How You Nod
psychologists believed that just as smiling can make a person feel happy,
nodding could encourage positive thoughts. It isn't that simple, say
of Ohio State University, Columbus, and Pablo Briñol of the
Autonomous University of Madrid in Spain.
and Briñol asked undergraduates to listen to various radio
editorials through headphones while either nodding or shaking their heads.
As expected, students who nodded during an editorial that made convincing
arguments agreed more strongly with what they had heard than those who
shook their heads. Surprisingly, students who listened to an editorial
that made poorly reasoned arguments had the opposite reaction: Instead of
feeling more positive about what they had heard, those who nodded agreed
less than those who shook their heads. The reason for this
counterintuitive result, Briñol and Petty suggest in the June, 2003 issue of the Journal of
Personality and Social Psychology, is that rather than simply making a
person think more positively, nodding boosts confidence. Just as a speaker
facing a nodding audience would feel more confident about the statements, Petty
and Briñol argue, a person who nods while listening to something
and disagreeing with it would be more certain of that assessment--and
disagree even more strongly. A person who shakes his head might lose
confidence in his or her own judgement, whether it's positive or negative,
like a speaker facing a room full of headshakers.
The study could have
implications for a broad range of situations, including political
campaigns and advertisements, says psychologist Duane Wegener of Purdue
University in West Lafayette, Indiana. Because people tend to
subconsciously mimic what they see, a nodding political candidate or
salesperson could induce nodding in an audience, causing supporters to
agree even more. Nodding could backfire with skeptical listeners by
strengthening their disapproval, says Wegener. "It makes it all the
more important to target your audience."
--by BETSY MASON
Copyright © 2003 by the American Association for the Advancement of Science