Spectral power differences for single recordings (N≥2480) across all scalp sites (top panel), frontal channels only (F1, F2, F3, F4, F5, F6, F7, F8, and Fz, middle panel), occipital channels only (POz, Oz, O1, and O2, bottom panel) at each spectral point for data that was visually inspected data, visually inspected + ADJUST, and visually inspected + MARA. MARA and ADJUST produce generally consistent results across recordings. Both ADJUST and MARA adequately preserved alpha power in most, but not all cases. MARA more frequently reduced high frequency power over frontal channels than ADJUST.