Schematic of the mathematical model. (IMAGE) American Institute of Physics Caption Schematic of the mathematical model. The model consists of two populations of coupled oscillators, where one population represents the central clock in the brain, entrained by light, and the other population represents the peripheral clocks, entrained by food. Credit Huang et al. Usage Restrictions Journalists may use this image only with appropriate credit and when reporting on this research. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.