Error bars refer to the first and third quartiles (of localization error distribution). Two noise types, namely, additive white Gaussian noise (AWGN) and additive colored Gaussian noise (ACGN) with SNRs of 5 dB and 20 dB are simulated. The simulations are repeated for both EEG and sEEG electrodes and with a region of interest (ROI) assumption (refer to section 2 for more details). As it can be seen, the ROI assumption can improve the source localization, however it requires some extra information, which is not generally available.