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Fade the Butcher
04-02-2006, 04:52 AM
Found this over at Dienekes blog.

Nature (http://www.nature.com/nature/journal/v440/n7084/full/nature04513.html)

http://photos1.blogger.com/blogger/5379/496/400/nature04513-f2.2.jpg

Nature 440, 676-679 (30 March 2006)

Intellectual ability and cortical development in children and adolescents

P. Shaw et al.

Children who are adept at any one of the three academic 'R's (reading, writing and arithmetic) tend to be good at the others, and grow into adults who are similarly skilled at diverse intellectually demanding activities1, 2, 3. Determining the neuroanatomical correlates of this relatively stable individual trait of general intelligence has proved difficult, particularly in the rapidly developing brains of children and adolescents. Here we demonstrate that the trajectory of change in the thickness of the cerebral cortex, rather than cortical thickness itself, is most closely related to level of intelligence. Using a longitudinal design, we find a marked developmental shift from a predominantly negative correlation between intelligence and cortical thickness in early childhood to a positive correlation in late childhood and beyond. Additionally, level of intelligence is associated with the trajectory of cortical development, primarily in frontal regions implicated in the maturation of intelligent activity4, 5. More intelligent children demonstrate a particularly plastic cortex, with an initial accelerated and prolonged phase of cortical increase, which yields to equally vigorous cortical thinning by early adolescence. This study indicates that the neuroanatomical expression of intelligence in children is dynamic.

Fade the Butcher
04-02-2006, 05:17 AM
http://static.flickr.com/47/119915106_fa77b8bb09_o.jpg

http://scienceblogs.com/grrlscientist/2006/03/delayed_brain_development_asso.php?utm_source=combined-feed&utm_medium=rss

A new study will be published tomorrow revealing that, on average, human brains mature later in those people who have the greatest intelligence. This research was done using magnetic resonance imaging (MRI) to visualize the regions of children's brains as they matured (example of an MRI pictured, right. Source linked from image). The scientists' data show that the outer portion of the brain, the cortex -- or the thinking part of the brain -- thickens and then thins during early childhood years, when the children were approximately 6 years old. However, they found that kids with greater intelligence show these same changes later than those with average intelligence -- some as late as 11 years of age.

How might this slowed pattern of brain development contribute to increased intelligence? This delay may promote higher intelligence because it means a child is older and is therefore processing more complex experiences while the cortex is still maturing, said study co-author Judith Rapoport. By mapping out the precise details of normal brain development in humans, this research could help scientists and doctors to understand how brain disorders develop. Results appear in tomorrow's issue of the top-tier journal, Nature.