Why The System Needs Sleep (IMAGE) PLOS Caption An illustrated representation of multilevel-system circuitry sleeping. Credit Paul Franken, <a href="mailto:paul.franken@unil.ch">paul.franken@unil.ch</a> Usage Restrictions CC-BY - Redistribution allowed with credit. 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.