Why Do Some People See ‘Shadows’ Moving on Walls?

Sometimes, people see shadows moving on walls, even when there are no real shadows. This happens because the brain is trying to make sense of what it sees. Imagine you're in a dark room with a small light. The light might bounce off your body or clothes and create shapes that look like shadows moving on the wall. Your brain thinks, 'There must be someone else here!' That's why some people see strange shadows, it's just their brain working hard to figure things out.