An idea alone can sometimes cause physical effects – for example, imagining sucking a lemon can provoke salivation, or an expression of bitterness on the face of the person visualising it; or thinking about tying up shoelaces can make our hands twitch slightly, as if we were actually carrying out the action.
In some cases, our physical response to an idea may occur outside our consciousness awareness, and in these instances we may mistake as ‘paranormal’ actions performed by our own body and motivated by our own ideas.
Experiments have shown that common ‘spiritual technologies’, such as ouija boards, pendulums, dowsing rods and automatic writing, can produce their results through the ideomotor effect. Both the idea provoking the movement of the experiencer’s hand, and the awareness of moving that hand, may be unconscious. In this case it can seem that some other external agency (a ‘spirit’) is moving the device and communicating independently.
- Definition and history of the ideomotor effect, from Wikipedia.
- An amusing video sequence by illusionists Penn and Teller, debunking Ouija boards.