The basis of this selectivity lies in variations in habits of perception among members of society.
Variations in habits of perception occur because each individual has a unique personal organization of beliefs, attitude, values, needs and modes of experiencing gratifications that have been acquired through learning.
Because perception is selective, interpretation, retention and response to media messages are selective and variable.
Thus, the effects of the media are not uniform, powerful or direct--they are selective.
Presentation on Limited Effects Theory
For example, a violent TV program probably will not incite all of its viewers to go out and commit mayhem, but it may reinforce the already existing violent tendencies of a small sample of the viewers and slightly dull the sensitivities of many others. Certain positive and negative aspects of media may affect exceptional children more than normal children.
A major effort of this type of research has been to discover other interactive variables that mediate or moderate the effects. These may be demographic variables classifying the individual (gender, ethnicity, age) or they may be properties of the message or of the context of its reception. Taken together, these interactive variables may be considered risk factors; the effects will be stronger in relation to the greater number of risk factors of a particular person. The fact that the effects are not uniform does not denigrate their importance.
Joseph Klapper, a critic of the theory of uniform effects,
believed mass communication did not directly influence people,
but reinforced their predispositions
Even though a given effect occurs in only 0.01% of the viewers of a certain TV program, that still has an impact on 4,000 people out of an audience of 40 million.