Hypodermic needle model
||This article needs additional citations for verification. (July 2009)|
The hypodermic needle model (also known as the hypodermic-syringe model, transmission-belt model, or magic bullet theory) is a model of communications suggesting that an intended message is directly received and wholly accepted by the receiver. The model is rooted in 1930s behaviorism and is largely considered obsolete today.
The "Magic Bullet" or "Hypodermic Needle Theory" of direct influence effects was not as widely accepted by scholars as many books on mass communication indicate. The magic bullet theory was not based on empirical findings from research but rather on assumptions of the time about human nature. People were assumed to be "uniformly controlled by their biologically based 'instincts' and that they react more or less uniformly to whatever 'stimuli' came along" (Lowery & De Fleur, 1995, p. 400). The "Magic Bullet" theory graphically assumes that the media's message is a bullet fired from the "media gun" into the viewer's "head" (Berger 1995). Similarly, the "Hypodermic Needle Model" uses the same idea of the "shooting" paradigm. It suggests that the media injects its messages straight into the passive audience (Croteau, Hoynes 1997). This passive audience is immediately affected by these messages. The public essentially cannot escape from the media's influence, and is therefore considered a "sitting duck" (Croteau, Hoynes 1997). Both models suggest that the public is vulnerable to the messages shot at them because of the limited communication tools and the studies of the media's effects on the masses at the time (Davis, Baron 1981).
Later developments 
The phrasing "hypodermic needle" is meant to give a mental image of the direct, strategic, and planned infusion of a message into an individual. But as research methodology became more highly developed, it became apparent that the media had selective influences on people.
The most famous incident often cited as an example for the hypodermic needle model was the 1938 broadcast of The War of the Worlds and the subsequent reaction of widespread panic among its American mass audience. However, this incident actually sparked the research movement, led by Paul Lazarsfeld and Herta Herzog, that would disprove the magic bullet or hypodermic needle theory, as Hadley Cantril managed to show that reactions to the broadcast were, in fact, diverse, and were largely determined by situational and attitudinal attributes of the listeners.
Lazarsfeld disproved the "Magic Bullet" theory and "Hypodermic Needle Model Theory" through elections studies in "The People's Choice" (Lazarsfeld, Berelson, Gaudet 1944/1968). Lazarsfeld and colleagues executed the study by gathering research during the election of Franklin D. Roosevelt in 1940. The study was conducted to determine voting patterns and the relationship between the media and political power. Lazarsfeld discovered that the majority of the public remained unfazed by propaganda surrounding Roosevelt's campaign. Instead, interpersonal outlets proved more influential than the media. Therefore, Lazarsfeld concluded that the effects of the campaign were not all powerful to the point where they completely persuaded "helpless audiences", a claim that the Magic Bullet, Hypodermic Needle Model, and Lasswell asserted. These new findings also suggested that the public can select which messages affect and don't affect them.
Lazarsfeld's debunking of these models of communication provided the way for new ideas regarding the media's effects on the public. Lazarsfeld introduced the idea of the two step flow model  of communication in 1944. Elihu Katz contributed to the model in 1955 through studies and publications (Katz, Lazarsfeld 1955). The two step flow model assumes that ideas flow from the mass media to opinion leaders and then to the greater public (Katz, Lazarsfeld 1955). They believed the message of the media to be transferred to the masses via this opinion leadership. Opinion leaders are categorized as individuals with the best understanding of media content and the most accessibility to the media as well. These leaders essentially take in the media's information, and explain and spread the media's messages to others (Katz, 1957).
Thus, the two step flow model and other communication theories suggest that the media does not directly have an influence on viewers anymore. Instead, interpersonal connections and even selective exposure play a larger role in influencing the public in the modern age (Severin, Tankard 1979).
See also 
- Berger, A. A. (1995). Essentials of Mass Communication Theory. London: SAGE Publications.
- Croteau, D. & Hoynes, W. (1997). "Industries and Audience". Media/Society. London: Pine Forge Press.
- Davis, D.K. & Baron, S.J. (1981). "A History of Our Understanding of Mass Communication". In: Davis, D.K. & Baron and S.J. (Eds.). Mass Communication and Everyday Life: A Perspective on Theory and Effects (19-52). Belmont: Wadsworth Publishing.
- Katz, E., Lazarsfeld, P.F. (1955). Personal Influence: the Part Played by People in the Flow of Mass Communication's. 309.
- Katz, E. (1957). "The Two-Step Flow of Communication: an Up-To-Date Report on a Hypothesis". The Public Opinion Quarterly, 21 (1). pp. 61-78.
- Severin, W. J. and Tankard, J.W. (1979). Communication Theories -- Origins, Methods and Uses. New York: Hastings House.