Inoculation Theory
Overview
A brief outline of inoculation theory. Intended audience: undergraduate psychology students.
Think back to the last time you got a flu shot. You likely knew that flu season was coming and didn’t want to get sick, so you decided to allow someone to inject you with a small, deactivated segment of the flu virus so that your body could promote antibodies to keep you healthy should you encounter the real thing in the wild. Because of your foresight in receiving the vaccine, you were able to remain healthy throughout the flu season. Inoculation Theory posits that just as our bodies grow stronger with exposure to an inactive virus, our attitudes can become more resistant to change with exposure to weak arguments that are easily refutable.
Inoculation theory was developed in 1961 by the social-cognitive psychologist William McGuire (McGuire, 1961a; McGuire, 1961b) at the University of Illinois. In a seminal inoculation theory study (McGuire & Papageorgis, 1961), participants were exposed to experimental manipulation, including either an inoculation or a control condition, during an initial laboratory session prior to returning to the lab two days later for a second data collection session. In the experimental manipulation period, participants were assigned to read or write about a cultural truism they supported (e.g., value in daily tooth brushing, efficacy of penicillin). Participants read either a prompt/essay in favor of their supported belief or a prompt/essay in favor of their belief, in addition to multiple weak arguments attacking their belief and counterarguments against these attacks. The type of message received by participants in the inoculation condition, containing both weak arguments against the held attitude and rebuttals to these arguments, is known as a refutational pretreatment (McGuire, 1964) or two-sided message (Allen, 1994). Messages received by participants in the control condition, without weak attitude attacks, are known as supportive pretreatments or one-sided messages (McGuire, 1964).
Two days after the manipulation session, participants returned to the lab for a data collection session. During the data collection, participants read two strong counterarguments to the truism they initially endorsed, plus an additional counterargument to an unrelated belief. Following exposure to the strong counterarguments, participants exposed to two-sided messages (those in the inoculation condition) displayed greater levels of belief in the statement they originally endorsed than those exposed to one-sided messages in support of their stance.
In the years following early studies such as the experiment described above, the literature surrounding McGuire’s inoculation theory experienced substantial growth. Indeed, meta-analytic approaches have supported the hypothesis that exposure to inoculating messages is associated with greater resistance to attitude change with a small to moderate effect size (Banas & Rains, 2010). Inoculation theory has been applied to protect positive attitudes related to health behaviors, such as the protective utility of vaccinations (Wong & Harrison, 2014) and engagement in safe-sex practices (Parker et al., 2012). Examples such as these illustrate the role that attitude inoculation can play in our society, but how can inoculation theory explain this phenomenon from a social-cognitive perspective?
The main components of the inoculation model are threat, counterarguing, and refuting (Compton, 2013; McGuire, 1964). If a persuasive message threatens a receiver's perceptions of the security of a held attitude, it is considered threatening (Compton, 2013). Threatening messages can further be subcategorized into messages that contain both implicit and explicit threats. Messages that present alternative viewpoints or challenges to an existing attitude are classified as implicit, whereas messages that directly signal direct persuasion are explicit threats (Compton, 2013; McGuire, 1964). Exposure to threats catalyzes the individual to search for further justification to support their extant attitude or position, prompting engagement in counterarguing and refutation.
Counterarguing and refuting is the process of compiling responses and rebuttals to the content of a message that presents a threat to one's position or attitude. Although McGuire’s early work investigating inoculation and many studies following incorporated refutational pretreatments to support engagement in counterarguing processes, individuals can engage in counterarguing organically without immediate prompting (Compton, 2013). For example, suppose you are debating a political topic with a friend, and they make a statement that either implicitly or explicitly threatens your extant political attitude. In this situation, you will likely engage in counterarguing processes to maintain a consistent stance - searching for gaps in their logic or engaging in additional research to support your own political attitude.
Research examining inoculation theory has identified various persuasive phenomena that can be understood through the framework of inoculation. One such occurrence is spreading inoculation, which occurs when the content of inoculation messages spreads throughout a social network (Compton & Pfau, 2009). As noted by Compton & Pfau (2009), attitude inoculation increases both the accessibility of an attitude (Pfau et al., 2003) and the willingness to discuss the inoculated attitude (Lin & Pfau, 2007). With these factors in mind, inoculation of an attitude may lead to the inoculated individual sharing their attitude more frequently with others, potentially prompting attitude threat for others in their network. With the advent of social media, some researchers suggest the potential for spreading inoculation to occur through virtual mediums such as social networks (Compton et al., 2021).
The generalizability of inoculation within inoculation theory is another area that has received much attention within the attitude inoculation literature. Throughout a vast number of studies investigating the generalizability of attitude inoculation effects, meta-analytic approaches have found no significant differences in an attitude's resistance to persuasion between novel threats to an inoculated attitude and the originally refuted threat (Banas & Rains, 2010). In other words, if you were to successfully refute an attack on an attitude you hold, that same attitude would be more resistant to change from entirely different attacks. For example, if you hold the attitude “Devoting resources to protect the environment is a worthwhile endeavor,” and you successfully refute the attack “Protecting the environment is not worth the economic burden it carries with it,” then your attitude will also be more resistant to novel attacks such as “There is only so much we can do to protect the environment, so why bother?”.
Because of the generalizability of inoculation across topographically different attitudinal attacks, some scholars have investigated alternative persuasive strategies to circumvent the extensive inoculation many individuals build throughout normal social interactions. One such approach is directly targeting values that underlie cognitive architecture supporting attitudes themselves. Indeed, indirectly attacking attitudes through related values is more effective than attacking attitudes themselves, potentially due to the fact that underlying values are threatened less frequently than attitudes (Bernard et al., 2003; Blankenship et al., 2015).
As we go throughout our everyday lives, our own attitudes and beliefs are constantly being put to the test. Through repeated exposure to threats and repeated generation of refutations, our attitudes grow stronger and less susceptible to change. Take a moment to consider an attitude you hold, thinking back to a moment when it was challenged. Were you able to successfully refute the threat? Do you feel that your attitude was stronger because of it?
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References
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