is an American neuroscientist and Biotech executive. His research has contributed to our understanding of the molecular mechanisms that regulate development and function of the mammalian brain. A major focus of his research has been to identify mechanisms that regulate neuronal connectivity and the effects of neuronal activity on brain development. He served as the Global Head of Neuroscience Discovery at F. Hoffmann-La Roche from 2011 to 2016 and as founding CSO of E-Scape Bio from 2016-2017. He was the Head of Research and Early Development at Biogen from 2017-2020 and is currently the CEO of Unity Biotechnology.