The idea of being able to influence somebody without them consciously knowing is undoubtedly intriguing.
"The two most famous types of alleged subliminal messages are:
- Spoken messages which are recorded backward onto a track that is meant to be played forward, called backmasking
- Written messages which are quickly flashed during videos, sometimes called 25th frame"
"Used in advertising to create familiarity with new products, subliminal messages make familiarity into a preference for the new products. Johan Karremans suggests that subliminal messages have an effect when the messages are goal-relevant. Karremans did a study assessing whether subliminal priming of a brand name of a drink would affect a person’s choice of drink, and whether this effect is caused by the individual’s feelings of being thirsty.
His study sought to ascertain whether or not subliminally priming or preparing the participant with text or an image without being aware of it would make the partaker more familiar with the product. Half of his participants were subliminally primed with Lipton Ice ("Lipton Ice" was repeatedly flashed on a computer screen for 24 milliseconds), while the other half was primed with a control that did not consist of a brand. In his study he found that subliminally priming a brand name of a drink (Lipton Ice) made those who were thirsty want the Lipton Ice. Those who were not thirsty, however, were not influenced by the subliminal message since their goal was not to quench their thirst.
Subconscious stimulus by single words is well known to be modestly effective in changing human behavior or emotions. This is evident by a pictorial advertisement that portrays four different types of rum. The phrase "U Buy" was embedded somewhere, backwards in the picture. A study (Key, 1973) was done to test the effectiveness of the alcohol ad. Before the study, participants were able to try to identify any hidden message in the ad, none found any. In the end, the study showed 80% of the subjects unconsciously perceived the backward message, meaning they showed a preference for that particular rum. Though many things can be perceived from subliminal messages, only a couple words or a single image of unconscious signals can be internalized. As only a word or image can be effectively perceived, the simpler features of that image or word will cause a change in behavior (i.e., beef is related to hunger). This was demonstrated by Byrne in 1959. The word "beef" was flashed for several, five millisecond intervals during a sixteen-minute movie to experimental subjects, while nothing was flashed to controlled subjects. Neither the experimental nor controlled subjects reported for a higher preference for beef sandwiches when given a list of five different foods, but the experimental subjects did rate themselves as hungrier than the controlled subjects when given a survey. If the subjects were flashed a whole sentence, the words would not be perceived and no effect would be expected.
In 2007, to mark the 50th anniversary of James Vicary's original experiment, it was recreated at the International Brand Marketing Conference MARKA 2007. As part of the "Hypnosis, subconscious triggers and branding" presentation 1,400 delegates watched part the opening credits of the film PICNIC that was used in the original experiment. They were exposed to 30 subliminal cuts over a 90 second period. When asked to choose one of two brands 81% of the delegates picked the brand suggested by the subliminal cuts.
Studies in 2004 and 2006 showed that subliminal exposure to images of frightened faces or faces of people from another race will increase the activity of the amygdala in the brain and also increase skin conductance.
In 2007, it was shown that subliminal exposure to the Israeli flag had a moderating effect on the political opinions and voting behaviors of Israeli volunteers. This effect was not present when a jumbled picture of the flag was subliminally shown. "