Subliminal Perception and Hidden Messages

Psychology 101: The 101 Ideas, Concepts and Theories that Have Shaped Our World - Adrian Furnham 2021

Subliminal Perception and Hidden Messages

Our mind is so fortunately equipped, that it brings us the most important bases for our thoughts without our having the least knowledge of this work of elaboration. Only the results of it become unconscious. (W. Wundt, The Unconscious before Freud, 1960)

Consciousness reigns but does not govern. (Paul Valery, A Certain World, 1970)

Nearly 50 years ago an American writer called Vance Packard argued that by using subliminal cues, advertisers and marketers persuaded people to buy against their will. These cues could be very short, imperceptible visual or verbal messages that people claimed not to see or hear.

Packard said that ordinary people were being cynically manipulated by advertisers who were using underhand techniques to persuade people to buy their products. But, of course, the technology could be used by religious or political bodies to sway opinion their way. The theory is that people can be emotionally and behaviourally affected by visual or vocal stimuli whose presence they do not report. They are receiving hidden messages.

Whether it is called preconscious processing or unconscious perception, few psychologists dispute or would even be surprised by the idea that people can be affected by stimuli they claim not to have seen. What people say they saw and did see are not the same.

By flashing up images and words very quickly, scientists have been able to demonstrate reliably the process called subliminal perception. But, and it is a very big but, there is very little evidence that subliminal perception then systematically and consistently influences a person’s attitudes, beliefs, choices and motives. There is, in short, little or no reliable scientific evidence that subliminal perception has any behavioural impact or long-term effect on intentions or consumer behaviour. In this sense you need not be worried about the power of subliminal messages in advertising.

But lack of evidence has never got in the way of a good theory. So down the years journalists and popular authors have argued that some, even most advertisements, contain hidden sexual images or particular brand names or messages that affect our susceptibility to those advertisements.

The attention-grabbing, paranoid, but evidence-free myth goes: clever (wicked) advertisers can make you do things against your better judgement, conscious decision-making or will, by subliminal messages in (mainly television, but also radio) ads. Careful research has however suggested, as one reviewer put it, this idea is absurd or laughable and ludicrous, paranoid and preposterous.

We know that advertisements use visual or vocal words or themes to encourage us to make connections between brands, products and particular behaviours and emotions. We also know that advertisements may well influence attitudes and values without people’s awareness. But this is not subliminal advertising.

From the late 50s to the mid-70s books with titles like Subliminal Seduction and Media Sexploitation kept the notion alive for a public apparently happy to see wicked manipulative scientists working with greedy, cynical advertisers. Shopaholism, suicides and sexual disorders were all seen to be partly consequences of this conspiracy. But the evidence was lacking.

However, clever salesmen did see the positive side of the public’s gullibility. They knew from their research that subliminal advertising did not work…and was anyway both illegal and illogical. But why not turn the whole thing around and openly sell the technique? Hey presto! We have subliminal auditory self-help tapes.

Soon recordings were on sale that supposedly showed dramatic changes in mental and psychological health. You simply set the recording to go off while you were asleep and you could experience weight-loss, improved sexual function and ease in stopping smoking, nail-biting or fear of flying. These recordings came in various forms. Some were designed to be played while awake. But they all had those subliminally embedded messages that you could not pick up but which could change your life. Cynics of course said if you could not hear the message how do you know if they even existed?

The modality changed from visual to auditory and the image of the science from wicked to helpful. Scientists got to work on this one, testing the claim that an undetectable speech signal changes any form of behaviour. It is a stronger claim that if critical messages are masked (drowned or washed out) by other sounds, the weak becomes detected, then disentangled and then comprehensible.

These recordings supposedly provide a pipeline to the Id — that Freudian concept of the primitive persona which is a cauldron of seething excitement. They can, it is claimed, get to the deepest parts of our being, our primitive, unknowable, secret self.

The scientists have tested these assumptions carefully. The jury is back. There is no evidence for most of these theoretically jumbled claims. This is therefore not only quackery but fraud: the advertisements have the obvious intention to deceive people who want a fast, cheap ’cure’ involving little willpower or pain.

Scientists might be unanimous in their evidence-based opinion that subliminal recordings make fraudulent claims, but they don’t seem too hot at getting their message across.

On the other hand, the commercially savvy tape-producers have commissioned advertising agencies to design new campaigns. Using scientific jargon and imagery and the power of repetition, the aggressive campaigns have succeeded in keeping the myths alive. It is ironic that traditional advertising succeeds in selling subliminal recordings that don’t persuade.

Advertisers and marketing people are clever and resourceful. They know how to manipulate our mood which can influence our behaviour while shopping. They do their best to make us recall their brand and have positive associations with it. And they are now turning to ’brain science’ to make them even more successful. The hope for many is to find those ’hidden persuaders’ that may actually work this time.


Dixon, N.F. (1971). Subliminal Perception: The Nature of a Controversy. London: McGraw-Hill.

Dixon, N.F. (1981). Preconscious Processing. Chichester: Wiley.

Nelson, M.T. (2008). The Hidden Persuaders: Then and Now. Journal of Advertising, 37, no. 1.