by thenewgreen

When you check into a hotel room or stay with a friend, is your first night of sleep disturbed? Do you toss and turn, mind strangely alert, unable to shut down in the usual way? If so, you’re in good company. This phenomenon is called the first-night effect, and scientists have known about it for over 50 years. “Even when you look at young and healthy people without chronic sleep problems, 99 percent of the time they show this first-night effect—this weird half-awake, half-asleep state,” says Yuka Sasaki from Brown University.