When ranked, ‘stable’ IQ scores drop

CALTECH (US) — Our cognitive abilities suffer when we feel that we are being ranked, such as in the classroom or at work, new research shows.

The finding, from a team of researchers from the California Institute of Technology (Caltech) and four other institutions, flies in the face of long-held ideas about intelligence and cognition that regard IQ as a stable, predictive measure of mental horsepower.

“This study tells us the idea that IQ is something we can reliably measure in isolation without considering how it interacts with social context is essentially flawed,” says Steven Quartz, professor of philosophy at Caltech and one of the authors of the new study, published in the journal Philosophical Transactions of The Royal Society B.

“Furthermore, this suggests that the idea of a division between social and cognitive processing in the brain is really pretty artificial. The two deeply interact with each other.”

“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,” says Read Montague, director of the Human Neuroimaging Laboratory and Computational Psychiatry Unit at the Virginia Tech Carilion Research Institute and corresponding author on the paper.

To investigate the impact of social context on IQ, the researchers divided a pool of 70 subjects into groups of five and gave each individual a computer-based IQ test. After each question, an on-screen ranking showed the subjects how well they were performing relative to others in their group and how well one other person in the group was faring.

All of the subjects had previously taken a paper-and-pencil IQ test, and were matched with the rest of the group so that they would each be expected to perform similarly on an IQ test.

At the outset, all of the subjects did worse than expected on this “ranked group IQ task.” But some of the subjects, dubbed High Performers, were able to improve over the course of the test while others, called Low Performers, continued to perform below their expected level.

By the end of the computer-based test, the scores of the Low Performers dropped an average of 17.4 points compared to their performance on the paper-and-pencil test.

“What we found was that sensitivity to the social feedback of the rankings profoundly altered some people’s ability to express their cognitive capacity,” Quartz says. “So we get this really quite dramatic downward spiraling of one group purely because of their sensitivity to this social feedback.”

Since so much of our learning—from the classroom to the work team—is socially situated, this study suggests that individual differences in social sensitivity may play an important role in shaping human intelligence over time.

During the computer-based test, about a third of the subjects underwent brain scans, using functional Magnetic Resonance Imaging (fMRI). This type of imaging allows scientists to track increases in oxygenated blood flow, indicating heightened activity, in the brain.

At the start of the test, researchers observed increased activity in all the participants in a brain region called the amygdala, which is associated with fear and emotional arousal. Among High Performers, that activation decreased over time, while it remained steady in Low Performers.

“What is causing the Low Performers to be hindered by the social context is something for follow-up studies, but certainly the suspicion is that it’s a dimension of personality that is driving the difference,” Quartz says.

That dimension could be neuroticism, the tendency to worry or to ruminate about social information.

“The pattern of activity that we see originally in both groups, but especially in the low-performing group, is quite similar to the pattern of activity you see in studies looking at the neuroscience of neuroticism,” says Quartz.

The researchers also tracked activity in the nucleus accumbens, a part of the brain involved in the processing of rewards. They observed elevated activity in the nucleus accumbens when a subject’s rank within the group increased. “That shows that the task was motivationally important to people,” Quartz says. “When they saw their rank go up, that was a reward.”

The idea for the new study came, in part, from a study published in 1999 in which researchers from Emory University examined social rank—a strong and extremely motivating signal among primates. It has long been known that even monkeys that have never met before can quickly sort themselves based on social standing within the group.

The Emory researchers isolated low-ranking rhesus monkeys and taught them a learning task. They found that in the presence of high-ranking group members, the monkeys who had learned the task acted as though they were not familiar with it.

“Social rank isn’t as well understood in humans,” Quartz says. “So we wanted to see what would happen when social rank becomes salient in a group of humans, as it does in most real-world learning environments. We wanted to see if this has an effect on the expression of IQ.”

Throughout the 20th century, IQ was used in different arenas as a way of sorting or classifying people into niches. Because people believed it to be a more abstract notion of cognitive ability, it was thought to have strong predictive validity of mental capabilities even from age six. But IQ was always measured in social isolation.

“That reflects a long tradition of intellectual history, of considering rationality and cognition to be this isolated process,” Quartz says. “But one of the things that we’re learning more and more in social neuroscience is the role of our social contexts and the social adaptation of the brain.”

