Navigation Links
Cortex matures faster in youth with highest IQ

Youth with superior IQ are distinguished by how fast the thinking part of their brains thickens and thins as they grow up, researchers at the National Institutes of Health's (NIH) National Institute of Mental Health (NIMH) have discovered.

Magnetic resonance imaging (MRI) scans showed that their brain's outer mantle, or cortex, thickens more rapidly during childhood, reaching its peak later than in their peers ?perhaps reflecting a longer developmental window for high-level thinking circuitry. It also thins faster during the late teens, likely due to the withering of unused neural connections as the brain streamlines its operations. Drs. Philip Shaw, Judith Rapoport, Jay Giedd and colleagues at NIMH and McGill University report on their findings in the March 30, 2006 issue of Nature.

"Studies of brains have taught us that people with higher IQs do not have larger brains. Thanks to brain imaging technology, we can now see that the difference may be in the way the brain develops," said NIH Director Elias A. Zerhouni, M.D.

While most previous MRI studies of brain development compared data from different children at different ages, the NIMH study sought to control for individual variation in brain structure by following the same 307 children and teens, ages 5-19, as they grew up. Most were scanned two or more times, at two-year intervals. The resulting scans were divided into three equal groups and analyzed based on IQ test scores: superior (121-145), high (109-120), and average (83-108).

The researchers found that the relationship between cortex thickness and IQ varied with age, particularly in the prefrontal cortex, seat of abstract reasoning, planning, and other "executive" functions. The smartest 7-year-olds tended to start out with a relatively thinner cortex that thickened rapidly, peaking by age 11 or 12 before thinning. In their peers with average IQ, an initially thicker cortex peaked by age 8, with gradual thinning thereafte r. Those in the high range showed an intermediate trajectory (see below). While the cortex was thinning in all groups by the teen years, the superior group showed the highest rates of change.

"Brainy children are not cleverer solely by virtue of having more or less gray matter at any one age," explained Rapoport. "Rather, IQ is related to the dynamics of cortex maturation."The observed differences are consistent with findings from functional magnetic resonance imaging, showing that levels of activation in prefrontal areas correlates with IQ, note the researchers. They suggest that the prolonged thickening of prefrontal cortex in children with superior IQs might reflect an "extended critical period for development of high-level cognitive circuits." Although it's not known for certain what underlies the thinning phase, evidence suggests it likely reflects "use-it-or-lose-it" pruning of brain cells, neurons, and their connections as the brain matures and becomes more efficient during the teen years.

"People with very agile minds tend to have a very agile cortex," said Shaw. The NIMH researchers are following-up with a search for gene variants that might be linked to the newly discovered trajectories. However, Shaw notes mounting evidence suggesting that the effects of genes often depends on interactions with environmental events, so the determinants of intelligence will likely prove to be a very complex mix of nature and nurture.

Also participating in the study were Drs. Dede Greenstein, Liv Clasen, Rhoshel Lenroot, and Nitin Gogtay, Child Psychiatry Branch, NIMH; and Drs. Jason Lerch and Alan Evans, Montreal Neurological Institute, McGill University.


'"/>

Source:NIH/National Institute of Mental Health


Related biology news :

1. Quantum dots provide a faster, more sensitive method for detecting respiratory viral infections
2. Muscle repair: Making a good system better, faster; implications for aging, disease
3. Neanderthal teeth grew no faster than comparable modern humans
4. Mosquito study shows new, faster way West Nile can spread
5. Clean skies=faster global warming?
6. Jefferson biologist coaxing human embryonic stem cells to make dopamine with simpler, faster method
7. Picking particles faster than one at a time
8. Researchers develop portable vein finder for faster, more accurate injections
9. Why nerve cells work faster than the theory allows
10. Birds going extinct faster due to human activities
11. New technology enables faster, more efficient cell harvest: Cell therapy meeting study
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/9/2016)... 2016 Paris Police Prefecture ... security solution to ensure the safety of people and operations ... the major tournament Teleste, an international technology group ... announced today that its video security solution will be utilised ... up public safety across the country. The system roll-out is ...
(Date:6/2/2016)... June 2, 2016 The Department of ... awarded the 44 million US Dollar project, for the ... Plates including Personalization, Enrolment, and IT Infrastructure , ... the production and implementation of Identity Management Solutions. Numerous renowned ... Decatur was selected for the most ...
(Date:6/1/2016)... NEW YORK , June 1, 2016 ... Biometric Technology in Election Administration and Criminal Identification to ... According to a recently released TechSci Research report, " ... Sector, By Region, Competition Forecast and Opportunities, 2011 - ... $ 24.8 billion by 2021, on account of growing ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... - FACIT has announced the creation of a ... Propellon Therapeutics Inc. ("Propellon" or "the Company"), to ... of first-in-class WDR5 inhibitors for the treatment of ... an exciting class of therapies, possessing the potential ... patients. Substantial advances have been achieved with the ...
(Date:6/23/2016)... , June, 23, 2016  The Biodesign Challenge (BDC), ... new ways to harness living systems and biotechnology, announced ... (MoMA) in New York City . ... participating students, showcased projects at MoMA,s Celeste Bartos Theater ... Antonelli , MoMA,s senior curator of architecture and design, ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
(Date:6/23/2016)... ... June 23, 2016 , ... Regulatory ... technical consulting, provides a free webinar on Performing Quality Investigations: Getting ... at 12pm CT at no charge. , Incomplete investigations are still a major ...
Breaking Biology Technology: