> EEG - 10 channels dry, soft-polymer active electrodes > EMG - 4 channels > EXG - 2 channels > EOG - 2 channels I thought "EXG" was generally used to indicate

> EEG - 10 channels dry, soft-polymer active electrodes > EMG - 4 channels > EXG - 2 channels > EOG - 2 channels I thought "EXG" was generally used to indicate "EEG, EMG, ECG or EOG" ... but in the context where they've listed the others, I don't know what the separate "EXG" channels are supposed to measure. Is this like, "we have two spare dangling electrodes and you're free to stick them wherever -- you decide"?