The Psychology Department of the University of Michigan indicates that the word subliminal is the result of the union of two words in Latin: sub (below) and limen (threshold). Thus, the literal meaning of the word subliminal would be "below the threshold”. At first glance the definition of subliminal is simple, however, what do psychologists understand by threshold?According to this same institution (based on experiments performed in this field by Schmeidlerand other psychologists), the threshold is the point at which a stimulus is perceived 50% of the time, understanding perception  as the process through which an individual is able to organize (organization) different inputs (stimulation) that receives through his senses (registration), in order to obtain a final output based on his needs (interpretation).On this basis, we can specify that when an input is perceived or interpreted unconsciously, this input is equivalent to what today is known as "subliminal message”.
The concept of "subliminal message" has been present since ancient times (for example rhetoric usage in the 5th century BC), but it was not until 1957 when it was made public through the book "The Hidden Persuaders“ written by Vance Packard.In this book Packard says : “ Large-scale efforts are being made, often with impressive success, to channel our unthinking habits, or purchasing decisions, and our thought processes….Typically these efforts take place beneath our level of awareness; so that the appeals which move us are often, in a sense, hidden.” Thelivelihood of this bock istheexperimentperformedbytheresearcher James Vicary, whoclaimedtohavecreated a machine capable of flashing "subliminalmessages“ inscreenmovies. Using this machine, he flashed the messages "Hungry? Eat Popcorn" and "Drink Coca-Cola" in brief intervals of time while projecting the movie "Picnic". According to Vicary, the results of this experiment were traduced in an increase of 57.8% and 18.1%in popcornandCoca-Cola sales respectively. 
Subliminal messages and subliminal perception are strongly related. The concept of subliminal perception holds that subliminal stimuli or messages are perceived by the individual without being aware of it, ie below the threshold, influencing the behavior relatedto his feelings, thoughts or actions.  It is important not to confuse the lack of awareness with the lack of attention, since, as mentioned by CO Evans & J. Fudjac in their study, only when attention is present subliminal perception can occur. Although the researchdoes not support it, it is common to find statements claiming a great power of influence of subliminal perceptions, even over the conscious perceptions that the individual may have. At the same time, there is no basis conclusively evidencing the influence of subliminal perceptionin the execution of certain actions  . In order to do that, it is necessary some level of consciousness to make decisions .There are two types of subliminal perception: visual and aural. The typography of this perception is directly related to the type of message or stimulus that is emitted. 
A term widely used in psychology when discussing visualsubliminal perception is the word priming. Priming is understood as the "process of activating a mental representation and its connections to memory in relation to a perceived stimulus”. Visual subliminal messages act as prime with the aim of speeding up the connections. Its effects have been proved in several research and they basically depend on the necessity the individual has in relation to the subject in question (goal-relevant) .Visual subliminal messages can be represented, for example, by words, videos or graphics.Priming used in Marketing, commonly is the pairing of a message with images and colors that invoke a positive response. For example, a brand image paired with happy music, bright colors, and pleasant images will provoke a positive emotional response from the viewer, so when he sees the product in the store, he remembers the positive emotional response.
Egermann, Kopiez and Reuter, mention in their research  different ways to incorporate a subliminal worded message in music, being the main ones:Placing the message at levels below the auditory threshold and masking it with musicUsing “backward masked messages” or, what is the same, words with an inverted-time structureUsing “silent-subliminals”, which are highpass-filtered worded messages that contain frequencies above 15 kHzHiding in the music time-shrunk subliminal messages (messages played back twice as fast as recorded)In a 2005 study, researchers Sid Kouider and Emmanuel Dupouxfound that priming does have a significant effect and that effect becomes stronger the more often the message is repeated. Further, the effect is consistent, regardless of a change in the speaker's voice.
As mentioned at thebeginning, theprocess of perceptionrequiresthe prior existence of somestimuli. Onthisbasis, we can saythat subliminal perceptionrespondstostimuli of thesamenature, which are presented in differentways. The most common subliminal stimulationtechniques are:Masking: presentation of a stimulus "A", of short duration, followed by the presentation of a stimulus "B" of longer duration.Direct impoverished stimulation: stimulation below the conscious level with subsequent execution of a specific task to test the effectiveness of the stimulus. a) Tachistoscopic Displays: are where many images are flashed by the subject at high speeds. Most viewers cannot consciously view the imagery before the next one appears and therefore absorb them all into subconscious memory. Tachistocscopes were originally developed to test subliminal images and flashed images at 1/3000 second. Recess: Insertion of a stimulus (ie: word) in a complex context (ie: photography) in order to camouflage it within supraliminal perception. Also known as “Embedding” or the process by which one image on icon is worked into or around another as to make the image being advertised stand out while the secondary image is ignored and remembered unconsciously. In embedded pictures, nothing is actually hidden. Dichotic stimulation: simultaneous presentation of subliminal and supraliminal stimuli.Double Entrance: is a form of subliminal in which the main focus of the ad has a double meaning and the secondary meaning is the one related of the message intention.
