Is your oldest sibling smarter than you? Could it really be true? All signs point to yes, and your parents are to blame, according to a new study published in the Journal of Human Resources.
The study, based on recent data from the National Longitudinal Survey of Youth Children and Young Adults, found that firstborns perform better on cognitive assessments and also score higher on IQ tests than their siblings, thanks to the undivided attention parents provide before baby No. 2 comes along.
Authors of the study followed nearly 5,000 children from the womb until age 14, evaluating the group every two years though educational assessments.
In addition to the extra brain boost, the study also found that eldest-born children are more likely pursue higher education and earn more money than their younger counterparts.
“The findings showed that advantages enjoyed by first born siblings start very early in life,” the University of Edinburgh’s School of Economics, home to co-author and professor Ana Nuevo-Chiquero, said on their website. The difference in brain power can be seen as early as one-year-old, the study said, and continues well into adulthood.
So second-borns, what gives? The study found that your parents are likely to blame for the intellectual disparities.
Most of the differences in sibling smarts can be attributed to changes in parenting styles from kid to kid. The study found that mothers, “take more risks during pregnancy and are less likely to breastfeed and to provide cognitive stimulation for latter-born children.” Studies show that breastfeeding is linked to increased brain function in babies.
Nuevo-Chiquero said that parents who have more than one child tend to offer less mental stimulation for subsequent spawns.
“Our results suggests that broad shifts in parental behavior are a plausible explanation for the observed birth order differences in education and labor market outcomes,” she told the University of Edinburgh.
Thanks a lot, mom and dad.
