With the rise of
Spiritualism in 1840s,
mediums devised and refined a variety of techniques for communicating, ostensibly, 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. The term
ideomotor was first used by
William Benjamin Carpenter in 1852. In a
scientific paper that specifically discussed the means through which
James Braid's "hypnotism" produced its effects, Carpenter derived the word
ideomotor from the components
ideo, meaning "idea" or "mental representation", and
motor, meaning "muscular action". In the paper, Carpenter explained his theory that
muscular movement can be independent of
conscious desires or emotions; that the efficacy of hypnotic suggestion was contingent upon the subject's concentration upon a single (thus, "dominant") idea. In 1855, Braid explained his decision to abandon his earlier term "mono-ideo-motor", based on Carpenter's (1852) "ideo-motor principle", and adopt the more appropriate and more descriptive term "mono-ideo-dynamic". His decision was based upon suggestions made to Carpenter (in 1854) by their friend in common,
Daniel Noble, that the activity that Carpenter was describing would be more accurately understood in its wider applications (viz., wider than pendulums and ouija boards) if it were to denominated the "ideo-dynamic principle":In order that I may do full justice to two esteemed friends, I beg to state, in connection with this term
monoideo-dynamics, that, several years ago, Dr. W. B. Carpenter introduced the term
ideo-motor to characterise the reflex or automatic muscular motions which arise merely from ideas associated with motion existing in the mind, without any conscious effort of volition. In 1853, in referring to this term,
Daniel Noble said, "
Ideo-dynamic would probably constitute a phraseology more appropriate, as applicable to a wider range of phenomena." In this opinion I quite concurred, because I was well aware that an idea could
arrest as well as
excite motion automatically, not only in the muscles of voluntary motion, but also as regards the condition of
every other function of the body. I have, therefore, adopted the term
monoideo-dynamics, as still more comprehensive and characteristic as regards the true mental relations which subsist during all dynamic changes which take place, in every other function of the body, as well as in the muscles of voluntary motion.Scientific tests by the English scientist
Michael Faraday, Manchester surgeon
James Braid, the French chemist
Michel Eugène Chevreul, and the American psychologists
William James and
Ray Hyman have demonstrated that many phenomena attributed to spiritual or paranormal forces, or to mysterious "energies", are actually due to ideomotor action. Furthermore, these tests demonstrate that "honest, intelligent people can unconsciously engage in muscular activity that is consistent with their expectations". They also show that suggestions that can guide behavior can be given by subtle clues (Hyman 1977). Some operators claim to use ideomotor responses to communicate with a subject's "
unconscious mind" using a system of physical signals (such as finger movements) for the unconscious mind to indicate "yes", "no", "I don't know", or "I'm not ready to know that consciously". A simple experiment to demonstrate the ideomotor effect is to allow a hand-held pendulum to hover over a sheet of paper. The paper has words such as "yes", "no", and "maybe" printed on it. Small movements in the hand, in response to questions, can cause the pendulum to move towards the words on the paper. This technique has been used for experiments in
extrasensory perception,
lie detection, and ouija boards. This type of experiment was used by
Kreskin and has also been used by illusionists such as
Derren Brown. A 2019 study of automatic pendulum movements using a motion capture system showed that pendulum effect is produced when the fingers holding the pendulum generate an oscillating frequency close to the resonant frequency of the pendulum. At an appropriate frequency, very small driving movements of the arm are sufficient to produce relatively large pendulum motion. == Uses ==