Does nature or nurture influence how smart a child will be? Although genetics does influence intelligence, new research also suggests that children who are nurtured in the most ideal environments tend to have greater intelligence.
The study, published in the journal Proceedings of the National Academy of Sciences, compared the cognitive ability of 436 male sibling pairs in Sweden, one of which was brought up by biological parents and the other by adoptive parents. The IQ of each sibling was measured between the ages of 18 and 20, and each parent's education level was also rated on a five-point scale (though the study did not distinguish intelligence between the parents).
Researchers found that the IQ of siblings raised by their biological, and typically less-educated, parents were 4.4 points lower than siblings who had been adopted into higher-educated and more financially-secure families.
"The adoptive parents tended to be more educated and in better socioeconomic circumstances than the biological parents," reports PsychCentral. But when biological parents were more educated, the raised sibling actually had a higher IQ.
However, there is evidence from past studies that may dispute these recent findings. In particular, a 2014 study analyzed parental behaviors and verbal intelligence found that IQ may not actually be the result of parental socialization. Despite this, Kenneth S. Kendler, M.D., one of the study's joint first authors said, "We're not denying that cognitive ability has important genetic components, but it is a naí¯ve idea to say that it is only genes."
Determined to boost your child's intelligence as much as possible? There is recent evidence that breastfeeding your child for at least 12 months could increase their IQ by as much as four points. And another new study affirms that making sure your child has enough schooling -- and academic challenges -- can also help develop smart kids.
Caitlin St John is an Editorial Assistant for Parents.com who splits her time between New York City and her hometown on Long Island. She's a self-proclaimed foodie who loves dancing and anything to do with her baby nephew. Follow her on Twitter: @CAITYstjohn
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