A primary mystery puzzling neuroscientists - where in the brain lies intelligence? - just may have a unified answer.
In a review of 37 imaging studies related to intelligence, including their own, Richard Haier of the University of California, Irvine and Rex Jung of the University of New Mexico have uncovered evidence of a distinct neurobiology of human intelligence. Their Parieto-Frontal Integration Theory (P-FIT) identifies a brain network related to intelligence, one that primarily involves areas in the frontal and the parietal lobes.
Their report includes peer commentary from 19 researchers and appears online in the journal Behavioral and Brain Sciences.
“Recent neuroscience studies suggest that intelligence is related to how well information travels throughout the brain,” said Haier, a professor of psychology in the School of Medicine and longtime human intelligence researcher. “Our review of imaging studies identifies the stations along the routes intelligent information processing takes. Once we know where the stations are, we can study how they relate to intelligence.”
The data suggest that some of the brain areas related to intelligence are the same areas related to attention and memory and to more complex functions like language. Haier and Jung say this possible integration of cognitive functions suggests that intelligence levels might be based on how efficient the frontal-parietal networks process information.
Brain imaging studies of intelligence are relatively new, with Haier doing some of the first ones only 20 years ago. Although there is still discussion about how to define and measure intelligence, Haier and Jung found surprising consistency in the studies they reviewed despite the fact the studies represented a variety of approaches.