Fluorescing Neurons (image) California Institute of Technology Share Print E-Mail Caption Optogenetic (green) and chemogenetic (red) transgenes are expressed in the dopaminergic (blue) neurons in the dorsal raphe nucleus. Dopaminergic neurons are implicated in moderating the sleep/wake cycle. Credit Gradinaru lab/Caltech Usage Restrictions WITH IMAGE CREDIT Share Print E-Mail 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.