If I close my eyes, it is mostly to avoid eye-strain from trying too hard to see in the dark. I have spent many thousands of hours in the dark -- loading and unloading sheet film and developing sheets in open trays. My Jobo Expert Drums sure have made a difference!
I can 'see' my hands dimly in the dark. That is, my brain can form the image of my hands in front of me based on the position/muscles of my hands. A little spooky, but I can never see what my hands are holding (film, white trays), so it is not a matter of light leaking into the room. Perhaps I have spent too much time alone in the dark!