Mere-exposure effect

The mere-exposure effect is a psychological phenomenon by which people tend to develop a preference for things merely because they are familiar with them. In social psychology, this effect is sometimes called the familiarity principle. The effect has been demonstrated with many kinds of things, including words, Chinese characters, paintings, pictures of faces, geometric figures, and sounds. In studies of interpersonal attraction, the more often a person is seen by someone, the more pleasing and likeable that person appears to be.

The earliest known research on the effect was conducted by Gustav Fechner in 1876.Edward B. Titchener also documented the effect and described the "glow of warmth" felt in the presence of something that is familiar. However, Titchener's hypothesis was thrown out once tested and results showed that the enhancement of preferences for objects did not depend on the individual's subjective impressions of how familiar the objects were. The rejection of Titchener's hypothesis spurred further research and the development of current theory.

The scholar who is best known for developing the mere-exposure effect is Robert Zajonc. Before conducting his research, he observed that exposure to a novel stimulus initially elicits a fear/avoidance response by all organisms. Each repeated exposure to the novel stimulus causes less fear and more of an approach tactic by the observing organism. After repeated exposure, the observing organism will begin to react fondly to the once novel stimulus. This observation led to the research and development of the mere-exposure effect.

In the 1960s, a series of laboratory experiments by Robert Zajonc demonstrated that simply exposing subjects to a familiar stimulus led them to rate it more positively than other, similar stimuli which had not been presented. In the beginning of his research, Zajonc looked at language and the frequency of words used. He found that overall positive words received more usage than their negative counterparts. In later years, he moved on to show similar results for a variety of stimuli such as polygons, drawings, photographs of expressions, nonsense words, and idiographs, as well as when being judged by a variety of procedures such as liking, pleasantness, and forced-choice measures.

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