A noninvasive MRI approach that can detect the Alzheimer's disease in a living animal, well before typical Alzheimer's symptoms appear, has been developed by researchers. The research team created an MRI probe that pairs a magnetic nanostructure with an antibody that seeks out the amyloid beta brain toxins responsible for onset of the disease. The accumulated toxins, because of the associated magnetic nanostructures, show up as dark areas in MRI scans of the brain.