Matthew Butler is an assistant professor in the Oregon Institute of Occupational Health Sciences at Oregon Health & Science University. The goals of the Butler Laboratory are to learn why disruptions of our internal body clocks and sleep, as often encountered by shift workers, increase the risk for disease. Both light and food are strong synchronizers of the internal circadian clock, but these signals are often at odds in modern society. Using neuroendocrine and behavioral approaches, we are studying how environmental cues synchronize clocks, and how these in turn regulate physiology and behavior. Our choice of model and methods are also informed by ongoing epidemiological studies of human populations.