Electrode Pop, Baseline Drift & Movement Artifact Rejection
Sudden head movements, electrode shifts, and sweating cause high-amplitude impedance discontinuities ("electrode pops") and ultra-slow DC drift that distort downstream spectral estimations.
The Mechanics of Electrode Pops in Tourette Patients
During sudden neck jerks or facial tics, the mechanical pull on electrode leads breaks the conductive gel bridge, creating an exponential voltage step that can reach up to 1000 µV in a single channel.
Because electrode pops are non-stationary and localized to a single sensor, global ICA decomposition often fails or spreads the spike across neighboring channels via the inverse unmixing matrix.
How Meridian Handles Electrode Pops & Drift
- Zero-Phase High-Pass Filtering (0.5 Hz): Eliminates slow baseline sway and galvanic skin response without shifting ERP latencies.
- Channel Gradient Variance Thresholding: Automatically identifies single-channel sharp impedance jumps before ICA to prevent artifact leakage.
- Spherical Spline Interpolation: Reconstructs damaged single channels from surrounding electrodes when persistent bad contacts occur.
Restore Contaminated EEG Files
Upload your files to Meridian Engine and receive clean raw .fif files, 500ms epochs, and quantitative proof reports.
Submit Dataset to Meridian Engine →