So it’s easy because you can’t see well in the dark. Humans’ low-light vision is much worse than, for example, many predators that humans have had to watch out for in the wild over time.
It has been important for people to be alert after dark, when imagining scary and dangerous things could have helped to stay alive.
A person can also easily think they see something scary in the dark. When something is dimly seen, the brain often tries to give it some meaning. For example, a swaying branch in a window can look like a giant hand.
All in all, sight is a very important sense for us. It is the best way to recognize things and move around in the environment.
When you can’t see, it’s often appropriate to be careful. If you are not used to being in the dark, you may feel insecure and easily imagine something scary in the dark.
Kaisa Tiippana
university lecturer in perceptual psychology
university of Helsinki