In today's health matters, a teen's intelligence, as measured by an IQ test, may fluctuate throughout adolescence.

Researchers gave 33 individuals between the ages of 12 and 16 IQ tests and brain scans in 2004.

Four years later, these people were tested again.They found some people's IQ scores improved by as much as 20 points while others saw declines.

Study authors say the fluctuations seemed linked to certain areas of the brain. They note they did not determine what was behind the variations.

And hope further research in a larger study confirms their results. Findings appear in the Journal 'Nature.'