Dr. Sled is widely recognized for his contributions to the development of MRI technologies. He was the first to describe comprehensive quantitative magnetization transfer imaging in humans and is the author of the widely used neuroimaging software N3. He has also made contributions in the areas of MR relaxometry, tissue microstructure / diffusion, perfusion, and morphometric techniques. His recent work has focused on applications of MRI, ultrasound, and X-ray CT in experimental mice to understand gene / environment / phenotype relationships in disease. A particular area of interest is formal methods for describing the patterning differences that characterize a phenotype.