Lately I've been experiencing movement out of the corner of my eyes, every time I'm thinking it's a person walking by, but when I turn my head to look, there's no one there. The last experience happened only today, the image was of a male adult wearing white top, black trousers, and I think long hair. If it's an illusion, my question would be why is my mind/eyes playing tricks on me? The person I described above looks like no one (didn't see the face) nor do I know anyone with long hair. If it's a ghost, the idea is kinda scary to think that I am able to see ghosts on occasion walking about. Your thoughts?