| MadSci Network: Neuroscience |
Mike,
I think I'm going to give you more information than you wanted. I can find more information to support the 'null hypothesis' (that there is no effect of subliminal messages) than to support the hypothesis that subliminal messages have an effect on people's actions; and I myself accept the null hypothesis. I found a discussion of the null effect at a website called "Quackwatch" (http://www.quackwatch.com/index.html). The article is included below because it was hard to find. Something purporting to be a CIA report on subliminal messages is at http://www.parascope.com/articles/0397/sublim.htm.
Although I found some commercial sites for subliminal learning (http://www.infinn.com/subliminal.html and http://www.subdyn.com) they did not provide any proof of the effectiveness of these products, but they may have something you can use in a science experiment. The page http://www.poleshift.org/sublim/ states that "Subliminal advertising. . . is based on the fact that under any circumstances, you store more information in a fraction of a second--and are influenced by it--than you are ever consciously aware of." The problem with this sentence is the use of the word "fact" instead of "idea". People are fascinated by the idea that their behavior can be influenced without their knowing. This idea has not been well supported. The ideas discussed by Michael Robbins (at poleshift) seem to confuse attention with subliminal behavior modification. I do not disagree that advertisers use unstated messages to sell products - otherwise everyone in advertisements would not be so healthy looking! But this is not the same as what is referred to as subliminal, that is "not recognized or understood by the conscious mind, but still having an influence on it" (Cambridge dictionary).
Thinking of a test you could design is difficult, as I do not know what equipment is available to you. The 'sublminal message' should not be recognized by the conscious mind. Most experiments present subliminal stimuli for a very short period of time - something that you may not be able to do. Perhaps you could make a very short tape which you could ask someone else to play while they were asleep - but if they heard it when they were awake then the message would not be sublminal. If you accept Robbins' definition of subliminal, then you might try using the methods used by Andrew Aylesworth and colleagues in the papaer "Effect of archetypal embeds on feelings: An indirect route to affecting attitudes?", Journal of Advertising, 1999, Fall; Vol 28(3): pages 73-81.
They examined how exposure to a type of image in ads affected viewers' feelings and thoughts about the products. You could select four similar advertisements from magazines, two of which had a particular type of image (you pick what type you want to look at) and two of which did not. Ask people to look at the ads and answer some questions. Make sure the questions are NOT about the particular type of image you selected, and don't tell the people anything about the images. Instead, ask questions like, how energetic do you feel when you look at this advertisment? (You can use a scale of 0 to 10, where 0 is not energetic and 10 is very energetic). Or how happy do you feel, or how upset do you feel. You can ask, how likely would you be to buy this product? Then, see if the answers are different for the two ads with the particular type of image you selected than for the two ads without it.
One last comment: most of the pages I looked at took an extremist view - either subliminal learning was the absolute truth or total falsehood. This concerns me, because neither extreme view gives a balanced picture, and trying to understand something by contrasting extreme views can be very confusing. Good luck with your science project, and feel free to contact me if you need any other assistance: lynn.nielsen- bohlman@mcmail.vanderbilt.edu
Included Article Below:
Questionable "Self-Help" Products Many tapes have been marketed with
claims that they inspire people to function better mentally, improve
relationships with others, relieve anxiety or depression, or achieve
other desirable emotion-related goals. Gerald Rosen, Ph.D., former
chairman of the American Psychological Association's Task Force on
Self-Help Therapies, has noted that "Although some of these materials
may be helpful, most have not been tested for validity. Many
self-help materials are promoted with extravagant and ethically
questionable claims."
Subliminal Tapes Thousands of videotapes and audiotapes purported to
contain repeated messages are being marketed with claims that they can
help people: lose weight, stop smoking, enhance athletic performance,
quit drinking, think creatively, raise IQ, make friends, reduce pain,
improve vision, restore hearing, cure acne, conquer fears, read
faster, speak effectively, handle criticism, relieve depression,
enlarge breasts, and do many other things. At least one company has
offered subliminal tapes for children, including a toilet-training
tape for toddlers. Many tapes contain music said to promote
relaxation. Most are claimed to contain messages that are inaudible or
barely audible, but some are barely or fully audible. Videotapes may
feature images, said to be relaxing, combined with repeated visual
messages shown so briefly that they cannot be seen at normal playing
speed.
Many researchers have found that subliminal tapes provide no benefit
to the user. One who tested tapes from several companies concluded
that they contained no embedded messages that could conceivably
influence behavior [1]. A research team tested volunteers for a study
of tapes said to improve memory and self-esteem, but switched the
tapes for half of the participants (to create a control
group). Regardless of the tape used, about half of the volunteers
claimed to achieve the results they were told to expect-but objective
tests of memory and self-esteem showed no change [2]. A National
Research Council committee has concluded that although many people
claim that subliminal self-help tapes contribute to self-improvement,
there is no scientific evidence to support such claims [3]. Thus there
is no reason to believe that musical tapes with subliminal messages
can do anything more for physical or mental well-being than listening
to ordinary music. There is no scientific evidence that messages which
cannot be heard are unconsciously or subconsciously perceived or can
influence behavior [4].
References
1.Merikle PM. Subliminal auditory messages: An evaluation. Psychology
and Marketing 5:355-372, 1989.
2.Greenwald AG, Spangenberg ER, Pratkanis AR. Double-blind tests of
subliminal self-help audiotapes. Psychological Science
2:119-122, 1991.
3.Bjork RA and others. In the Mind's Eye. Enhancing Human Performance.
Washington D.C., 1991, National Academy Press.
4.Moore TE. Subliminal perception: Facts and fallacies. Skeptical
Inquirer 16:273-281, 1992.
Portions of this article appeared in the 6th edition of Consumer Health: A
Guide to Intelligent Decisions. This article was revised on August 5,
1998.
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