Ideomotor effect

The ideomotor effect is a psychological phenomenon wherein a subject makes motions unconsciously, especially while attributing the motion to a paranormal or supernatural force in which he/she believes. Unexplained phenomena such as applied kinesiology, automatic writing, dowsing, facilitated communication, and Ouija boards can be attributed to the ideomotor effect. The effect is extremely powerful and many subjects cannot be convinced that their actions are originating solely in their own minds.

The term was first used, in most accounts, by William Carpenter around 1852 to explain his theory that muscular movement can be independent of conscious desires or emotions. Later scientific tests planned and conducted by William James, Michel Chevreul, Ray Hyman and Michael Faraday have all shown that some phenomena attributed to paranormal forces are actually due to the ideomotor effect.