What role does motivation play in IQ testing?

IQ test

New psychology research at Penn demonstrates a correlation between a test-taker’s motivation and that person’s performance on an IQ test and, more important, between that performance and a person’s future success.  

Angela Lee Duckworth, an assistant professor of psychology, led the research, which involved two related studies.

The first was an analysis of previous research into the effect of incentives on IQ scores. For individuals who had above-average scores at baseline, motivation accounted for only about four points. But, for those who had below-average scores, motivation made up almost fifteen points.

The second study involved an experiment in which researchers observed video footage of adolescent boys taking a standard IQ test to rate their motivation, and then measured how well the boys fared more than a decade later in terms of criminal records, job status and educational attainment.

As part of the study, coders, who were not aware of subjects’ IQ scores or the hypothesis of the study, rated each subject’s motivation based on a standard set of behaviors, such as refusing to answer questions or obviously rushing through the test to make it end as quickly as possible.

“IQ scores are absolutely predictive of long-term outcomes,” Duckworth says. “But what our study questions is whether that’s entirely because smarter people do better in life than other people or whether part of the predictive power comes from test motivation.

“Could it be that part of the reason doing well on this test predicts future success is because the kinds of traits that would result in you doing well —compliance with authority, self-control, attentiveness, competitiveness — are traits that also help you in life?” she says. “This means that for people who get high IQ scores, they probably try hard and are intelligent. But for people who get low scores, it can be an absence of either or both of those traits.”

Originally published on April 28, 2011