Advertisement

Bigger brains don't score higher on IQ tests

Analysts point to the superior significance of brain structure -- not size -- in predicting intelligence.

By Brooks Hays
Bigger brains don't score higher on IQ tests
Brain size has only a weak relation to IQ, researchers say. Photo by Suzanne Tucker/Shutterstock

GOTTINGEN, Germany, Oct. 14 (UPI) -- Bigger may be better, but not necessarily when it comes to brain size and intelligence.

For decades, centuries even, scientists have looked at the relationship between brain size and smarts. The results have been inconclusive, at best.

Advertisement

Recently, researchers looked to offer some clarity (and maybe some finality) on the subject with a meta-analysis of some 148 studies comprising data on the brain sizes and IQ scores of more than 8,000 participants.

The analysis showed only a weak relationship between the size of a person's brain and their IQ score. Though many studies found larger brains were linked with higher IQ scores, the predictive value of brain size was deemed to be minimal.

RELATED Brains vs. AI: Computer faces poker pros in no-limit Texas Hold'em

The new meta-analysis -- carried out by researchers from Austria, Germany and Netherlands and published in the journal Neuroscience and Biobehavioral Reviews -- suggests the role of brain size in determining IQ has been exaggerated and oversold in the scientific literature.

"While it is tempting to interpret this association in the context of human cognitive evolution and species differences in brain size and cognitive ability, we show that it is not warranted to interpret brain size as an isomorphic proxy of human intelligence differences," researchers concluded in their paper on the subject.

Advertisement

The researchers used the differences between men and women as evidence of their general conclusion. Men have consistently larger brains than women, but there is no difference between the sexes when it comes to global IQ test performance.

RELATED Researchers simulate part of a rat brain

Instead, the analysts point to the superior significance of brain structure.

"Brain structure and integrity appear to be more important as a biological foundation of IQ, whilst brain size works as one of many compensatory mechanisms of cognitive functions," Jakob Pietschnig, a researcher at University of Vienna's Institute of Applied Psychology, said in a press release.

RELATED Testosterone therapy reveals differences between male, female brains

RELATED Words change how the brain sees things

RELATED Study: Poverty does lasting damage to a child's brain

Latest Headlines

Advertisement
Advertisement

Follow Us

Advertisement