Your childhood best friend's intelligence probably rubbed off on you

Posted on February 14, 2018

Ryan Charles Meldrum at Florida International University and his colleagues used data collected from intelligence test results from 715 participating kids completed when they were aged 10 and later when they were aged 15. These “target” kids’ individual best friends had also completed an intelligence test when they were aged 11-12.
The IQ of the target kids at age 15 was strongly correlated with the IQ of their best friend when their best friend was aged 11-12. This could be due largely to the fact that children like to be friends with other kids who are similar to them. Critically, however, the target kids’ IQ at age 15, based on a composite of three tests, was still associated (β = 0.08 in a multiple regression) with their best friends’ IQ at age 11-12.
This was even after factoring out their own IQ score when they were aged 10-11, as well as a range of more than nine other confounding variables, such as their mothers’ IQ and education level, and the “enrichment” opportunities in their home. This provides tentative evidence that the target kids hadn’t just chosen childhood friends with an IQ similar to their own, but that their IQ in mid-adolescence had actually been shaped by the intellect of their best friend years earlier.
A few limitations to note were the absence of consideration for fathers’ IQ level and that the intelligence tests, such as the Peabody Picture Vocabulary Test assessed “crystalised intelligence” (depth of knowledge) rather than “fluid intelligence” (mental agility), providing opportunity for future research.


Category(s):Child Development

Source material from Research Digest