Definition
sub- limen
Subliminal is a two part word consisting of the prefix sub- and the root word limen. Sub- means below and limen (Greek) means threshold. Thus subliminal comes to mean below threshold. But what is a threshold?
threshold
According to Schmed, and the vast majority of psychologists studying subliminal phenomena, a threshold is the point at which a stimulus is perceived 50% of the time. For example, if my aural threshold were to be tested, I would be played numerous sounds in varying volumes. To signal that I heard the tone—I perceived the stimulus—I would raise my hand or press a button, whatever the researches had instructed me to do when I hear a sound. By controlling and tracking the frequency of the emitted sound, the researchers are able to find the volume at which I hear a sound—perceive the stimulus—half of the time. This point is my auditory threshold.
Conflicts
thresholds
Though a working definition of threshold is necessary before any research can be conducted on subliminal messages,
Thresholds not only allow for research on subliminal messages, they also confuse the matter. Though defined in a professional and statistical manner, there are several pertinent details concerning thresholds making research even more difficult:
Already known from other areas of research is the fact that we do receive information in our lower brain that never makes it to the cortex. The cortex is where things are “made conscious”. This is where sensory perception comes in to play. “We are a walking mass of thresholds.” It is estimated that for every 1,000,000 stimuli that pass by the sensory threshold, 1 stimulus passes through the perceptual threshold. This is how the intricacies of human behavior are explained. Humans simply do too much to be conscious of it all.
Vary day by day, person by person
1. Not only do thresholds vary from person to person, but they also vary day by day within one person. So what I can’t hear today I may hear tomorrow and vice versa. It is quite plausible that these variances are accounted for in the statistical analysis. There are safety features, if you will, built into the processing of data (one example being “statistical significance”)
Threshold becomes ‘perceptual threshold’
2. Psychologists have more or less massaged the theory of thresholds so that subliminal messages could “exist” and be “studied”. By this I mean that there has been a distinctive breaking of threshold into two parts: sensory threshold and perceptual threshold. It is the perceptual threshold that is utilized in the realm of subliminal messages.