magazine issue 4 2009 / Issue 9

Embodied Persuasion: How the Body Can Change our Mind

• written by Pablo Briñol
• edited by Selin Kesebir

The link between our mind and our bodily responses has long been studied by persuasion researchers. It goes back to the use of the term "attitude" to refer to the posture of one’s body (Galton, 1884), and to the notion that attitudes may reflect—and be influenced by—expressive motor behaviors (e.g., a scowling face can indicate a hostile attitude; Darwin, 1872). Colloquially, it is common to refer to an attitude as an individual’s position on an issue, although the meaning in this case refers to an evaluative, rather than a physical, orientation.

The main idea behind the concept of embodied persuasion is that people’s own behaviors can impact their attitudes (their likes and dislikes). Indeed, when we smile, we tend to be happier than when we frown, and see everything with a positive light. Also, when we nod our heads we tend to like things better than when we shake our heads. For example, in a classic study, individuals who were induced to nod their heads (i.e., agreement behavior) while listening to a persuasive message were more favorable to the proposal than people who were induced to shake their heads (i.e., disagreement behavior) while listening to the same message (Wells & Petty, 1980). Other research has found that information presented while performing an approach behavior (e.g., using one’s hands to pull up from underneath a table) is evaluated more positively than information presented during an avoidance behavior (e.g., pushing down on a table top surface; Cacioppo, Priester, & Berntson, 1993). Similar findings have been found for a large number of behaviors, postures, and body movements (for a review, Briñol & Petty, 2008).

Although the ability of bodily movements to influence attitudes seems to be a well-established phenomenon, most research on this topic has not focused on the psychological mechanisms by which the body affects attitudes. Understanding these processes is essential in order to predict whether, when, and how attitudes will change, as well as to predict whether, when, and how attitudes will result in further behavioral changes. That is, although we might like something more when we smile (vs. frown) or when we nod our heads (vs. shake), it is important to understand the processes responsible for these changes in evaluation. It might be that agreement behaviors such as smiling and nodding make us think about everything in a positive light, or it might be that they encourage us not to think much about the information we receive.

Because these (and other) mental operations are very different, Richard Petty and I have organized the literature on embodied persuasion around the basic mechanisms by which the body can influence our attitudes. The psychological processes relevant to attitude change can be organized into a finite set. A person’s bodily movements or responses, like other variables in persuasion settings, can influence attitudes by affecting one or more of these underlying processes: (a) serving as simple peripheral cues to change, (b) affecting the amount of issue-relevant thinking that occurs, (c) producing a bias to the thoughts that come to mind, and (d) affecting structural properties of the thoughts (e.g., thought confidence). Among other things, identifying the processes by which bodily movements affect attitudes is informative about the immediate and long-term consequences of persuasion.

Bodily Responses Serve as Simple Cues to Persuasion

Our body posture, our facial expressions, and the way we movecan all influence our opinions in very subtle ways. In fact, because bodily responses belong to our physical nature, researchers tend to think that they have to operate in our mind through very simple, automatic mechanisms. However, the body can influence our attitudes by processes that require both low and high degrees of cognitive effort. Under low-effort conditions, our actions can influence our opinions on a topic even when we do not think about the information we receive. The body is likely to serve as a simple cue when motivation and ability to think are constrained. For example, Cacioppo, et al. (1993) observed that neutral Chinese ideographs (irrelevant stimuli for the sample of participants) presented during arm flexion were subsequently evaluated more favorably than ideographs presented during arm extension. In another line of research, Strack, Martin, and Stepper (1988) asked participants to either hold a pen between their teeth (which facilitates a facial expression similar to smiling) or to hold a pen between their lips (which inhibits smiling) while watching cartoons. Although participants did not recognize the meaning of their facial expressions, they judged the cartoons to be funnier in the former condition than in the latter.