IQ Scores of Teens May Change Over Time
Study Shows IQ Scores Can Fluctuate Over the Course of Several Years
Brain Changes continued...
Decreases or increases in the density of gray matter in a region associated with speech corresponded with better or worse verbal test scores. Similar changes were noted in the area of the brain tied to hand movement among students whose performance IQ scores had shifted.
Those scans, Price says, confirm the researchers' findings that the changes in test scores are likely real.
"When we saw the fluctuations in [IQ test] performance, we were concerned that this was measurement error (e.g. differences in concentration on the different testing times)," Price says. "However, then we found that the degree to which verbal or nonverbal IQ changed was mirrored by changes in brain structure."
Capacity for Change
One important finding, Price points out, is that teens, whether they test high or low, appear to have an equal capacity to change -- for better or for worse.
"It was NOT the case that the young low performers got better and the young high performers averaged out," Price says. "If a teenager has poor nonverbal skills, this doesn't mean that they don't have the potential to improve these skills. Likewise, if a teenager has good nonverbal skills, this does not mean that they will maintain these skills without practice."
Price is unable to say with certainty what accounts for such changes. Some teens may simply be early or late bloomers. Brain development can also be influenced by what students focus on in their studies. If they neglect verbal-oriented learning, for instance, their scores may reflect that.
"What we don't know is what occurred first, the change in the [brain] structure or the change in skills," Madison Berl, PhD, tells WebMD in an email.
Berl, a pediatric neuropsychologist at Children's National Medical Center in Washington, DC, who was not involved in the study, says that the research is encouraging in two ways.
"I would say that like the authors point out, IQ is not as rock-solid stable by an early age as most people believe, which is good news in terms of there being an opportunity to continue to learn and gain skills," Berl says. "[And] it is another step in the possibility that sophisticated neuro-imaging tools may be used to monitor [mental] development."