[3] 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.
Though the "magic bullet" and "hypodermic needle" models are often credited to Harold Lasswell's 1927 book, Propaganda Technique in the World War,[5] neither term appear in his writing.
"[6] Recent work in the history of communication studies have documented how the two models may have served as strawman theory or fallacy[7] or even a "myth".
[9] The phrasing "hypodermic needle" is meant to give a mental image of the direct, strategic, and planned infusion of a message into an individual.
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.
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.
Social media has become an increasingly individualized experience and process, thus users are likely to form opinions based on the content they are exposed to and interact with.
[16] More recently, the use of big data analytics to identify user preferences and to send tailor-made messages to individuals led back to the idea of a "one-step flow of communication", which is in principle similar to the hypodermic needle model.
This social relationship has led to behavior changes in the digital age, some of which align with characteristics of the hypodermic needle theory.
Similarly, contemporary research considers libraries and information centers as a form of media because of their influence over knowledge and source selection.