A team of researchers from University College London and Aarhus University in Denmark may have uncovered some clues to help explain why we care what other people think — and why some people care more than others. The research, published in the journal Current Biology, suggests that the area of our brains associated with reward is more active when others agree with, and reinforce, our own opinions. What’s more, they posit that, by examining individuals’ level of activity in this reward center, they could even predict which people are likely to be the most influenced by others’ opinions.
For the study, researchers recruited 28 volunteers and asked them to make a list of 20 songs that they liked, but didn’t own a copy of. They were then asked to rate each song on a scale from 1 to 10 based on how much they appreciated — and wanted to own — that music, with 10 being the highest level of desire. Then, while participants’ brain activity was being monitored using functional Magnetic Resonance Imaging (fMRI) scans, researchers played one song from the participants’ list, followed by another unknown song. After hearing the songs, participants were asked to explain which they preferred.
After they had expressed their own opinions on the music, the researchers let participants known what two “experts” thought about the two selections. They found that, when participants opinions coincided with those of the unknown “experts,” the area of the brain associated with reward — the ventral striatum — lit up with activity. And the more validation they got, the more activity researchers noted. (That is, when both “experts” agreed with their views, activity in the brain’s reward center was even more pronounced than when just one agreed.)
The study authors confirmed this effect with a more direct reward assessment as well. In another activity, participants’ song choices were measured by whether or not each song received a token (which were randomly assigned to the song selections). When their choices earned tokens, the ventral striatum again lit up.
After the exercises, participants were again asked to rate their song choices on a scale of 1 to 10. Researchers found that, while a handful of participants changed their ratings to oppose the opinions expressed by the two experts (giving higher marks to songs that the “experts” had panned), most participants opted to change their ratings to reflect the expert opinions. The study authors found that, the people who were more likely to be swayed by experts’ opinions were the same people who had exhibited the greatest amount of activity in the brain’s reward center.
In a statement about the research, Chris Frith, emeritus professor of neuroscience at UCL’s Wellcome Trust Center for Neuroimaging, summed up the significance of the findings this way:
“It seems that not only are some people more influenced by the opinions of others, but by looking at activity in the brain, we can tell who those people are.”
The authors conclude that the reward sensation of meeting with others’ approval may help explain the rapid spread of trends and values through society.