As a one-and-done mom of an only child, I’m familiar with the stereotypes. I’ve been warned my son will grow up to be lonely and selfish, and while there may be a kernel of truth to the popular notion that only-children are more likely to be narcissistic, the latest neuroscience suggests they’re actually more likely to be creative thinkers.


A growing body of research on only-children indicates that there are plenty of cognitive benefits from this kind of childhood, and according to a study published in the journal Brain Imaging and Behavior earlier this year, growing up solo leads to measurable differences in brain development that makes only-children think differently than kids with siblings.

Researchers at Southwest University in China tested hundreds of college-age young adults for IQ, creativity and personality traits and looked at the participants’ brains using MRI machines.

What they found was that the brain structures of only-children and those with siblings are visibly different.

The MRI results showed differences in gray matter volume: The brains of only-children had more volume in an area linked to language perception and processing and less volume in an area associated with personality and social behavior.

The cognitive tests backed up what the researchers saw in the MRI machines.

While there was no difference in the IQ scores, the only-children’s test results indicated higher levels of one measure of creative thinking, flexibility, and lower levels of agreeableness than those who grew up with siblings.

Basically, whether or not a kid is raised with siblings does impact their brain development. Neither outcome is necessarily better, but they are different.

According to the study’s authors, there’s still more work to be done before science can say exactly why the brains of solo kids are different, but it’s possible that the higher score on flexibility may be due to parents having more time for, and higher expectations of, only-kids.

Previous studies point to academic benefits of being having one’s parents full attention. According to a meta-analysis of more than 100 studies of only-children, parent-child relationships are an important factor in why only-children surpass most peers (the exceptions being firstborns and people from two-child families) on achievement and intelligence tests.

The research indicates that only-children are like firstborns in that they’re achievement-oriented, but that the stereotypes that paint them as smart yet lonely are unfounded. They’re no less sociable or more neurotic than other kids, just maybe a little more flexible and creative in their thinking.