Why sleep is impossible in new places. Half your brain is 'watching'.

It’s called first-night effect, and we’ve all experienced it.

You’re in an unfamiliar place. Maybe a hotel room, new apartment, a friend’s couch and, even though your walking-dead-tired, you cannot fall asleep.

Maybe it’s the light, maybe it’s the unfamiliar sounds, maybe it’s the fact your body is not accustomed to the mattress, pillow, temperature. Whatever it is, there’s something about trying to fall asleep in an unfamiliar place that sends your mind into that endless rabbit hole of completely pointless conversation… ‘what-ifs’, ‘why can’t I fall asleep’,’stop being stupid, just relax’…

Thankfully, science has shown it’s not all in your imagination – and it has nothing to do with the bed clothes. Instead, it’s down to survival.

New research out of Brown University in Rhode Island has found half your brain, one entire hemisphere, stays alert while you’re sleeping somewhere unusual. This has nothing to do with anxiety, it’s all to do with a phenomena called “interhemispheric asymmetry”, which is associated with protection.

“We found poor sleep in an unfamiliar setting may be linked to an important function of the brain to protect the sleeper from potential danger,” authors of the research Masako Tamaki and Yuka Sasaki wrote for the SBS.. “Sleep quality usually improves dramatically on the second night.”

The reason for this high level of alert that makes it hard to fall asleep is all down to survival. A similar concept is seen in the wild, with certain birds and marine mammals also tossing and turning while sleeping in unusual or risky situations. Some birds sleep with only one side of their brain when they’re on the edge of a group of birds, as opposed to in the centre. This heightened level of brain activity helps them detect potential predators.

“Like some animals, the interhemispheric brain asymmetry that happens on the first night in humans might act as a security guard to protect them from danger,” authors of the research Tamaki and Sasaki said.

That’s right, you should be counting yourself lucky if you can’t fall asleep somewhere unfamiliar. You’ve got a greater chance of survival in the wild than those extremely annoying I-can-actually-sleep-anywhere zombies.

Watch next, the link between sleeplessness and creativity:

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