What Is the Ideomotor Effect?

The ideomotor effect refers to people making motions or acting without conscious deliberation. Many are familiar with this kind of motion as a response to physical pain, or in common reflex tests. This idea can also be called the Carpenter effect, which is named after a 19th century scientist who studied the relationship between body and mind.

Although some instances of ideomotor effects are fairly straightforward, others raise substantial questions about the proper use of predictive tools, and even about the interaction of human beings with elements considered to be on the fringe of scientific knowledge. Some of these techniques that are common to various modern cultures include “water witching,” or dowsing, as well as the use of the Ouija board. Many scientists have suggested that these activities are based on an ideomotor effect rather than on other theoretical causes commonly attributed to the supernatural. “Automatic” or “spirit” writing is another phenomenon that some ascribe to the ideomotor effect, where people seem to write without thinking, producing some intriguing narrations on paper that have seemed to confound rational explanation.

Inventions that make use of ideomotor effects have also generated debate on the lawful use of predictive devices in homeopathic medicine. One case that is often cited is the use of a “Toftness radiation detector” by chiropractors. According to its proponents this machine allows doctors to identify problem areas by processes that some describe as based on an ideomotor effect. Other examples include the use of enclosed spaces to capture theoretical energies, such as contraptions sometimes called “black boxes” or “orgone boxes” that are thought to be able to contain or distribute spiritual or metaphysical energies.

Some renowned scientists have found much evidence of the possibility that bodies can act independently of deliberate thought. One theory is that these reflexive actions carry out a category of intent that is hidden within the mind. Scientists who have done work on this phenomenon include Michael Faraday, as well as other scientific authorities of the modern era. Much work has also been done on the unconscious mind, and explaining how it may contribute to these sorts of behaviors. Linking unmapped areas of the mind to theoretical phenomena like the ideomotor effect is a promising area in cognitive science, where today’s technologies, such as neural networks, could someday be used to explain some of these obscure connections between behavior and thought.