Eli5: Why do many people struggle to sleep on the first night in a different bed or environment?

Question

Eli5: Why do many people struggle to sleep on the first night in a different bed or environment?

In: 6

Answer 1

it’s because your brain is unsure if the new place is “safe” or not. you never fully go into deep sleep cycles because your brain subconciously feels as if it needs to stay somewhat alert in the event that you need to quickly switch into flight or fight to escape danger.