See Mass Media

Hypodermic Needle Theory

direct influence via mass media

Or: Magic Bullet Theory

(in Dutch also known as: ‘almacht van de media-theorie’, stimulus-response, injectienaald, transportband, lont in het kruidvat theorie).

History and Orientation

The "hypodermic needle theory" implied mass media had a direct, immediate and powerful effect on its audiences. The mass media in the 1940s and 1950s were perceived as a powerful influence on behavior change.

Several factors contributed to this "strong effects" theory of communication, including:

  • the fast rise and popularization of radio and television
  • the emergence of the persuasion industries, such as advertising and propaganda
  • the Payne Fund studies of the 1930s, which focused on the impact of motion pictures on children, and
  • Hitler's monopolization of the mass media during WWII to unify the German public behind the Nazi party

Core Assumptions and Statements

The theory suggests that the mass media could influence a very large group of people directly and uniformly by ‘shooting’ or ‘injecting’ them with appropriate messages designed to trigger a desired response.

Both images used to express this theory (a bullet and a needle) suggest a powerful and direct flow of information from the sender to the receiver. The bullet theory graphically suggests that the message is a bullet, fired from the "media gun" into the viewer's "head". With similarly emotive imagery the hypodermic needle model suggests that media messages are injected straight into a passive audience which is immediately influenced by the message. They express the view that the media is a dangerous means of communicating an idea because the receiver or audience is powerless to resist the impact of the message. There is no escape from the effect of the message in these models. The population is seen as a sitting duck. People are seen as passive and are seen as having a lot of media material "shot" at them. People end up thinking what they are told because there is no other source of information.

New assessments that the Magic Bullet Theory was not accurate came out of election studies in "The People's Choice," (Lazarsfeld, Berelson and Gaudet, 1944/1968). The project was conducted during the election of Franklin D. Roosevelt in 1940 to determine voting patterns and the relationship between the media and political behavior. The majority of people remained untouched by the propaganda; interpersonal outlets brought more influence than the media. The effects of the campaign were not all-powerful to where they persuaded helpless audiences uniformly and directly, which is the very definition of what the magic bullet theory does. As focus group testing, questionnaires, and other methods of marketing effectiveness testing came into widespread use; and as more interactive forms of media (e.g.: internet, radio call-in shows, etc.) became available, the magic bullet theory was replaced by a variety of other, more instrumental models, like the two step of flow theory and diffusion of innovations theory.

Conceptual Model


Magic bullet theory model
Source: Katz & Lazarsfeld (1955)

Favorite Methods

To be added.

Scope and Application

Mass media.


The classic example of the application of the Magic Bullet Theory was illustrated on October 30, 1938 when Orson Welles and the newly formed Mercury Theater group broadcasted their radio edition of H.G. Wells' "War of the Worlds." On the eve of Halloween, radio programming was interrupted with a "news bulletin" for the first time. What the audience heard was that Martians had begun an invasion of Earth in a place called Grover's Mill, New Jersey.

It became known as the "Panic Broadcast" and changed broadcast history, social psychology, civil defense and set a standard for provocative entertainment. Approximately 12 million people in the United States heard the broadcast and about one million of those actually believed that a serious alien invasion was underway. A wave of mass hysteria disrupted households, interrupted religious services, caused traffic jams and clogged communication systems. People fled their city homes to seek shelter in more rural areas, raided grocery stores and began to ration food. The nation was in a state of chaos, and this broadcast was the cause of it.

Media theorists have classified the "War of the Worlds" broadcast as the archetypal example of the Magic Bullet Theory. This is exactly how the theory worked, by injecting the message directly into the "bloodstream" of the public, attempting to create a uniform thinking. The effects of the broadcast suggested that the media could manipulate a passive and gullible public, leading theorists to believe this was one of the primary ways media authors shaped audience perception.


Key publications

  • Davis, D.K. & Baron, S.J. (1981). A History of Our Understanding of Mass Communication. In: Davis, D.K. & Baron, S.J. (Eds.). Mass Communication and Everyday Life: A Perspective on Theory and Effects (19-52). Belmont: Wadsworth Publishing.
  • Golden, L.L. & Alpert, M.I. (1987). Comparative Analysis of the Relative Effectiveness of One- and Two-sided Communication for Contrasting Products. Journal of Advertising, 16(1), 18-25.
  • Lazarsfeld, P.F., Berelson, B. & Gaudet, H. (1968). The people’s choice: How the voter makes up his mind in a presidential campaign. New York: Columbia University Press.
  • Berger, Arthur Asa Essentials of Mass Communication Theory London: SAGE Publications, 1995.
  • Casmir, Fred L. Building Communication Theories New Jersey: Laurence Erlbaum Associates, 1994.
  • Croteau, David and William Hoynes Media/Society -- Industries, Images and Audiences London: Pine Forge Press, 1997.
  • DeFleur, Melvin L. Theories of Mass Communication New York: Longman Inc., 1989
  • Lowery, Shearon and Melvin L. DeFleur Milestones in Mass Communication Research: Media Effects New York: Longman Inc., 1983.
  • Severin, Werner J. and James W. Tankard, Jr. Communication Theories -- Origins, Methods and Uses New York: Hastings House, 1979.
  • Watson, James and Anne Hill A Dictionary of Communication and Media Studies New York: St. Martin's Press, Inc., 1997
  • Katz, E., & Lazarsfeld, P. (1955), Personal Influence, New York: The Free Press.

See also Two-Step Flow Theory
See also Mass Media