His research focus is molecular imaging and blood diagnostics of neurodegenerative diseases, particularly Alzheimer's Disease, for better understanding, earlier more accurate detection, and to facilitate development of early therapeutic interventions. He has over 400 publications and is in the 2021 Highly Cited Researcher list of the top 1% world-wide for neuroscience with over 7,500 citations of his papers per year, and has received the 2011 US Society of Nuclear Medicine Kuhl-Lassen Award for Outstanding Contribution to Brain Imaging and the 2016 Christopher Clark Award for advancing human brain amyloid imaging.