these findings in an independent and substantially larger sample (N = 98; 49 depressed patients) using a denser 67-channel recording montage so as to identify and quantify the underlying scalp current generator patterns derived from reference-free CSD-PCA methodology. Findings were compared with analogous CSD-PCA solutions obtained from the previous, smaller sample (N = 40) using a 31-channel montage, and interpreted in the context of solutions obtained for other auditory oddball tasks.
