IQ Can Actually Fluctuate

Does IQ truly measure your intelligence or is it just another achievement test, much like the SAT, with fluctuations in scores as you gain knowledge?

Maybe more the latter, according to a new study by researchers at University College London. Researchers show that IQs of a group of British teenagers fluctuate - sometimes by a lot:

The researchers tested 33 healthy adolescents between the ages of 12 and 16 years. They repeated the tests four years later and found that some teens improved their scores by as much as 20 points on the standardized IQ scale.

"We were very surprised," researcher Cathy Price, who led the project, tells Shots. She had expected changes of a few points. "But we had individuals that changed from being on the 50th percentile, with an IQ of 100, [all] the way up to being in the (top) 3rd percentile, with an IQ of 127." In other cases, performance slipped by nearly as much, with kids shaving points off their scores.

Price and her colleagues used brain scans to confirm that these big fluctuations in performance were not random — or just a fluke. They evaluated the structure of the teens' brain in the early teen years and again in the late teenage years.

"We were able to see that the degree to which their IQ had changed was proportional to the degree to which different parts of their brain had changed," explains Price. For instance, an increase in verbal IQ score correlated with a structural change in the left motor cortex of the brain that is activated when we speak.

http://www.npr.org/blogs/health/2011/10/20/141511314/iq-isnt-set-in-stone-suggests-study-that-finds-big-jumps-dips-in-teens