11 Facts About the Math Disorder Dyscalculia


Chances are you’ve heard of the reading disability dyslexia. It reportedly affects up to 15 percent of the population, and public figures from the fictional Jaime Lannister in HBO’s Game of Thrones to real-life comic Eddie Izzard have grappled with the learning disorder. But have you ever heard of dyscalculia, the math disability? Probably not, even though up to six percent of elementary school students in the U.S. may struggle with it.

A big part of the general population's unfamiliarity with dyscalculia has to do with our culture’s general discomfort with numbers, and our ingrained belief that math—compared to reading—is just supposed to be hard. Dr. Gavin Price, an assistant professor at Vanderbilt University who has researched dyscalculia in several countries, says, "When I teach classes, I’ll ask at the beginning, 'How many people think they’re not good at math, they’re bad at math?' And half of them put their hands up. Then I ask, 'Are any of you bad at reading?' And nobody puts their hand up."

Dr. Edward Hubbard, an assistant professor at the University of Wisconsin-Madison, echoes this sentiment, and adds that attitudes toward math may play a part not just in our overall lack of dyscalculia awareness, but in the fact that dyscalculia research is at least two decades behind dyslexia research.

“I think some of it is cultural attitudes towards math,” says Hubbard, who has researched dyscalculia in France and the United States and heads up his university’s Educational Neuroscience lab, which is embarking on a new dyscalculia study. “If you look around, the number of people who sort of say, 'I’m bad at math,' and laugh about it, or will say, without batting an eye, 'I’m just not a math person,' is striking.”

So, in the interest of raising dyscalculia awareness, begin your crash course on the little-known mathematical disorder with these 11 facts.

1. The term dyscalculia was coined in the 1940s, but didn’t really become fully recognized until the 1974 work of Czechoslovakian researcher Ladislav Kosc.

Kosc defined the disorder as "a structural disorder of mathematical abilities" caused by impairment to the parts of the brain used in mathematical calculations, without simultaneous impairment to one's general mental abilities. (In layman's terms: You're bad at math because parts of your brain aren't working properly, but you're not otherwise mentally handicapped.) Today, some research communities also use the terms “math dyslexia” and “math learning disability” to refer to the condition.

2. There are two types of dyscalculia.

Most people diagnosed with the disorder have developmental dyscalculia, which means they were born with it. But, with what's known as acquired dyscalculia, the disorder can also arise later in life, usually as the result of a stroke or injury.

3. Struggling with matrices in algebra or flunking calculus in college doesn’t usually mean you have dyscalculia.

This disability tends to impede your most basic skills. “Somebody who has dyscalculia will struggle with the most basic arithmetic facts, 5+2=7,” Hubbard says. “They will struggle to tell you seven is larger than five. We’ll see them counting on their fingers for basic addition.”

4. Dyscalculia may be rooted in the brain's parietal lobe.

What causes dyscalculia? To date, the most popular theory maintains that dyscalculia is connected to an inability to judge quantities, a sense that is concentrated in the parietal lobe.

“One of the theories that exists is that dyscalculia is really caused by an impairment in what’s known as either the number sense or the approximate number system,” Price says. “And that system is what allows us to know that, for example, a group of five apples is more than three apples. It allows us to compare, and order, and process quantities without the use of verbal symbols or labels."

"And so what we did [in a study in Finland]," Price continues, "was scan these dyscalculic kids while they were doing those type of tasks, and we compared their brain activation to the typically developing kids, and we found that indeed this region in the parietal cortex, the intraparietal sulcus, behaved atypically in these kids when they were processing these non-symbolic numerical magnitudes.”

5. Researchers have been able to induce dyscalculia in patients.

In 2007, a group of researchers at University College London were able to engender temporary dyscalculia in people who don’t have the disorder by using transcranial magnetic stimulation, or TMS. TMS is often used to treat depression, and involves placing a large electromagnetic coil against the scalp.

In the study, researchers applied TMS to the right parietal lobe while their subjects were comparing quantities, and found that the stimulation briefly made it hard for the subject to tell if one quantity was bigger than the other.

6. Dyscalculia may manifest itself in different ways. 

While the above research shows that dyscalculia is closely associated with problems in the parietal lobe that affect one's understanding of the number system, researchers like Hubbard think some people who suffer from dyscalculia might feel the disorder differently.

“The problem may not be with number sense itself, but with linking number symbols with number sense,” Hubbard says. “Maybe it differs across other people. Maybe there is a subgroup of people for whom their difficulties are in the number system itself, for other people it’s in symbols.” 

7. Dyscalculia is represented in pop culture.

While dyslexic characters are much more common in popular culture, there are some examples of dyscalculics to be found. Fans of Canadian teen drama Degrassi: The Next Generation may remember Liberty Van Zandt having it, and X-Men fans may know that Wolverine's sidekick Jubilee is a whiz at manipulating pyrotechnics but not numbers.

