Ever found yourself tossing and turning through your first night in a hotel? Or ever slept over at someone else’s place and wondered how they drifted off to sleep so easily when you have been watching the clock for hours? You’re not alone! This phenomenon happens to almost everyone and is called the “first-night effect”.
The “first-night effect” has been studied for centuries, however a recent study conducted by researchers from Brown University has shed a whole new light on the phenomenon. The study, which was published in Current Biology, used a MEG, MRI, and polysomnography to measure brain activity in young, healthy participants while they slept in an unfamiliar place.
The researchers found that in the first night sleeping in a new place, the left hemisphere of the brain showed wakefulness while the right was restful. They theorized that the wakefulness in the left side of the brain is a protective measure. It operates as a “night watch system,” safeguarding you against the new, and possibly dangerous, environment while you are in your most vulnerable state.
Why the left hemisphere? This isn’t yet clear. In the study, the researchers outfitted participants with earphones while they slept. When high-pitched sounds were played through the earphones, the left side of the brain responded more to high-pitched sounds than the right. Sounds on the left were more likely to awaken people than sounds on the right.
This phenomenon is not unique to humans. It has been observed in numerous other animals including whales, dolphins, and birds. Birds are known for sleeping with one eye open, or with one half of their brain awake, to avoid being eaten by night time predators. Dolphins alternate the brain hemisphere that is on alert so they can remain vigilant and prepared for a shark attack.
Of course, these days, humans rarely need their “night watch” system. The “first-night effect” is dubbed so because the wakefulness on the left side of the brain, and its comparative sensitivity to noise, was only observable on the first night that participants stayed in a new place. This means that once your brain deems an environment “safe,” it lets its guard down and allows both brain hemispheres to sleep at the same time.
This news may startle people who travel regularly, because great sleep is so critical for high performance and even one night of poor sleep can have dire effects the next day. If you find yourself staying in a new place and you worry about your sleep quality, try these simple tips:
- Set your hotel thermostat to 60-65 degrees
- If your room isn’t fully dark, consider using an eye mask
- Minimize any disturbing sounds with white noise (some people tune their hotel clock radio between stations to create white noise)
- Bring Som Sleep along on your next trip. It’s a purpose-build sleep supplement that will help you fall asleep more easily and wake up ready to take on the day!