You’re lying awake, unable to drift off—until you pull your blanket over you, and suddenly sleep comes easier.

Somehow, blankets seem to have a magical quality, comforting us even when the weather is warm. There are actually several reasons behind this attachment, and once you understand them, it’ll all start to make sense.

We at Bright Side looked into the science and psychology behind why we can’t sleep without our blankets—and here’s what we discovered.

Blankets Help Regulate Body Temperature

As warm-blooded beings, our bodies naturally maintain a consistent internal temperature. But during deep sleep, our ability to control body heat decreases. This is where blankets come in—they help stabilize our body temperature, providing warmth when our natural regulation slows down.