Do you find yourself tossing and turning during your first night at a hotel or a new house? This common phenomenon is scientifically known as the ‘First Night Effect.’ Researchers at the University of Salzburg in Austria have recently discovered that this happens because a part of our brain refuses to sleep deeply in an unfamiliar environment, acting as a “night watchman.”

Using EEG machines to monitor brain activity, scientists found that in a new setting, the brain perceives subtle ambient sounds or movements as potential threats. This is an ancient evolutionary trait; in prehistoric times, staying partially alert during sleep was crucial to survive predator attacks. The study revealed that when sleepers heard familiar voices, their brains felt secure and drifted into deep sleep. However, unfamiliar sounds immediately triggered an alert response. Experts suggest that this isn’t a disorder but a heightened state of survival instinct. To trick your brain into sleeping better while traveling, carrying your own pillow or a familiar fragrance can help signal a sense of safety to your subconscious.