People trying to solve problems in a group lost around 15% of their IQ.
The drop seems to come from the subtle social signals that people send and receive in groups.
Women are particularly vulnerable to an IQ drop from being in a group, the researchers found.
The study had people working in a group after they had received feedback about an earlier IQ test.
Professor Read Montague, who led the research, explained:
"We started with individuals who were matched for their IQ.While IQ was used to send social signals in this study, in the real world it could be how people speak and what they say.
Yet when we placed them in small groups, ranked their performance on cognitive tasks against their peers, and broadcast those rankings to them, we saw dramatic drops in the ability of some study subjects to solve problems.
The social feedback had a significant effect."
Or, it could simply be the social hierarchy in an organisation that is known to everyone, whether consciously or not.
Whatever the method, people get the signal about their social standing and this can affect their IQ.
And feeling lower status lowers your IQ.
Dr Kenneth Kishida, the study's first author, said:
"Our study highlights the unexpected and dramatic consequences even subtle social signals in group settings may have on individual cognitive functioning.Professor Montague concluded:
And, through neuroimaging, we were able to document the very strong neural responses that those social cues can elicit."
"You may joke about how committee meetings make you feel brain dead, but our findings suggest that they may make you act brain dead as well."The study was published in the journal Philosophical Transactions of the Royal Society B (Kishida et al., 2012).
Comment: This study only seems to be comparing what their score was against another person. What they fail to mention is that in the study each person took their own test, as opposed to the group working on one single test. In other words this became a competitive situation where being in a group meant that there was pressure to perform against someone. Had it been a cooperative situation where they all focused their abilities on one problem instead separate ones they might have had a better result. See also: Social sensitivity trumps IQ in group intelligence