How come when we sleep our eyes go cross-eyed?!
Question:
How come when we sleep our eyes go cross-eyed?
Answers:
When the eyes are open, they each have an image. The brain likes to line up those images so that you see only one of things. As soon as the eyes have fixation on an object, they line up together.
When you sleep, your lids go down, the eyes move up and away from the space between the lids (palpebral fissure) which protects the cornea from exposure. When the eyes open again, the eyes drop back down and fix on the object of regard. It's called Bell's phenomenon (I think). Try closing your eyes and lifting your lid with your finger, you'll see the lower white part of the eye as the cornea bells up.