In the current eLORETA implementation, the solution space was restricted to the cortical gray matter, corresponding to 6239 voxels at 5×5×5 mm spatial resolution. The Montreal Neurologic Institute average MRI brain (MNI152) [45] was used as a realistic head model for which the lead field was computed [46]. Validation for the new improved eLORETA tomography rests upon the abundant published validation for the previous LORETA and sLORETA methods. For instance, excellent localization agreement has been reported in multimodal imaging studies with functional MRI [47], [48], structural MRI [49], and PET [50]–[52]. Further validation based on accepting as “ground truth” the information provided by intracranial recordings in humans has been reported in a number of articles [53], [54].
