SUBLIMINAL MESSAGE
In common thinking subliminal learning is very often perceived as a mysterious and strange phenomena. Many people base their opinion on false premises, filling gaps in their knowledge with their own ideas and stories offered by pop culture. Perhaps that is how theories about almost magical possibilities of manipulating and controlling other people without them being aware of it emerge. There still exists a myth that subliminal influence on consumers choice of products is possible i.e. in when watching a movie in a cinema. Let us try to clarify what the term “subliminal” really means and what are the real possibilities connected with this phenomena.
Subliminal perception is just one form of unconscious perception (Underwood, 2004). Thus, subliminal learning is in fact just one way of implicit (unconscious) learning, the former being a much wider term.
The substantial difference between implicit learning and subliminal learning is the stimuli exposure time. A stimulation that is strong enough to activate sensory organs, but too weak to be consciously perceived is what we call a subliminal stimuli. Subliminal stimuli is then something that exists over the absolute perception threshold but below the consciousness threshold. Some researchers think (Marcel, 1983) that a stimuli can be considered to be a subliminal one even if it lasts long enough, on the condition that it appears in the peripheral attentional zone (it can be masked) or peripheral visual field (in the background).
There is also a distinction between a subjective and objective perception threshold. A subjective threshold marks the possibility of a conscious perception of a stimuli, while an objective threshold is a point where all discriminative reactions to a stimuli disappear. When a stimuli is presented close to the subjective threshold level it is possible to process it semantically, while on the objective level we can only process things in perceptional way (Dorfman et al., 2004).
Methodological problems are one of the biggest issues in the research of unconsciousness. It is very hard to study something that we are not aware of. How can we retrieve information that we have unconsciously acquired and are unconsciously storing? Frankly, we can not expect people to answer our questions if we are asking them about things they should not be aware of. That is why experimenters usually focus on the presence (or absence) of specific abilities. During an experiment participants are asked to perform a task requiring knowledge they are not aware of or define to be solved.
The most widely known phenomena in the context of subliminal learning is called priming. Priming effect occurs when exposure to a first stimulus (prime) influences processing of a subsequent stimulus (target). So the key issue is that the two stimuli get tied with each other sensorially or semantically. The nature of this relation determines the existence of many types of priming we can speak about (repetitive, semantic, peripheral etc.) Subliminal priming occurs when a prime is exposed for a very short period of time, usually from several to dozens milliseconds. Usually strict time relations between stimuli are kept.
The usage of subliminal techniques in marketing or advertisements is what perhaps rises the biggest controversy, because we are afraid that someone may try to force us to choose specific products and brands. How did it all begin? James Vicary used subliminal messages edited into a film in a cinema in New Jersey in the middle of the 20th century. It was an advertisement that was supposed to induce people to buy popcorn and coke. According to the experiment's author coke sales rose by 18% while popcorn sales went up by almost 58% (Aronson et al., 1997). Soon the results were questioned and logical mistakes in reasoning were found, and James Vicary later admitted that the whole study was a gimmick. But the gimmick turned out to be very inspiring and led other scientist to pursue their own studies on the issue. Even today, there are still products that are supposed to help us quit smoking, lose weight or improve our memory and performance by using subliminal messages.
In Greenswald's study (1991) two groups of people participated. Members of the first group listened to recordings with messages that were supposed to improve their memory, while recordings prepared for the second group were designed to improve self-assessment. Neither of the tapes had a significant effect on memory or self-assessment. But the important finding in this study was something else, because another experimental manipulation was made. Half of the participants in each group were actually listening to the tapes prepared for the other group. So, some of the persons listening to the memory enhancing tape were actually listening to the self-assessment improving recordings and vice-versa. It turned out, that when people thought that they are listening to a specific tape, they thought that this specific trait changed, regardless of the type of recording they were actually listening to. So, despite the fact that no actual change could be measured, people thought they changed, just because they believed the tapes work. Also, Neuberg's (1998) studies showed that subliminal messages can influence person's behavior only when somebody is already inclined towards such activities and when the message is in-line with the person's preferences.
It has been scientifically proved, that beyond any doubt awareness is not a necessary consequence of cognition, nor its necessary condition. Implicit, subliminal, or unconscious learning is definitely not something that could replace intentional and conscious learning, but perhaps it may boost it. Nevertheless, the door to influencing our own behavior with different kinds of subliminal exposures is still open...
Literature:
Dorfman, J., Shames, V.A. I Kihlstrom, J.F. (2004). Intuicja, inkubacja i wgląd: udział ukrytego poznania w rozwiązywaniu problemów. [W:] G. Underwood (red.) Poznawcza psychologia nieświadomości, Gdańsk. GWP.
Greenwald, A.G., Spangenberg, E.R., Pratkanis, A.R. I Eskenazi, J. (1991). Double-blind tests of subliminal self-help audiotapes. “Psychological Science”, 2, 119-122.
Marcel, A.J. (1983). Conscious and unconscious perception. An approach to the relation between phenomental experience and perceptual processes. Cognitive Psychology, 15, 238-300.
Murphy, Sh.T. i Zajonc, R.B. (1994). Afekt, poznanie i świadomość: rola afektywnych bodźców poprzedzających przy optymalnych i suboptymalnych ekspozycjach”. Przegląd psychologiczny, 37, 261-299.
Nęcka, E., Orzechowski, J., Szymura, B. (2006). Psychologia poznawcza. Warszawa. Wydawnictwo naukowe PWN.
Neuberg, S.L. (1988). Behavioral implications of information presented outside of awareness: The effect of subliminal presentation of trait information on behavior in the Prisoner’s Dilemma game. “Social Cognition”, 6, 207-230
Underwood, G. (1994). Subliminal perceptron on TV. Nature, 370,103.
