What is subliminal effect?

The concept subliminal is archaic, although it is in daily use. The main problem is its necessary bound to the idea of a well-defined perceptual threshold, a concept now in disuse by the first appearance of the signal detection theory into cognitive sciences.

However, we'll remain to use this term, (so as the word "trance" in the field of hypnosis), due to the fact that it is deep-rooted in the minds of both public and the scientists . The isolated term means "below a threshold," however there is no clearly defined threshold to sensory perception. Indeed, there are many different perceptual features processed and detected before they are brought to our awareness, with the assistance of our attention. This makes the concept highly flexible in what and how we can integrate perceptual impressions into our awareness.

In scientific usage, we can call a stimulus subliminal only if it is faint enough, brief enough, or somehow cannot stimulate the senses enough to induce us to notice its presence, yet subsequent tests can register its presence. But, a more scientifically accurate word for this concept would be slightly perceptible.

The mainstream meaning of the word "subliminal" is any effect that influences our perception from outside of our awareness.

The interest in subliminal effects in modern science goes back to perceptual physiologist O. Poetzl in the first years of the 1900's. He studied the influence of flashed images on our dreams. In the 50's the introduction of the tachistoscope for even more fast flashing pictures provoked a renewed interest in subliminal effects. Originally a perceptual curiosity, it grew into both a public controversy and a research controversy.

The story of "subliminal effects" begins actually with the reports of a market research consultant: James Vicary. He affirmed that he could influence the behavior of movie audiences by flashing messages onto the screen. In a mood prepared carefully by the views of social critic Vance Packard, this assertion provoked an enduring and widespead fear of subliminal messages in the media. This fact evolved into a higher fear of embedded messages, movies, magazine pictures, of couse television, computer software, Muzak in stores and fear of backward played messages, considered satanis, in music songs.

V. Packard seems to have been concerned about the use of psychology by advertisers to produce symbolic messages in ads. This created some sources of fear, as the unceasing rumors of sexual symbolism in children's movies.
However, the story also has an offshoot. It is the moneymaking realm of tapes that are intended to help us program the mind without effort with self-help messages. A similar subliminal effect is claimed to help potential seducers win the minds and hearts of their quarry.

Subliminal is a term commonly used to actually mean several distinct types of hidden messages.

• Artistically or Blatant concealed messages suggestive of instinctual drives
• Images of contrived social exchanges and explicit body language
• Briefly or faint flashed images or words
• Metaphor or other "hypnotic" patterns
• Acoustically backward messages or masked in music songs

Of all these various types of "subliminal" effects, psychologists refer only to the flashed words or pictures, and the acoustic masking of a message, when they discuss about subliminal or marginal perception. All those are stimuli used in the subliminal experiments that cause weak, temporary psychological effects.
Putting it in other words, the scientific experimenters involved in research into subliminal priming agree that it do exists, however they are of the opinion that it consists of relatively fleeting and weak effects of mainly theoretical interest. This is probably true of unconscous lexical priming.

Several authors, specially Wilson B. Key, brought the word subliminal into public awareness. His literature is a clear warning that advertising companies are able of influencing their audience through hidden messages, or actively are doing so, with mainly malicious intent. His warning refers to what the psychologists call subliminal priming, however also a series of other types of persuasion tactics associated with the concept subliminal effect.

Following the main idea of Key, V. Packard and others in the same genre, the word subliminal is normally used to refer to influences on people that cannot be noticed. In addition to this weak stimulus used by researchers, it also includes elements like hidden images in scenes, the production of scenes for emotional motivation, playing songs backwards, metaphorical or embedded symbols in messages, the use of visual elements to invoke drives, and many more.

Whether all of these elements has an "unconscious" influence is rather a matter of empirical evidence, however whether there are effective influences is a matter or more investigation. Lumping all these elements together into a main category with faint and brief messages used in psychology experiments indeed makes it impossible to select things like social influence, emotional appeal, suggestion, preconscious processing, and associative conditioning.

Subliminal lexical priming is the influence of flashed words on subsequent words in a multiple choice test. It lasts about 90 milliseconds and it does not influence the next trial or the next experiments.

All subliminal lexical priming is the result of a flashed picture on basic preferences in a choice test, and it is more robust. This is known as the "simple exposure effect" . Some variations of the simple exposure effect have been proven to achieve emotional areas of the brain, specially the amygdala, without conscious awareness.

This is probably some kind of "classical conditioning" of feelings and memories without conscious awareness. It begins to enter into the area of something that can be produced into propaganda messages, especially if it is used as a reinforcer.
Subliminal psychological activations are one of the main methods, or at least the most intriguing. All subliminal stimuli enter into our dreams and waking pictures in a disturbed way, it influences later recalls and perceptions, and remarkably it even can influence our social acting. But, it is indeed the most difficult to prove, presumably because its main feature is that it is the most vulnerable to individual differences and the mental states of the recipients, besides the vagueries of individual interpretations of results.

The most efficient methods in practice imply both unconscious and conscious elements, both coordinated to appeal to emotions and exploit natural information processing way and common biases, as well as carry our unconscious thinking processes in a determined way.

Becoming somehow aware of subliminal effects generally reduces the influence of these, in both the exposure and psychological experiments. The whole combination of unconscious and conscious elements is carefully coordinated, however not duplicated (conscious elements are not transformed into unconscious).

The main reason why this methods is effective, compared to others relying or emphasizing on hidden pictorial messages, is due to the fact that hidden messages influence the feelings and thinking of test subjects, but they do not cause behavior, at least they don't do it by any known effect.

The subliminal influences behavior indirectly, principally by influencing perception, feeling and thinking . Conscious thinking triggers and organizes behavior, even though some aspects of behavior are not conscious, such as the main details of some movements or the expression of nonverbal communication.

Also hypnosis research has proven that compulsions and illusions can be created through simple suggestion under special conditions with particular people, without awareness of the source.

These hypnotic suggestions are highly limited by the main expectations of the test subject, the relationship stablished with the hypnotist, or the characteristics of the situation. The higher are the expectation, the more the subject can be controlled, or the greater their sense of practice the more involuntary they conduct their response.

It is the degree to which messages can produce a similar type of dissociated control that is at the main point of the most potential threat of subliminal persuasion. Without the expectancy factors that make suggestion effective, it is quite difficult to see how the comparison can be made.

Unless they are tailored to the individual, there is no evidence of any elaborate effect from preconscious processing of hidden messages, or that they are worth following as an aid to ads.

Achieving this type of effect through a combination of subliminal messaging and hypnotic means is a theoretical possibility under some conditions. At issue is the problem of creating the cooperative relationship needed for it, creating the expectancy that we can be controlled, and the differences in the way individuals respond to suggestion.

The threat of subliminal influence seems quite limited at this time due to the weak reinforcement of messages, however the combination of effects can be hard to determine. A message employing subliminal methods, like any one, can often have effects on the listener depending on their psychological needs and mind.