Prejudice is in all levels of education at home and take before any social stratum halt. Where they are liable they are no longer get rid of. Sometimes they are even passed on from one generation to the next and are old as the hills in this way. Two mechanisms are in the development and application “of prejudice into one another: The Selective Perception and generalize the trend. Man looking out to see what he wants, and the brain adapts to what is seen and experienced at the prejudice, rather than vice versa: a Bad parking woman pours the commonly held idea in concrete, and a hundred perfect indoor Parker can not change that.
A  social psychologist noted some years ago that prejudice also affect the victims themselves. In experiments, he found that blondes expect worse if you tell them before the test blonde jokes, and that men at lacking vocabulary when they are confronted in the experiment with this stereotype. In the driving simulator to put women in awkward, if they had previously indicated their gender.
An American research group made prejudices even visible: Using a magnetic resonance brain activities were measured by students, with photos of white and black men were shown. The brain activity in the prefrontal cortex, that brain area, are controlled in the environmental stimuli and were sorted, while in certain areas than in others. The pattern of these activities show, the interpretation of the researchers that the experimental participants at the sight Other colored tried to suppress existing prejudices.
What preconceptions and prejudices (researchers prefer to speak of “implicit association“), you have yourself, the Implicit Association Test (IAT out). This is verified, the speed with which people of certain positive and negative words an image (eg faces) or category (eg male / female associate). Simplified one can say: The stronger the association (the bias), the shorter the response time. It turns out that prejudice works both ways, and “sleepwalk” are nothing more than to positive introverted prejudice. Which again indicates that we have the prejudice against prejudice: Who from a “prejudice” speaks the word almost always used negatively.