HELSINKI — Did you know that numerous studies have found a link between height and intelligence? While people on the shorter end of the height spectrum are almost certain to disagree, tall people tend to be smarter, at least according to the research. So, how could this be the case? A joint study conducted by researchers at the University of Helsinki in Finland, University of California San Diego, and Boston University have found another factor in this relationship: brain size.
Researchers analyzed the relationship between height and intelligence using brain size, or more specifically the size of cortical gray matter, as a mediator. They found that the taller a person is, the more likely they are to have a larger cerebral cortex, which is associated with better cognitive ability or intelligence.
“Even though taller individuals have, on average, bigger brain[s] compared to shorter people, the size of any given individual’s brain cannot be determined by their stature alone. Further, cognitive ability is not simply determined by brain size,” says corresponding research article author Eero Vuoksimaa in a release. “The findings do, however, shed light on the biological mechanism underlying the association between height and cognition.”
The researchers measured the cortical surface area of American men aged 50 to 60 years old, focusing on total cortical surface area and average cortical thickness. The findings showed that the total surface area was larger in tall people, but height was not related to cortical thickness.
The team measured cognitive ability with a paper-and-pencil test utilizing questions measuring verbal, mathematical, spatial, and reasoning abilities.
The study’s authors say that while genetic differences account for most people’s differences in height, cognitive ability, and brain size, environmental or societal factors can also play a role. “For example, childhood malnutrition has an impact on both height and brain growth, and affects also cognitive development,” comments Vuoksimaa.
The study is published in the journal Brain Structure & Function.