I certainly don't question the existence of subliminal perception which has been demonstrated many times in priming studies like those of Daniel Schacter and many others, nor do I reject the notion of the cognitive unconscious introduced by Kihlstrom (I definitely have my doubts on the psychodynamic unconscious however).
My question is about certain big claims like those of Bryan Wilson Key on subliminal messages with sexual content and consumer behaviour, those about subliminal self-help tapes or those even more suspicious that are about subliminal messages detering shoplifters to steal. Other than null results or junk science I haven't seen any convincing study supporting these claims.
On the other hand, studies by Vockey and Read (1985) challenged the effect of subliminal messages in songs and a meta-analysis carried out by Charles Trappey (1996) showed a negligible effect on consumer behavior. Also, what I get from most psychology textbooks is that the general consensus is that subliminal messaging has a poor and temporary effect (Schacter, Gilbert and Wegner, 2009).
Of course, one has to consider if subliminal perception is qualitatively and quantitatively different depending on the modality of the stimuli but then again I am unconvinced of a considerable effect of subliminal messaging on behaviour.
Any thoughts on that?
Schacter, D. L., Gilbert, D. T. & Wegner, D. M. (2009). Psychology. New York, NY: Worth Publishers
Trappey, C. (1996). A meta-analysis of consumer choice and subliminal advertising, Psychology & Marketing, 13(5): pp. 517—530
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