Reverse speech

Reverse speech is a pseudoscience first advocated by David John Oates which gained publicity when it was mentioned on Art Bell's nightly Coast to Coast AM radio talk show. It claims that during spoken language production, human speakers subconsciously produce hidden messages that give insights into their innermost thoughts. Oates claims that it has applications in psychotherapy, criminology and business negotiation. Its claims have been rejected, however, by mainstream science and academia.

Oates' claim is that, on average, once in every 15–20 seconds of casual conversation a person produces two related sentences—a "forward-spoken" message that is heard consciously, and a "backwards" message unconsciously embedded in the person's speech. These two modes of speech, forward and backward, are supposedly dependent upon each other and form an integral part of human communication. In the dynamics of interpersonal communication both modes of speech combine to communicate the total psyche of the person, conscious as well as unconscious. Oates claims that backward speech is always honest and reveals the truth about the speaker's intentions and motivations. The most famous recording that allegedly demonstrates this is the speech given by Neil Armstrong at the time of the first manned lunar landing on 20 July 1969. If played backwards, the words "small step for man" sound somewhat like "Man will space walk."

One explanation for this phenomenon is pareidolia, the tendency of the human brain to perceive meaningful patterns in random noise. Pareidolia is even more likely to occur when a person consciously tries to detect a pattern, as is the case for someone listening for intelligible phrases in backwards speech. The power of suggestion is then used to nudge the listener to hear what the presenter wants him to hear. David John Oates, for example, almost always tells the listener in advance what he should expect to hear, thereby planting a suggestion that would make the listener more likely to actually "hear" that phrase. A study has shown that when listening to the same clips without being told in advance what to expect, the results have a higher variation.

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