Subliminal message is one of the tools of mind control. They seep into the unconscious through means undetected by the conscious mind and manipulate thought processes in a way that induces the individual to behave in a manner contrary to his original plans. The process of getting inside the mind and controlling thoughts have kept philosophers, scientists, corporate agencies and general public equally enthralled.

Subliminal messages operate through the subconscious which is supposed to be more complex than the conscious cognitive faculties. The relation between conscious and the subconscious have been explored in the writings of Johan Friedrich Herbart. He refers to ?limen of consciousness?, the interspersing boundaries of the conscious and the subconscious, where ideas battle for supremacy. According to him, ideas lie below the level of consciousness and compete with each other to enter the realm of consciousness. In this process they also influenced each other. So, the ideas that hover just below the level of consciousness still have the power to influence the conscious mind. This is where subliminal messages come into play.

Many psychologists reject the idea of the separate existence of the conscious and the subconscious. They divide the cognitive processes into two different ?threshold? of awareness, subjective and objective. Here the cognitive agencies respond to the presence or absence of stimulus. Any event which lies below the subject's subjective threshold and simultaneously above the subject's objective threshold then it would be considered to be a subliminal influence.

One of the questions that have kept scientists busy is how much of subliminal messages are perceived by the brain. Some believe that only the easiest part of the subliminal messages is absorbed. Some believe that the subconscious is much more receptive and absorbs more than can be expressed in words. Recent research conducted by University College London show that subliminal messages do capture cerebral attention on a subconscious level. The effect of that on conscious decision making is not clear but it is certainly an interesting development.

Subliminal messages use audio visual medium to reach inside a person's mind. Since 5th century B.C. used language to manipulate human psyche. Nowadays subliminal tools have become more sophisticated. Self-hypnosis is one of the most popular subliminal tools used to enhance self confidence and concentration. Backmasking is another method that is believed to be used through music to transmit subliminal messages. Corporate agencies used mind control techniques to induce purchases. None of the above mentioned techniques and theories has been validated by scientific evidence.