'Dyscalculia' is different from 'bad in math'

Dyscalculia” makes it difficult for 5 to 8 percent of children to learn math, researchers estimate. These children are cognitively different from kids who just have trouble with math, a new study concludes. From Education Week:

A new, decade-long longitudinal study by researchers at the Kennedy Krieger Institute in Baltimore, published Friday in the journal Child Development, finds that 9th-graders considered dyscalculic—those who performed in the bottom 10 percent of math ability on multiple tests—had substantially lower ability to grasp and compare basic number quantities than average students or even other struggling math students.

“Formal math requires some effort, and it requires effort to different degrees for different children,” said Michèle M. M. Mazzocco, the director of the Math Skills Development Project at Kennedy Krieger. “Just because someone is having difficulty with math doesn’t necessarily mean they have a math learning disability. This study points to a core marker” of true dyscalculia.

Dyscalculia is about as common as dyslexia, researchers say. Yet there’s 20 times more research on reading problems than on math-learning disabilities.

Students with dyscalculia are significantly worse at estimating than other students, Mazzocco said.

“For [9th grade] children with math learning disability, there is precision at the level we would expect to see in a toddler or preschooler,” she said.

By contrast, there was no significant difference between students who performed in the low 10 to 25 percent of math ability and average-performing students, suggesting a difference in underlying causes of math problems for the lowest-performing students.

Brain-imaging studies of people estimating numbers have found lower brain activation in the parietal lobe for people identified with dyscalculia.

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  1. I’ve been following Mazzocco’s research for some time. Very fascinating stuff, and clearly distinguishes between slow learners and math learning disabled kids.

  2. I would like to see a better definition of dyscalculia than just “performs in the lowest 10%”. To me, there needs to be a discrepancy between general cognitive ability and math performance that cannot be accounted for by poor quality instruction.

    Not all dyscalculic students perform in the lowest 10%. And not all students who are in the lowest 10% are dyscalculic. Some may just have an overall low IQ.

  3. tim-10-ber says:

    Ok…I am a cynic…maybe we just have the kids slated to the wrong classes…last thing we need is another sped designation…

  4. Michael E. Lopez says:

    There are people who, as a result of a genetic defect, or adverse womb conditions, or early childhood developmental issues, cannot see.

    There are people who, as a result of a genetic defect, or adverse womb conditions, or early childhood developmental issues, cannot speak.

    There are people who, as a result of a genetic defect, or adverse womb conditions, or early childhood developmental issues, cannot hear.

    There are people who, as a result of a genetic defect, or adverse womb conditions, or early childhood developmental issues, cannot walk.

    I don’t find it surprising in the slightest that there are people who, as a result of a genetic defect, or adverse womb conditions, or early childhood developmental issues, cannot do math. I seriously doubt the frequency is as high as the article above suggests, but I don’t have a problem with the theory per se.

    On the other hand, despite listening to hours and hours of people talk at length about the subject, and despite the wealth of literature about dyslexia and it’s various treatments and so forth, I’m still relatively convinced that dyslexia is a symptom, and not a diagnosis of any meaningful kind.

    I suspect dyscalculia is quite similar.

  5. Richard Aubrey says:

    Count on the definition to expand.

  6. Oh goody! another friggin’ made-up disability just begging for an army of thumbsuckers to cater to it. I can already see the Math Ed folks gearing up to teach college-level courses in counting your fingers. Right behind them come the Food Nazis, who’ll jump on this to explain that discalcula leads to obesity due to Poor Portion Perception. Then come the financial regulators, the traffic safety gang, the FDA, the FTC, the PTA, etc. etc. This will be a research (and comedy) goldmine.

    Dollars to donuts (that’s 2:1 for you discalcics), most of these poor performers catch on just fine if their baby sister tries to short them on the split of the Halloween candy or a piece of cake.

    (cross-posted at The Random Texan)

  7. I’m with tin-10-ber and Mike Anderson on this one. If people are physically and mentally incapable of learning math, please please please let’s not require them to take two years of math, including Algebra 1, in order to graduate from high school.

  8. Michael E. Lopez says:


    The alternative is to give them a high school degree that doesn’t mean the same as it does for all the students who did meet the requirement… or are you just in favor of easing the graduation requirements rather than having differential requirements? (Which seems perfectly fine to me.) I would guess the former, but it’s not clear from your post.

  9. Sean Mays says:

    Interesting – should the Dyscalculate be barred from entering financial transactions? It could be argued that insurance, credit and mortgages require moderate math knowledge. How could I enter a legal contract for a product that requires math knowledge? Presumably they’ll not be able to determine how to save for retirement either. Oh wait, the Great Recession and the housing bubble; excuse my rant. Probably the incidence of dyscalculate is HIGHER than the researchers have estimated.

