Why Math and Reading Skills Usually (But Don’t Always) Go Hand-In-Hand

Do you remember second grade reading groups? They had nifty names like redbirds, bluebirds, and goldfinches to keep us from discovering who was in a “high” group and who was in a “low” group. As if! It took about four seconds to realize the redbirds were cruising through chapter books while the bluebirds sounded out words. It didn’t help to keep the secret that pretty much the same kids were grouped together in math, too. And this points to a great, unfair truth in education: smart kids tend to be smart across the board, whereas kids who struggle in reading tend to also struggle in math.

Of course, there are exceptions. Not everybody who is good at math is also good at reading (and vice versa). But there’s an ability underlying these two skills. A paper by researchers at Vanderbilt University scheduled for publication in the journal Child Development pinpoints this One Ability To Rule Them All but also shows what else goes into math or reading skills. Yes, math and reading are poured from the same fount of brainy goodness… but then there are other unique skills that flavor the two cups.

Their study is both ambitious and powerful, following 747 kids from first through third grades and testing them along the way to discover their paths. There’s some obvious stuff: kids who started with high reading skills in large finished with high reading skills. The same was true of math: most of the third graders who were good at math had also been good at math in first grade. (They point to this as evidence that a child’s academic trajectory can be largely fixed very early…)

But then there’s this whole mix of skills that may have no effect on their own, but combine Voltron-like to create this great, umbrella ability that makes the redbirds in reading also the redbirds in math. That skill is memory retrieval. It’s made up of sub-skills including attentive behavior, reasoning, working memory, visuospatial memory, and something called rapid automatized naming (basically, how quickly you can recall the word “apple” when presented with a picture of an apple). Notice it’s not exactly the same thing as general intelligence–“smart” kids are probably better at reading and math, but it’s a special kind of smarts that prioritizes the packing and unpacking of memory that really does the trick.

“This suggests that competent third-grade calculation and word-reading performance both rely on the ability to form and ?uently retrieve from memory arbitrary associations between the visual symbolic and phonological forms,” the paper writes. This was especially true for math skills: This One Skill To Rule Them All trumped the influence of any single skill on the development of math ability.

Here’s an example of how this works: attentive behavior does not directly predict which kids will be good at reading. But this attentive behavior tends to boost kids’ memory retrieval, which in turn boosts reading. If somehow attentive behavior didn’t help a child sow and reap from his or her memory, it wouldn’t necessarily do squat for his or her reading.

Then there are skills that even taken piecemeal boost reading or math. Here are the skills that boost reading: language, phonological memory, rapid automatized naming. Here are the skills that boost math: attentive behavior, working memory, reasoning. Notice that there is no overlap! Outside the underlying ability of memory retrieval, math and reading are different skills.

So now we’ve got two things going on. We’ve got a pool of skills that create memory retrieval, boosting both reading and math together, and we’ve got individual skills that boost one or the other but not both. We’ve also got at least a preliminary answer to a longstanding question in education: why do so many kids do well or poorly in both reading and math, but also why do some kids break this mold?

The answer is that kids who are good at both very likely depend on this skill of memory retrieval–this high tide floats both boats. Kids who are good only at reading might be a little lower in memory retrieval (allowing them to under perform in math), but probably have one or more of the special reading skills of language, phonological memory, or rapid automatized naming. Likewise, kids who are only good at math might lack the One Skill To Rule Them All, but have special prowess in attentive behavior, working memory, and/or reasoning.

In a vastly oversimplified but nonetheless compelling and thought-provoking nutshell, that’s why most kids are good or bad at both reading and math, but some kids can buck the trend to excel at only one.