The Spooky Science Behind Ouija Boards

Ouija boards have been associated with the supernatural since the 19th century, with claims it allows the living to communicate easily with the dead, but really the Ouija is merely a novelty product.
However, there is some real science behind the way people interact with the “spirit board” when they get together, and the magic can be cast aside in favor of one scientific explanation- the ideomotor effect:

The ideomotor effect occurs when someone moves themself or an object without being conscious of their actions. This combined with a strong subconscious need for an answer, like what one might feel when using a Ouija board, leads to players moving the planchette without any knowledge of doing so.

So the desire to "speak" through the board can make people move their hands without knowing it, and what seems like intentional deception is really just subconscious desire facilitated by the fingers.

Read The Spooky Science Behind Ouija Boards at mental_floss