Understanding the role social context plays and its differential impact on the brain may ultimately help educators and others to design more effective learning environments.

The present study found some unexpected trends, including the tendency for female subjects to be more affected than males by the implicit signaling of social status during the test.

Although all of the subjects scored similarly on the paper-and-pencil IQ test, 11 of the 14 Low Performers on the ranked group IQ task were female, while 10 of the 13 High Performers were male. Due to sample size limitations, additional studies are needed to validate the finding and to investigate possible causes.

In addition to Quartz and Montague, additional authors contributed from Virginia Tech Carilion Research Institute, Baylor College of Medicine, and University of California, Los Angeles.

The Wellcome Trust Principal Research Fellowship, the Kane Family Foundation, and the National Institutes of Health funded the work.

More news from Caltech: http://media.caltech.edu

chat6 Comments


  1. Matthew

    Last week I came across this report and was stunned:


    And then I read these statements from a group of intelligence researchers:

    “A person’s intellectual capability remains stable at early adolescence. There is very little individuals can do in their adolescence and adulthood to increase their intelligence. One cannot increase one’s intelligence by studying, by reading books, by receiving education, or by going to better schools. Socioeducational interventions have had minimal if any lasting effects on raising an individual’s intelligence level, though they have affected life outcomes via other routes (keeping more girls from getting pregnant, etc.) There is a strong positive association between intelligence and education across individuals, NOT because further education increases one’s intelligence, but because more intelligent individuals receive more education. Education allows you to quote Shakespeare at will and gives you better understanding of string theory (physics), but it does not alter your intelligence.

    By the time you are 12 or 13 years old, your intelligence is more or less set for the rest of your life, and it’s largely up to your genes. Of course there are a lot of factors that can lower one’s intelligence below what your genes alone would have produced (malnutrition, ill health, head trauma, total sensory isolation, etc.), but there are virtually no factors that will raise your intelligence above what your genes alone would have produced…”


    Three questions:

    1. Do the findings from the college report surprise you and do you agree with the blogger’s comments?

    2. Do you think the above statements on intelligence are broadly consistent with the evidence?

    My brief take on this is that no one bats an eye lid when it is suggested that other physical traits or susceptibility to diseases are genetic, but as soon as you say intelligence is inherited every one thows their hands up in alarm. Yet the brain is just another organ and while learning experiences hone its usefullness what else shapes its capacity (fitness for survival) to develop if it isn’t genetic?

    Rex Brinkworth who founded the Down’s Syndrome Association was convinced that intelligence can be acquired and even enhanced by learning while Prof. Cliff Cunningham who also studied child development claimed his studies showed that intelligence was inherited and could not be ‘improved’.

    I personally don’t get upset that I don’t have the mental capacity of Isaac Newton but then I didn’t have his genes either. More to the point if his parents had engaged in sexual congress on a different night of the week he wouldn’t have existed at all and their offspring may have been a dullard who passed unnoticed

  2. Aces

    Fascinating study. I can imagine this also carries over to personal relationships.

  3. Donald K. McKenzie

    Fascinating. I have long observed that some people thrive on competition, while others are crushed by it. Some people are team players and others are not. I suspect that these observations are much related to this studies indications.

  4. emc2

    to matthew, height and other fixed attributes have few dimensions. e.g., up and down. Intelligence has countless dimensions, and many can be altered at will. Tibetan monks can raise or lower their blood pressure on command. Intelligence is a construct that is hard to define. The minute we define it, it doesn’t seem intelligent anymore. I think this study is a very useful reminder of the danger in labeling some people as smart, and others as dull. I find that people who are very smart in one area, can be unusually dumb in others. I’ll bet Isaac Newton was clueless about many things.

  5. this_guy

    And so I wonder if this could be some type of psychosis wherein the mind assumes the identity of the brain_dead. To realize the potential of controlling one’s own responses to the thoughts of the mind is to harness some great energy within us. It is by our thoughts that we are guided; everyone has the potential for brilliance. Hmm…what if it’s a fear response?

  6. Linda Pretty

    It seems to me that nature vs nurture, again is unclear. The child raised to value their own interests and have answered their own speculations about life just might have the self-confidence to speculate those unpopular or unsanctioned theories and to persevere in their study despite resistance by those accepting the norm, and to actually move the species closer to understanding truths. I for one, don’t want to be fooled by the soothsayers.

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