Often when you close your eyelids your eyes are actually moving around faster than they would with them open!
There’s a point in your sleep cycle called REM sleep (rapid eye movement) where your eyeballs go totally mental moving around. It’s actually a really important part of sleep, I’m not sure if we know why it happens though!
I know it can sometimes seem like it – I’ve just spent 5 minutes opening and shutting my eyes with my eyes in different positions – I don’t think they do in any major way.
The movements of your eyes are unbelievably fast, and help you subconsciously see things going on all the time. Plus, if you film it and slow it down really slow, you can see how liquid and mobile the bits of your eyes are. Take a look at this video!