Figure 5. Harmonic Regression Effectively Removes BCG Artifacts and Recovers Simulated Evoked Responses.
(A) BCG-corrupted test data series (green) and underlying simulated evoked potentials (black). (B) Test data (green) overlaid by clean EEG obtained with harmonic regression (cyan) and ECG-based methods (OBS, top, solid red and AAS, bottom, dashed red). Harmonic regression leaves less residual comb-like pulsatile BCG artifact in cleaned EEG as compared to ECG-based methods. (C) Clean average ERP (thick middle traces) +/− one standard deviation (thin traces) across 200 epochs – obtained with harmonic regression (cyan), OBS (solid red) and AAS (dashed red) atop simulated ERP (black, identical across epochs). Each algorithm yields clean average ERP with morphology matching simulation – although harmonic regression and OBS estimates have lower standard deviations than AAS.