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](https://www.goodreads.com/book/show/686039.Subliminal_Seduction) 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)](https://doi.org/10.1037/0003-066X.40.11.1231) challenged the effect of subliminal messages in songs and a meta-analysis carried out by Charles [Trappey (1996)](https://ir.nctu.edu.tw/bitstream/11536/14246/1/A1996UZ40600005.pdf) 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)](https://books.google.co.uk/books/about/Psychology.html?id=-9x8dngFRe0C&redir_esc=y).

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?

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References
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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  
DOI: [10.1002/(SICI)1520-6793(199608)13:5<517::AID-MAR5>3.0.CO;2-C](http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1520-6793(199608)13:5%3C517::AID-MAR5%3E3.0.CO;2-C/abstract)  
**PDF Available FREE from [National Chiao Tung University](https://ir.nctu.edu.tw/bitstream/11536/14246/1/A1996UZ40600005.pdf)**

Vokey, J. R. & Read, J. D. (1985). *Subliminal messages: Between the devil and the media*, American Psychologist, 40(11): pp. 1231—1239  
PMID: [4083611](https://www.ncbi.nlm.nih.gov/pubmed/4083611) DOI: [10.1037/0003-066X.40.11.1231](https://doi.org/10.1037/0003-066X.40.11.1231)