Throughout the history of the study of media effects, researches have been interested in the effects of political communication. As you have learned in earlier chapter, findinds on the power of mass-mediated effects have varied through the years, and political communication effects are no exception. Studies of voting behavior in the 1940s and 1950s indicated that mass-mediated political communication effects were rather limited. In these well-known studies, mass media were found to influence opinion leaders, who in turn influenced others through interpersonal communication. Later studies have put into question the integrity of the limited effects model by presenting findings of more direct and powerful media influence on voters from political campaign messages. For example, Noelle-Neumann's Spiral of silence theory suggests powerful effects result whenever people fear social alienation or isolation enough to keep quiet and not speak their views.