That something is subliminal means that it is perceived by the brain, but not of consciousness. Subliminal effect is therefore influence the limits of what humans are able to perceive. The idea has been piloted in the advertising industry to induce consumers to take up the "hidden" messages.
It's the classic experiment of such effects is a film performance, in which the text "Drink Coca-Cola!" exposed on the screen several times, but in such a short time that viewers did not he understand this. The total beverage sales grew during the show and Coca-Cola sales the most. The conclusions one can draw from this is unfortunately uncertain, because other advertising for the drink was in the same film.
Other attempts in the same idea has been to expose parts of the journals to study the scanning behavior of subjects relative to normal scanning. It has been found that the exposed parts in magazines tend to attract the eye, no matter where the parts were retrieved.
We therefore claim that subliminal influence is quite feasible. But this would be more effective than traditional advertising is unlikely. With the methods used so far seems to result rather be significantly worse.