Many people experience troubled sleep on the first night they’re sleeping in a new house or flat, or when they go on holiday.
Scientists have now found out there’s a very good reason for it: it’s actually a survival mechanism from thousands of years ago.
Imagine sleeping in a new cave: you’re unfamiliar with the environment, you may be unfamiliar with the people, and certainly with predators in the environment. A part of your brain stays on ‘alert’, in case you need to react fast in order to secure your safety.
Your brain is on night watch
In short, the right hemisphere of your brain gets ready for a decent night of rest, while the left hemisphere is on night watch, scientists from the Georgia Institute of Technology in Atlanta have found.
It continues to monitor your new unfamiliar surroundings, just in case you have to make a dash for it, or fight off a predator.
Read: Poor quality sleep linked to brain shrinkage
This condition actually has a name: first-night effect or FNE. By using advanced neuro-imaging techniques as well as polysomnography (a type of sleep study in which your brain waves are recorded, as well as the oxygen levels in your blood, your heart rate and breathing and eye and leg movements while you sleep) the scientists found that the depth of sleep and the slow-wave activity in the left hemisphere of the brain is a lot less than in the right hemisphere.
How the study was done
They recorded the reactions of sleeping students when listening to a variety of unexpected sounds, and found that when played into the right ear, (connected to the left brain hemisphere) they woke up more rapidly than when it was played into the left ear.
If, however, you make it safely through the first night, the differences in the brain waves between the two parts of your brain start tapering off over time as your brain registers that this new place is a safe one in which to sleep. But it can be very inconvenient if you’re staying over in different places on a road trip.
Read: Less sleep may speed brain ageing
There are five distinct phases in each sleep cycle and you go through these cycles between three and five times a night. Each cycle lasts about 90 – 110 minutes.
· The first is a light sleep during which you will awake easily
· The second is called true sleep, and your breathing and heartbeat and brain waves slow down
· The third is a deep sleep during which you are thoroughly relaxed
· The fourth is a very deep sleep. If you are woken up during this phase, you will feel disorientated
· The fifth stage is REM sleep (Rhythmic eye movement) during which you dream.
So what can you do to prevent FNE?
And no, there isn’t really anything you can do to relieve FNE, according to Dr Alison Bentley, Health24’s Sleep disorders expert.
She suggests taking your own pillow or something familiar with you when you have to sleep elsewhere, as this might make it feel more like home, and might make it easier for you to get a decent night’s rest.
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