Angier, Natalie. "Study Finds Region of Brain May Be Key Problem Solver," New York Times,

 

Angier, Natalie. "Study Finds Region of Brain May Be Key Problem Solver," New York Times,
21 July 2000, p. A13.

Addressing a longstanding debate among scientists over how much of the brain is activated to
perform a difficult task like taking an I.Q. test, researchers have found that a surprisingly small
and specific region of gray matter may be the brain's master problem solver.

The results suggest that the venerable "seat of human intelligence" is less of a throne in
dimensions than a footstool.

Dr. John Duncan of the Cognition and Brain Science Unit of the Medical Research Council in
Cambridge, England, and his colleagues report in today's issue of the journal Science their brain
imaging studies of people who were asked to solve I.Q.-type questions, including spatial
problems that required looking at four geometric images on a display monitor and trying to figure
out which did not fit with the others; and verbal tasks that involved finding a pattern to complex
sequences of letters.

The scientists wondered whether large areas of the brain would light up on their scans as the
subjects sweated and figuratively gnawed on their No. 2 pencils, or whether a limited locus of the
brain would be the intellect's central headquarters.

As it turned out, the same confined region was activated whether the subjects were tackling
verbal or spatial problems. The region in question, called the lateral prefrontal cortex, comes in
pairs, one for each hemisphere of the brain. It is somewhat above the outer edge of the eyebrow,
and corresponds roughly to where someone would rest his head in the palm of the hand when
cogitating or daydreaming. This is the same region of the brain that previous neuroimaging
studies had shown to be important for solving novel tasks, keeping many things in mind at once,
and screening out irrelevant information.

"What we're seeing here seems to be a global workspace for organizing and coordinating
information and carrying it back to other parts of the brain as needed," Dr. Duncan said in a
telephone interview.

It is the relative performance of this cerebral workspace, he said, that intelligence tests appear to
measure, and that determines how deft a person is at solving a broad range of cognitive
problems.

"Some people are blessed with a workspace that functions very, very well," he said.

Indeed, he and his colleagues see this region of the brain as so crucial to high-level thinking that
they boldly titled their report "A Neural Basis for General Intelligence." However, their
neuroimaging studies to not answer incendiary questions like whether current standardized tests
"really" measure intelligence, or are culturally or otherwise biased. Nor does the research say
anything about whether the performance of the lateral prefrontal cortex is largely innate, or is
heavily influenced by learning and experience.