Objective: Local field potential (LFP) recordings from deep brain stimulation (DBS) electrodes are often contaminated with electrocardiographic (ECG) artifacts that hinder the detection of disease-specific electrical brain activity. Methods: Three ECG suppression methods were evaluated: (1) QRS interpolation of the Perceive toolbox, (2) template subtraction, and (3) singular value decomposition (SVD). LFPs were recorded with the Medtronic PerceptTM PC system in nine Parkinson's disease patients with stimulation OFF (“OFF-DBS”; anode disconnected) and ON at 0 mA (“ON-DBS 0 mA”; anode connected). Findings were verified with simulated ECG-contaminated time series. Results: ECG artifacts were present in 10 out of 18 ON-DBS 0 mA recordings. All ECG suppression methods drastically reduced artifact-induced beta band (13–35 Hz) power and at least partly recovered the beta peak and beta burst dynamics. Using external ECG recordings and lengthening artifact epoch length improved the performance of the suppression methods. Increasing epoch length, however, elevated the risk of flattening the beta peak and losing beta burst dynamics. Conclusions: The SVD method formed the preferred trade-off between artifact cleaning and signal loss, as long as its parameter settings are adequately chosen. Significance: ECG suppression methods enable analysis of disease-specific neural activity from signals affected by ECG artifacts.
|Early online date||2 Dec 2022|
|Publication status||Published - Feb 2023|
- Local field potentials
- Parkinson's disease