Ever Struggle To Sleep On Your First Night Somewhere New? Be Grateful – Your Brain Is Just Looking Out For You

I’m not alone though, because there’s literally a name for this: the first night effect.

It’s not just a problem for travelers (who wants to be sleep-deprived when you’ve flown into town for a big work meeting?), but also for sleep scientists and clinicians.

If a doctor believes you may be suffering from a sleep disorder, they might recommend spending a night in the lab to be monitored, but that’s not going to be much use if you can’t actually get to sleep.

“First recognized in 1964, [the first night effect] has been a critical topic in sleep research due to its potential to bias sleep results,” wrote the University of Pittsburgh’s Ahmad Mayeli and Fabio Ferrarelli in a 2024 editorial published in a special issue of the journal SLEEP.

The pair were discussing results from a paper included in that issue by psychology researcher Anna Zoé Wick and colleagues. The team found that the first night effect can be apparent both in familiar and unfamiliar environments – in one of their experiments, volunteers spent two non-consecutive nights in a sleep lab and in their own homes.

Sleep studies often include some acclimation for participants before diving into the data collection. This research suggests that’s a good idea and may also be needed if participants are going to be monitored at home.

So, the first night effect is very real… but why?

The "night watch"

In a recent interview published by the Associated Press (AP), Mayeli suggested that the first night effect is a result of our brains being on high alert in a new environment.

“It doesn’t matter if it’s a Marriott hotel or it’s the savannah. Your brain hasn’t gotten the memo that this place is completely safe,” he said.

He said that most people experience this to some extent, even if they don’t really notice – it could just be a few minutes of lost sleep, or you could be tossing and turning for hours.

Anxiety is among the most common causes of insomnia, but unfortunately that relationship works both ways, with poor sleep being a risk factor for poorer mental health. You can quickly end up in a vicious cycle.

Fortunately, if the only source of anxiety keeping you up is being in unfamiliar surroundings, that should fade quickly as you get used to them, hence why we’re talking about a “first night effect” rather than a “first week effect”.

One study of the effect by scientists at Brown University in 2016 added an intriguing result into the mix. When 35 healthy volunteers had their brains scanned as they slept, it revealed that on their first night in a new place, the two hemispheres of their brains were not equally asleep.

In fact, the left side of the brain was significantly “less asleep” than the right.

This mirrors what we see in some birds and marine mammals like dolphins (although probably not sperm whales, as IFLScience recently discovered) – they practice unihemispheric sleep, resting only one half of their brains at a time so they can avoid drowning/falling out of the sky.

The authors of the 2016 study referred to this similar phenomenon in humans as a “night watch”, protecting the sleeper in an unfamiliar place.

Good sleep hygiene can go a long way

That’s very nice of your brain to be looking out for you and all that, but it’s not all that helpful if you’re trying to maximize the first day of your vacation or stay awake for the opening day of a conference.

So, is there anything you can really do to combat the first night effect?

There are lots of general sleep hygiene tips that may help, regardless of the cause of your insomnia. Try and limit distractions like electronic devices and give yourself some wind-down time before bed if you can – meditation, a warm bath, that kind of thing.

If you can figure out the hotel A/C then the ideal temperature for sleeping is often said to be between 16 and 18°C (60-65°F), although recommendations do vary on that.

If there are any comforting smells or sounds you like they might help you feel calmer – a lavender pillow spray, for example, or a playlist with your favorite soundscape. The lead author of the 2016 study suggested to Medical News Today that taking your own pillow along with you could help if you have to sleep somewhere new.

I can't personally attest to them, but there are all manner of apparently military-backed and insect-inspired "get-to-sleep-quick" techniques out there. Me personally, I'm a fan of the old counting sheep method.

Ultimately, if you know you need to be on top form for an event, consider arranging your travel so that you have at least one night to get acclimated first.

Mayeli told AP, “If tomorrow matters, get there a night early, so you’ll sleep like yourself when it counts.”