Ideomotor effect

Ideomotor phenomenon is a psychological phenomenon wherein a subject makes motions unconsciously.

The ideomotor response (or "ideomotor reflex"), often abbreviated to IMR, is a concept in hypnosis and psychological research. It is derived from the terms "" (idea, or mental representation) and "" (muscular action). The phrase is most commonly used in reference to the process whereby a thought or mental image brings about a seemingly "reflexive" or automatic muscular reaction, often of minuscule degree, and potentially outside of the awareness of the subject. As in reflexive responses to pain, the body sometimes reacts reflexively with an ideomotor effect to ideas alone without the person consciously deciding to take action. The effects of automatic writing, dowsing, facilitated communication, and Ouija boards have been attributed to the phenomenon. Mystics have often attributed these effects to paranormal or supernatural force. Many subjects are unconvinced that their actions are originating solely from within themselves.

The associated term "ideo-dynamic response" (or "reflex") applies to a wider domain, and extends to the description of all bodily reactions (including ideo-motor and ideo-sensory responses) caused in a similar manner by certain ideas, e.g., the salivation often caused by imagining sucking a lemon, which is a secretory response. The notion of an ideo-dynamic response contributed to James Braid's first neuro-psychological explanation of the principle through which suggestion operated in hypnotism.

With the rise of Spiritualism in 1840s, mediums devised and refined a variety of techniques for communicating with the spirit world including table-turning and planchette writing boards (the precursor to later Ouija boards). These phenomena and devices quickly became the subject of scientific investigation.

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