  10. Mike Anderson,

    So trained researchers spend over a decade studying this one topic, running tests and analyzing results, becoming experts in this field, and you have the temerity to through out a knee jerk reaction that just screams arrogance and ignorance. They have been working on this for a decade, yet you read a brief reference to it and then feel as if you are up to speed enough to call it “another friggin’ made up disability.” Where is your evidence for calling it “made up?” Do you actually have any, or are you just another one of those anti-science folks who think that they know everything, research and evidence be damned? Goodness.

  11. Swede–

    You called it with the knee-jerk ignorance quote. I’ve looked at the research these folks have been doing (go look it up for yourselves, folks; I’m not doing it for free) and yes, indeed, there’s some pretty strict criteria present.

    This team of researchers has identified at least two different types of math disability (as measured by the Woodcock-Johnson III NU Tests of Achievement); a calculation-type disability and a math reasoning-type disability. The effects and the prognosis for remediation map pretty closely to their reading equivalents (decoding and comprehension; calculation is more easily remedied and math reasoning has more significant long-term effects).

    And for those of you bemoaning yet another disability, no, that’s not it at all. What this research does is helps those of us who actually work with these kids more understanding of the disability and how best to remediate it. It’s a subset of Specific Learning Disability and students who have this particular disability are going to have already been identified with LD. Math calculation and math reasoning are already Federal categories under LD.

  12. Ah, “anti-science,” the summer replacement for “racist.” I’ve also been called Ugly and Poopy-Head. I’m rubber, you’re glue…

    The problem isn’t that some folks have different brain wiring that makes quantitative reasoning–as we have formalized it–difficult; that is only sensible to posit, explore, and understand. joycem has it right when talking about identification and remedy, if indeed remedy is possible and feasible. BTW, that brain scan stuff is scary–I’d be very interested to see how far along the researchers are in determining cause and effect. Could remediation change brain structure?

    The problem is that, like many other developmental problems, dyscalcula has the potential to be misunderstood, counfounded with shabby education, and abused by opportunists, and I fear our institutional response will be inadequate. I fully expect a wave of newly-discovered alleged dyscalcics to hit my university’s Disability Services in the next few years, endeavoring to dodge our pitiful undergraduate math requirement. Right behind them will be the Dyscalcula Therapists, who will urge a shotgun approach to retool every course and textbook containing a equation or column of numbers.

    Since we insist on preparing everyone for college, we then get to the Darren-Michael Problem. A goodly portion of STEM instructors and students will end up with dumbed-down curriculum, our goof-off students won’t even be able to find the buttons on their TI-89’s, and the truly dyscalcic will be left out in the cold. Nobody’s going to be happy; my jerky knee and I are just ahead of the curve.

  13. superdestroyer says:

    In the military book “Dirty Little Secrets” http://www.strategypage.com/dls/default.aspit was
    stated that about 25% of Americans cannot be taught to read a map and have no “sense” of direction. That is why the U.S Army and Marine Corps used to make map readings a must pass portion of becoming an officer.

    I suspect that the same people who cannot be taught to read a map are the people who just cannot be taught math.

  14. This is why we have people getting killed using their GPS or driving their cars into swamps. The overuse of technology has made people use their brains less, which isn’t a good thing. I use Google Maps to print a map for me for locations in the same area in which I live (within a 30 mile radius), and it doesn’t fail me because A), if I get lost, I can stop and ask for directions, and B) technology isn’t perfect.

  15. Superdestroyer said:

    I suspect that the same people who cannot be taught to read a map are the people who just cannot be taught math.

    Yep. There’s some pretty strong correlations between the two skills when it comes to brain processing. Visual processing and all that good fun stuff.

    Bill, I think the folks getting killed using their GPS would do the same even reading maps. One of the scariest “lost in the wilds” stories I read involved misreading (or not reading) maps, and that was in the 50s.

    Mike Anderson, the question about “can remediation change brain structure” is exactly the concern. We are still discovering what the limits are for neuroplasticity. It’s a thorny issue in neuroscience, and it’s kinda-sorta discussed. I’m scrambling to keep up with the field, but the sheer volume is overwhelming at the moment. It’s what I’m doing this summer.

  16. I suspect that the same people who cannot be taught to read a map are the people who just cannot be taught math.

    Nope, map-reading is a different skill than doing mathematical calculations. I am *HORRIBLE* at reading maps, but do fine in math aside from geometry & trig. Arithmetic, algebra, calculus- anything that relies on numbers and letters I can do fairly well. Reading a map, trying to fit a bunch of luggage into my trunk, playing Tetris- all these things rely on spatial reasoning & I stink at them.

    If you want me to arrive at a destination, tell me how to get there in words.