Subliminal messages fv
SUBLIMINAL PERCEPTION<br />By<br />Melissa Arbulú & Daniel Agosin<br />
Subliminal Perception<br />Auditory Subliminal Perception<br />Target messageis placed belowtheauditorythreshold and ismaskedbymusic<br />Possibleto use “backwardmaskedmessages”<br />Possibleto use “silent-subliminals”<br />Time-shrunk subliminal messages can be hidden in music<br />Subliminal Perception<br />04/10/2011<br />
Subliminal Stimulation – Techniques<br />1970's by illustrator, Nelson Carrick<br />Subliminal Perception<br />04/10/2011<br />
Subliminal Messaging – Effectiveness?<br />Weight loss messages, smoking cessation, assertiveness cues, back masking in music, self-esteem and memory in audio tapes, and embedded pictures are ineffective <br />Recent studies demonstrate that subliminal priming can, indeed, be perceived unconsciously (i.e., Lipton Ice), and only works when the prime goal is goal-relevant.<br />Subliminal Perception<br />04/10/2011<br />
There is no conclusive research evidence that subliminal stimulation & advertising works<br />ITWORKS<br />
ApplicationExamples: Advertisment<br />A brief, specific message that cannot be <br />perceived at a normal level of conscious <br />to influence the costumer behavior<br />SUBLIMINAL<br />ADS.<br />≠<br />Placement & Associative ads.<br />Subliminal Perception<br />04/10/2011<br />
Conclusions<br />The main purpose of subliminal messages:induce people's behavior through unconscious perception.<br />Although their effectiveness has not been fully tested due to its nature, it can be said that this is closely related on whether subliminal messages are goal-relevant to the person or not.<br />The potential impact that these messages have on the consumer ‘s behavior, despite the controversy they generate, promote the extensive use of them in<br />advertising.<br /> Is it an ethical practice for businesses to use and develop SM? Just a clue: According to AMA’S code of ethics, the marketers: Must “represent intentions transparently”.<br />Subliminal Perception<br />04/10/2011<br />
References<br />Reference  University of Michigan, Psychology Department http://www.umich.edu/~onebook/pages/tablepages/psych.html<br />Reference  “Psychology oh Human Behavior” - KUMAR, Arvind<br />Reference  “Unconscious Processing: Subliminal Perception, Neuropsychology, and the I-Function” -HELLEW, Lauren http://serendip.brynmawr.edu/bb/neuro/neuro99/web2/Hellew.html and “MPRA”- KLIMOV, Blagoy<br />Reference  MERIKLE, Phillip - University of Waterloo, Psychology Department http://watarts.uwaterloo.ca/~pmerikle/papers/SubliminalPerception.html<br />Reference  “Consciousness” – EVANS, C.O and FUDJAC´S, J. http://www.subliminal-message.info/subliminal_research.htm<br />Reference [6 ] MERIKLE, Phillip - University of Waterloo, Psychology Department http://watarts.uwaterloo.ca/~pmerikle/papers/SubliminalPerception.html<br />Reference  “Unconscious Processing: Subliminal Perception, Neuropsychology, and the I-Function” -HELLEW, Lauren http://serendip.brynmawr.edu/bb/neuro/neuro99/web2/Hellew.html<br />Reference  University of Michigan, Psychology Department http://www.umich.edu/~onebook/pages/tablepages/psych.html<br />Reference  “Is there an effect of subliminal messages in music on choice behavior? “ EGERMANN, Hauke ; KOPIEZ, Reinhard and REUTER, Cristoph<br />Reference  “Is there an effect of subliminal messages in music on choice behavior? “ EGERMANN, Hauke ; KOPIEZ, Reinhard and REUTER, Cristoph<br />Reference : http://www.unicog.org/biblio/Author/KOUIDER-S.html<br />Reference : Zachary Jones , Sauer, 11/21/96. http://eserver.org/courses/fall96/76-100g/zcj/<br />Reference : Benady, David // Marketing Week (01419285); 9/25/2003, Vol. 26 Issue 39, p14 <br />Reference : http://www.unicog.org/biblio/Author/KOUIDER-S.html (Cerebral bases of subliminal speech priming)<br />Reference :<br /><ul><li>Simpson, P., Brown, G., & Widing, R. E. (1998). The association of ethical judgment of advertising and selected advertising effectiveness response variables. Journal of Business Ethics, 77(2), 125-136.
Rogers, M., Seiler, C. A. (1994, March/April). The answer is no: A national survey of advertising industry practitioners and their clients about whether they use subliminal advertising. Journal of Advertising Research, 34(2), 36-45.</li></ul>Subliminal Perception<br />04/10/2011<br />
Reference : Wells, William, Burnett, John & Moriarty, Sandra (1996): Publicidad, principios y prácticas. Terceraedición. México. Prentice-Hall.
Reference : Singh Garodia, Vikram (2011) “Effect of subliminal messages on the sales of a product”. Case of: slice “aamsutrapunjab technical university. New delhi institution of management.</li></ul>OTHERS<br /><ul><li>http://www.cbc.ca/news/canada/story/2007/02/25/video-lottery.html