Yes of course. It's because you can not see. I sometimes bump into things while feeling my way around a dark room.

Yesterday on the Ripa and Michael talk show, they asked if anyone would go into a dark haunted house naked. Imagine that, naked and can not see. Then noise and things jump at you. Sounds exciting ?

I know that I should not be afraid, but primal urges toward fear tend to overpower rationality. When it is so dark that I cannot see, I do, in fact, become afraid. Thankfully, this does not happen often and there is almost always a source of at least dim light for me to see with. Even things like a tiny light on an electronic are sufficient to make me no longer scared.