The First-Night Effect: Why Your Brain Won't Let You Sleep in Unfamiliar Places

Robinson Leoni knows the pattern by heart. On his home mattress, he sleeps seven hours straight. The first night in a hotel room—whether he brings earplugs, whether the bed is comfortable, whether he feels stressed—his smartwatch logs something closer to five. He wakes repeatedly. The quality never matches what he gets at home, even though he insists he feels fine during the day, no anxiety he can name. "I notice I wake up continuously," said Leoni, a sales director who travels for work one or two times a month. He is experiencing what sleep researchers call the first-night effect, and he is far from alone.

The phenomenon is real enough that dozens of studies have documented it, and sleep specialists believe it traces back to our evolutionary past. Anna Wick, a senior sleep researcher at the University of Freiburg in Switzerland, explains the mechanism simply: "It's assumed to be an adaptation response that the sleeping brain remains vigilant in this unfamiliar environment." The brain, in other words, never fully powers down when you're somewhere new. It keeps one eye open—literally. Ahmad Mayeli, a psychiatry professor and sleep researcher at the University of Pittsburgh, has measured this in brain scans. His research shows that the frontal lobe, the region responsible for the deepest stages of sleep, stays more active than it should. People don't just sleep less in new places; they sleep less deeply. "Like in dolphins, part of the brain is awake when you are sleeping," Mayeli said. "It's not exactly like dolphins, but still, studies show part of the brain is sleeping less." On average, most people lose between twenty and thirty minutes of sleep the first night away from home.

Age shapes how pronounced the effect becomes. Children, adolescents, and older adults all experience it more intensely, with the disruption generally worsening as people age. Those in their twenties, Mayeli noted, are the least affected—"maybe it's the sweet spot." The evolutionary explanation makes a certain kind of sense: historically, unfamiliar places were dangerous places to rest. Your brain hasn't evolved past that wariness, even if you're checking into a Marriott. "It doesn't matter if it's a Marriott hotel or it's the savannah," Mayeli said. "Your brain hasn't gotten the memo that this place is completely safe."

But the first-night effect isn't purely biological. Psychologist Lisa Strauss, who specializes in cognitive behavioral treatment of sleep disorders, points out that anxiety plays a significant role, especially for people who are already prone to worry. Travel itself—the disruption, the jet lag even within the same time zone, the unfamiliar sounds and lights—can interfere with sleep. A flashing smoke detector in a hotel room, tension from visiting family members you're not close with, the general strangeness of the place: all of these pile on. For some people, though, the first night away actually brings better sleep. Those exhausted from travel, or people who associate their home bed with years of insomnia, sometimes sleep more soundly in a new environment. The effect typically fades after the first night, Wick said, as the brain acclimates.

Leoni has noticed that his own anxiety about sleep can become self-fulfilling. He'll talk to a colleague before heading to his hotel room and say out loud, "I'm not going to sleep anyway." The worry itself becomes the obstacle. Strauss recommends starting with basic sleep hygiene: a cool, dark room, a consistent bedtime, screens off well before sleep. But she suggests doing these things in the days or weeks before a trip, not just when you arrive. Once you're in the new place, spend extra time in the bed doing something familiar and peaceful—reading, for instance—to make the novelty feel less threatening. Bring objects from home: a favorite pillow, a blanket. For people with significant anxiety, Strauss recommends visualization: imagine yourself in a safe, familiar place in nature, a favorite hike or beach. Notice the anxiety without judgment, then repeat calming phrases. "May you know that you are safe. May you know that you are loved. May you be at peace."

Mayeli emphasizes that the first-night effect isn't a crisis. Missing an hour or two of sleep one night is recoverable. But if something important is happening the next day—a major meeting, a presentation, an event that matters—his advice is simple: arrive a day early. "If tomorrow matters, get there a night early," he said, "so you'll sleep like yourself when it counts." The brain's ancient vigilance system will stand down eventually. It just needs time.