Genes that Control How Much We Dream (IMAGE) RIKEN Caption Acetylcholine receptors Chrm1 and Chrm3 (illustrated as Sandman gnomes 1 and 3) are essential for REM (dream) sleep. In this visual description of the study, the receptors help a mouse dream about a sleeping cat and Michel Jouvet (1925-2017), a pioneer of REM sleep studies. Credit Copyright Hiroko Uchida Usage Restrictions This image cannot be used without permission from Hiroko Uchida 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.