Friday, November 04, 2011

Fluctuating IQ in Teens

A new study in Nature this past month indicated that the teenage brain is fairly plastic; that IQ can change a reasonable amount during those years of rapid physical change (You can read one write-up of the study here).

As usually happens, some of the commentary on this study has raised the question of whether giftedness exists, or if it just captures a moment in time. But I think this misses the point -- while IQ may not be absolutely constant, a child whose IQ measures at, say, 150, is unlikely to then measure at 100. And just because IQ can change doesn't mean that giftedness shouldn't be accommodated. Gifted education is an intervention for children who need it. If one doesn't view it as a reward, then there's no reason children couldn't move in and out of needing services over time. It's something to consider.


Anonymous said...

To what extent are they merely exhibiting the limitations of IQ testing, rather than talking about true changes? After all, there is no such thing as actually measuring "ability"; you're always looking at achievement of some kind. It's just that "ability" tests try to get at types of achievement that are less correlated with direct training/education.

I don't really understand why people expect perfect consistency in these matters anyway. It's perfectly reasonable to look at actual medical tests that measure something fairly concrete, such as cholesterol or blood pressure levels, and see a wide variation, even when the patient has, on the whole, consistently high or consistently low levels. You'd never say, well, this time she was 90 over 50 and another time 106 over 65, and therefore low blood pressure doesn't exist. All the more true when you're looking at tests that are measuring something only tangentially related to a complicated, inchoate concept.

Paul said...

I suspect from anecdotal experience that "IQ" fluctuates significantly in all of us from day to day or even hour to hour depending on a number of factors like how good our sleep was the night before and our physical health. It's probably not unlike blood pressure.

That's why I fear we put too much stock in isolated IQ tests. Maybe they just got my son on a particularly good day? Because some days he just doesn't seem to be too much the genius.

Meg said...

I could only read the articles about the study and the abstract. The abstract speaks of IQ "relative to their peers", not actual IQ numbers. I am curious if the actual IQ number (WISC or SB) changed by 20 points or if they used some sort of relative scaled score. If IQ changed by 20 points in more than one subject, I would think that would have been a huge finding, calling into question the validity of IQ tests in general, and reported in the abstract. Also, no mention of what test they used for IQ (again only in the abstract).