Brain's dynamic properties, how it is wired and also how that wiring shifts in response to changing intellectual demands, are the best predictors of intelligence in the human brain, a study of the University of Illinois (UI) found.
"There are the pathways that encode prior knowledge and experience, which we call 'crystallised intelligence.' And there are adaptive reasoning and problem-solving skills that are quite flexible, called 'fluid intelligence,'" said UI Psychology Professor Aron Barbey, who hosted the study, reports Xinhuanet.
Crystallised intelligence involves robust connections, the result of months or years of neural traffic on well-worn pathways. Fluid intelligence involves weaker, more transient pathways and connections that are formed when the brain tackles unique or unusual problems.
"Rather than forming permanent connections, we are constantly updating our prior knowledge, and this involves forming new connections," Barbey said. The more readily the brain forms and reforms its connectivity in response to changing needs, the better it works, he said.
Researchers have long known that flexibility is an important characteristic of human brain function. But only recently has the idea emerged that flexibility provides the basis for human intelligence.
General intelligence requires not only the ability to flexibly reach nearby and easy-to-access states to support crystallised intelligence, but also the ability to adapt and reach difficult-to-access states to support fluid intelligence, Barbey said.
"What my colleagues and I have come to realise is that general intelligence does not originate from a single brain region or network. Emerging neuroscience evidence instead suggests that intelligence reflects the ability to flexibly transition between network states," he said.
The study has been published in the journal Trends in Cognitive Sciences.