  17. Oh, and I *LOATHE* those d*** Ikea pictorial assembly directions. I have ceded all Ikea assembling over to my DH.

  18. For those of you who aren’t so familiary with dyscalculia there is a good series of videos on dyscalculia from UK expert Jane Emerson: http://www.dystalk.com/talks/32-what-is-dyscalculia

  19. Jill Bell says:

    Map reading and mathematical calculations are both mathematical skills, but it has to do with the difference between “global” and “organizational” math (terms that I have coined). Are some of you out there better at Geometry than Algebra? You are probably more of a global thinker – able to look at the big picture and decipher what parts are present (like map reading). Organizational thinkers (like myself) tend to understand math better when it’s presented in step by step instructions. Think about how you like to be given directions to a new destination – with a full map, or turn-by-turn instructions? That’s the difference…

  20. I agree with Keith Devlin’s theory that language was just one step along an evolutionary path that then led to mathematics (see _The Math Gene_). I would strongly suspect that kids with discalculia would also have poor language skills, since the same parts of the brain are involved.

  21. James Bailey says:

    Crimson Wife has it right. Map reading is a visual skill; old legacy maths like algebra and calculus are symbol-manipulation skills. Interestingly enough, the new maths used by ecologists and biologists are much more visual.

    Marshall McLuhan knew fifty years ago that suburban kids got most of their information symbolically (text) whereas city kids got most of theirs visually *(television.) Guess who is best prepared for an all-symbols-all-the-time maths curriculum. If we gave kids the choice of either the symbolic maths of astronomy and physics or the pattern-intensive maths of ecology and biology, we would be in a better place.

  22. I wrote about this last week at http://rightontheleftcoast.blogspot.com/2011/06/real-or-imagined-problem.html . Here’s a snippet:

    If this condition is real, mark my words–it will be overblown. How can it not be, it’s the greatest “Get out of jail free card” in the history of school. I dread the special education and disability accommodation nightmare that will occur when this diagnosis makes its way into the school system. Seriously, we may as well just give them all A’s (because that’s all too many parents want) just to shut them up, as people will be beating down the doors with IEPs and 504 Plans for dyscalculia.

    I would hope that if this diagnosis gains traction, California would eliminate its graduation requirement of passing Algebra 1. I don’t think it’s out of bounds to expect seniors to pass a class that Singaporeans pass in 7th grade, but if we’re going to have to water it down even more to pass the dyscalculics, it would be better just to be rid of the requirement.

  23. I don’t think students with dyscalculia will be beating down the doors to major in STEM fields any more than dyslexics are beating down the doors to major in the humanities. People know their strengths and weaknesses and tend to choose majors that emphasize the former and minimize the latter.

  24. I can only speak about a student I tutored in Math from 5th grade to 12th grade (she just graduated). My dear student Natalie has very little innate understanding of numbers. She definitely has learning disabilities – she has little innate understanding of phonics as well, but she does not have a low IQ. Her comprehension is excellent and lucky for her she has a very good memory. She has to think about 5 times 3 and even 9 plus 6 – very little comes easy. However, with my help, she has passed high school algebra, geometry and algebra 2. There is a name for her specific condition, but I can no longer remember it. What Natalie needed from day one is step-by-step instruction in phonics and math. She would have benefited from homeschooling, but that was not an option for her family. Unfortunately her private school’s way of dealing with her was only to give her accomodations rather than to actually teach her correctly. When she was with me calculators were NOT allowed! However, for a test I had to tell her to be sure to check everything with her calculator because she so easily would make simple mistakes (simple to most of us).

    Did Natalie belong in high school math classes? She persevered through something very difficult. Her brain made new connections through the work of conquering something challenging. She’d have never made it without a tutor and I’m glad I was available for her (not a wealthy family – I charge very little because I like to help my middle class neighbors).

  25. Jill Bell says:

    Darren said, “I would hope that if this diagnosis gains traction, California would eliminate its graduation requirement of passing Algebra 1. I don’t think it’s out of bounds to expect seniors to pass a class that Singaporeans pass in 7th grade, but if we’re going to have to water it down even more to pass the dyscalculics, it would be better just to be rid of the requirement.”

    Texas has the requirement that every student has to pass Algebra II in order to graduate – passing Algebra I is old school. But the way the schools are set up, the dyscalculia students (assuming they were diagnosed properly) would be IEP’d out of that requirement. It is stupid to lower the standards for all students just because a select few can’t cut it. Those kids get a different diploma. They say “every student,” but they mean “every student getting a standard diploma.”

  26. Cranberry says:

    I think kids who have dyscalculia would already be on an IEP. I’m listening to a Princeton University podcast at the moment. Stanislaus Dehaene, a French researcher, is speaking of his work. Basically, the true dyscalculics lack the sense most humans (including babies and, apparently, some animals) possess of the relative size of quantities. For example, the dyscalculics could look at pages of dots, but not be able to say instantly whether a group of 9 dots is larger than a group of 5 dots.

    As math education currently assumes that the learners possess an innate number sense, dyscalculics probably do terribly in math class. Once researchers have identified means to discern who is dyscalculic, then they can try to determine whether alternative methods of instruction make a difference in outcome. There may be nothing to improve the students’ performance. It could be similar to dyslexics, in that explicit, intense training in phonics can improve performance, particularly if begun at a young age. Or, it could be like trying to teach color blind people to distinguish between hues with intensive training. No matter how much time you spend at it, it isn’t going to happen.