Long Day (IMAGE) University of California - San Diego Caption This image reveals the activity of PaVN neurons in rats that were exposed to light mimicking a longer-than-usual day that elicits stressed behaviors. Credit UC San Diego Usage Restrictions Must be used in conjunction with PNAS paper on stress and neurotransmitter switching mechanisms. 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.