Any teacher who has tried to get an 8th-grader to admit an interest in algebra when his friends find it boring knows how difficult it can be to get students to swim against the tide of social influence. A study set to be published in the April issue of Psychological Science may point to why peer pressure is so hard to fight: It changes the brain itself.
"I think for a long time conforming has been viewed as a bad thing...predicated on the idea that conformity is a form of lying; it's that you know what your private preferences are and the only reason you would conform is to suck up to a group or a person," said Jamil Zaki, a psychology postdoctoral fellow at Harvard University in Cambridge, Mass., "but maybe it's not really like that at all; maybe it's something a lot more profound, that it changes the way you think."
A Harvard research team—Mr. Zaki, Jason Mitchell, a psychology professor, and Jessica Schirmer, a research assistant—asked 14 men, ages 18 to 26 to rate the attractiveness of digital images of female faces. The participants were told that several hundred young men their age had already taken the test, and they would from time to time see the average attractiveness rating by their peers after they had rated a picture.
The "peer rating" was a sham; after the participants had rated enough pictures to give a baseline, a computer automatically generated fake ratings for some of the images either equal to the participant's stated rating or a few points above or below. After the men had reviewed 180 photos, they were given a half-hour break and asked to re-rate the pictures while their brains were scanned via magnetic-resonance imaging.
The team found participants uniformly changed their rating of the faces to match that of their "peers," though when asked, the young men insisted they had not changed any of their ratings between the first and second cycles. More importantly, the MRI scans of the participants' brains showed significantly different patterns of activity in two areas of the brain associated with determining subjective value and reward. When a participant saw a face his "peers" had rated more highly than he had, his brain responded significantly more than when he saw a face that had been rated lower, regardless of what his own initial rating had been.
What does this have to do with education? Think back to that teacher trying to interest her students in algebra. This suggests that being in a class with other people who are interested in the subject can make a student more engaged, too, Mr. Zaki said.
"One of the broad ideas our research is suggesting is that what you like and are motivated by can be really altered by what people around you like and find motivating to them," Mr. Zaki told me. "It's not just that you will want to learn because you want to compete with them or want to fit in, but you will actually perceive the academic work privately as more rewarding."
It may also provide more support for research that shows changes to overall school culture can have a greater impact on student achievement than isolated programs. "It's one thing to change one kid's motivation, but I think the goal is to create cultural norms in a classroom or group," he said. "You don't want just one standout student and the rest of the students hating school."
The study builds on a 2009 study by Gregory S. Berns, a neuroeconomics professor at Emory University in Atlanta, which found adolescents rated their pleasure in songs more highly after learning their popularity.
Mr. Zaki said the team plans additional studies to determine whether people of different ages respond to peer pressure differently; how long the brain changes caused by conformity last; and how peer-driven motivation can affect behavior.
The full article, "Social influence modulates the neural computation of value," is expected in the April edition of Psychological Science. An early version is available here.