aMRI holds great potential for assessing brain motion/strain using images acquired from readily-available sequences. However, registration is needed to extract displacements from the motion-amplified images, which may limit its accuracy. In this study we separately assessed the errors induced by registration limitations and by imperfections in the aMRI amplification. Displacements were extracted from aMRI and DENSE-amplified images using a common registration algorithm, which were then compared to a ground truth. Although significant differences were found between DENSE-amplified images and aMRI, the aMRI-derived displacements were comparable to the ground truth, strengthening the potential of aMRI for investigating brain motion in disease.