1741-2552/aeab36).
Physiological artifacts from eye movements, muscle activity and heartbeats degrade EEG recordings and can affect downstream brain-computer interface (BCI) analysis. The Diffusion-Guided Artifact Denoising Network (Diff-ADN) is a compact single-channel framework with 2 stages: severity-conditioned reconstruction, followed by diffusion-guided residual refinement. Forward noising and velocity prediction supervise the second-stage encoder during training, but inference needs only a single deterministic residual correction, with no iterative reverse-diffusion sampling.
Tested at contamination levels from -7 to +2 dB, Diff-ADN reached mean Pearson correlations of 0.936, 0.839, 0.886 and 0.844 for ocular (EOG), muscular (EMG), cardiac (ECG) and mixed EOG+EMG artifacts. With independently recorded artifact sources, performance varied by type: EOG and EMG showed larger reductions, while PTB and INCART ECG differed from the MIT-BIH reference by 0.026 and 0.014. The largest accuracy recovery, 21.90 percentage points, came with PTB ECG artifacts on the BCI IV-2a dataset at -6 dB.
The framework processes 2-second segments in 12.52 to 17.08 ms on the tested CPU. The authors said the results show that better waveform reconstruction does not necessarily translate into uniform recovery of BCI decoding accuracy.