The Causes of Third-Person Effects: Unrealistic Optimism, Impersonal Impact, or Generalized Negative Attitudes Towards Media Influence?

The present study looks into the psychological origins of the third-person effect, i.e. the tendency of people to expect the media to be more effective on third persons than on themselves. Based on previous research literature, three different psychological mechanisms are distinguished that might cause the phenomenon. The concept of unrealistic optimism would predict that media effects described in a negative way will produce large third-person effects because individuals want to preserve a positive self. The same can be expected when subjects are described as passively suffering media effects. Empirically this means that the third-person effect will be smaller if media influences are described as a benefit, or the recipient suggested to be actively controlling the effects. The concept of impersonal impact suggests that the extent of the third-person effect varies with the psychological distance between the first and the third person. If third persons are described as psychologically close, the third-person effect will be smaller. The third concept of generalized negative attitudes towards media effects suggests that, regardless of the description, a third-person effect will always occur because negative predispositions to media influence are so strong that they cannot be overriden by variations in question wording. An experiment with 181 individuals produced mixed results. Depending on the kind of media effects, all three concepts can account for some of the results. The discussion centers around the question of whether different experimental designs could clarify the theoretical explanations, or whether third-person effects might be caused by combinations of psychological mechanisms rather than by only one such mechanism.