Is the Brain Like a Muscle, Really?

Back in 2007, Ashley and I reported on the science of praise for New York magazine, highlighting in particular the body of work by Dr. Carol Dweck. Dweck had done studies for over a decade – and we covered them all – including a brand new semester-long intervention that had been conducted with Lisa Blackwell at Life Sciences Secondary School in East Harlem.

Life Sciences is a health-science magnet school with high aspirations but 700 students whose main attributes are being predominantly minority and low achieving. The scholars split the kids into two groups for an eight-session workshop. The control group was taught study skills, and the others got study skills and a special module on how intelligence is not innate. These students took turns reading aloud an essay on how the brain grows new neurons when challenged. They saw slides of the brain and acted out skits. After the module was concluded, Blackwell tracked her students' grades to see if it had any effect.

It didn't take long. The students who had been taught that intelligence can be developed improved their study habits and grades. In a single semester, Blackwell reversed the students' longtime trend of decreasing math grades.

The only difference between the control group and the test group were two lessons, a total of 50 minutes spent teaching not math but a single idea: that the brain is a muscle. Giving it a harder workout makes you smarter. That alone improved their math scores.

Ever since that New York magazine story was published, it's been common now to tell kids the brain is like a muscle, and intelligence is malleable. The catch was that the students at Life Sciences were reading a four-page middle-reader version of neuroscience-lite that was somewhat edited to enhance, or sell, the idea that IQ isn't fixed.

So it's been a legitimate ongoing question whether we're really now telling kids the truth, when we tell the brain is a muscle. Just how malleable is IQ, really? Are we misleading them at all, when we suggest their IQ is something they can control?

As Ashley and I wrote in NurtureShock, children's IQs do change a lot as they develop. More than half of children will see significant swings in their IQ – not just once, but three times. And the swings are not minor. Two-thirds of children's IQ scores improve, or drop, more than 15 points. One-third of kids' scores jump more than 30 points. So there's clearly a lot of instability going on.

But does that give us license to suggest to kids their brains can really be altered, quickly? Are we lying to them if we ignore there's some element of genetic predestination?

Well, that's why yesterday's column here was, we believe, so important. Drs. Silvia Bunge and Allyson Mackey set up a special afterschool program at a low-performing elementary school in Oakland. For eight weeks, twice a week, kids came into one of two rooms to play board games, video games, and card games. These are games available at most retailers, but they'd been chosen by Bunge and Mackey because they demanded very specific cognitive skills. One set of games – in one room – challenged the kids' reasoning ability. The other set of games – in the other room – challenged those kids' processing speed.

Before and after the training, the scholars measured relevant components of the children's IQs. The scholars expected some modest improvement. But the results were staggering – the group that trained for reasoning ability saw their non-verbal intelligence scores leap 32%. The group that trained for processing speed saw their brain speed scores jump 27%. In just eight weeks – 20 hours total of training – the games had a drastic impact on the kids' IQ.

Now, Mackey does warn that kids who already come from enriched home environments might already have these games, or something similar, and in many ways they might have already trained their brains. So while Mackey suspects all kids could benefit from the game training, not all kids would benefit so much, so quickly.

Nevertheless, it's striking evidence that indeed, the brain is like a muscle. While every individual probably has upper limits to what we might be capable of, brain training – like weight training, or fitness training – can lift us towards those limits.

(Check yesterday's column for links to the games.)

Uncommon Knowledge

Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.

Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.

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