Too much stress can keep you up at night. A pressing deadline, watching the news, anxiety—sometimes you can find yourself tossing and turning, even though you are so tired from stress. Many research studies have linked stress to sleep issues, and insomnia. And now scientists at Cold Spring Harbor Laboratory (CSHL) have pinpointed the neural circuit responsible for sleepless nights due to stress. Their findings also revealed that the same circuit induced changes in the immune system.