8. Dyscalculia doesn't discriminate by gender.

You may have noticed that both our pop culture examples were female, but dyscalculia, at least at this juncture, does not appear to have a gender gap.

“My sense is that it’s pretty even. But at the same time, I feel like the gender ratio has been less a focus of investigation than it was for dyslexia,” Hubbard says, adding that research saying boys are more prone to dyslexia than girls is “pretty well supported.”

Hubbard is aware that this flies in the face of the (offensive) stereotype that women are worse at math than men—a generalization that seems to have little basis in fact. “What we see is that the gender differences [in mathematical ability] have gotten smaller and smaller. As we have better role models for girls in math, we’ve had greater opportunities and fewer impediments to girls being able to do well. The differences that we’re seeing are largely due to cultural differences.”

9. However, some groups are at greater risk of dyscalculia than others.

People with Turner syndrome, epilepsy, and Fragile X syndrome are more likely to have dyscalculia. You are also at greater risk for dyscalculia if you have attention deficit hyperactivity disorder (ADHD), if your mother drank during her pregnancy, or if you were born prematurely.

10. It can be tough to diagnose.

“One of the problems, one of the challenges with dyscalculia, the reason that it hasn’t gotten the same attention [as dyslexia], is that it is a highly co-morbid disorder,” Price says. “Often, people who are bad at math are bad at a number of things.”

But while a diagnosis may be difficult to come by, treating a patient's other conditions may also alleviate his or her dyscalculia. For example, one study of people with ADHD who both were and weren’t dyscalculic found that putting them on a stimulant improved their calculating ability, but not their basic numerical skills.

11. There is no cure for dyscalculia.

But don't lose hope! Dyscalculics can learn math, even if they may always struggle with parts of it because of their neurological differences. Luckily, you use more than the parietal part of your brain when doing math, Price says. “Multiple skills come under the umbrella of math, and all of these things will engage all of the lobes of the brain.”

Therefore, early detection is key in helping children cope with dyscalculia. And for adults struggling with the disorder, a shift in attitude may be the first step in overcoming the obstacles dyscalculia presents.

“When we think of struggling with reading, most adults would not think of going back and listening to the sounds of language,” Hubbard says. “Similarly, if you recognize that you’re struggling with math, your first thought isn’t probably that you should go back to trying to see how much stuff is out there, use this basic sense of number that I have, and try to link that to basic number symbol. People would probably try to work at a higher level. What you should really be doing is going back and looking at these foundational skills, things that most teachers, most parents, and most people assume we all just have.”

12 Creative Ways to Spend Your FSA Money Before the Deadline

stockfour/iStock via Getty Images
stockfour/iStock via Getty Images

If you have a Flexible Spending Account (FSA), chances are, time is running out for you to use that cash. Depending on your employer’s rules, if you don’t spend your FSA money by the end of the grace period, you potentially lose some of it. Lost cash is never a good thing.

For those unfamiliar, an FSA is an employer-sponsored spending account. You deposit pre-tax dollars into the account, and you can spend that money on a number of health care expenses. It’s kind of like a Health Savings Account (HSA), but with a few big differences—namely, your HSA funds roll over from year to year, so there’s no deadline to spend it all. With an FSA, though, most of your funds expire at the end of the year. Bummer.

The good news is: The law allows employers to roll $500 over into the new year and also offer a grace period of up to two and a half months to use that cash (March 15). Depending on your employer, you might not even have that long, though. The deadline is fast approaching for many account holders, so if you have to use your FSA money soon, here are a handful of creative ways to spend it.

1. Buy some new shades.

Head to the optometrist, get an eye prescription, then use your FSA funds to buy some new specs or shades. Contact lenses and solution are also covered.

You can also buy reading glasses with your FSA money, and you don’t even need a prescription.

2. Try acupuncture.

Scientists are divided on the efficacy of acupuncture, but some studies show it’s useful for treating chronic pain, arthritis, and even depression. If you’ve been curious about the treatment, now's a good time to try it: Your FSA money will cover acupuncture sessions in some cases. You can even buy an acupressure mat without a prescription.

If you’d rather go to a chiropractor, your FSA funds cover those visits, too.

3. Stock up on staples.

If you’re running low on standard over-the-counter meds, good news: Most of them are FSA-eligible. This includes headache medicine, pain relievers, antacids, heartburn meds, and anything else your heart (or other parts of your body) desires.

There’s one big caveat, though: Most of these require a prescription in order to be eligible, so you may have to make an appointment with your doctor first. The FSA store tells you which over-the-counter items require a prescription.

4. Treat your feet.

Give your feet a break with a pair of massaging gel shoe inserts. They’re FSA-eligible, along with a few other foot care products, including arch braces, toe cushions, and callus trimmers.

In some cases, foot massagers or circulators may be covered, too. For example, here’s one that’s available via the FSA store, no prescription necessary.

5. Get clear skin.

Yep—acne treatments, toner, and other skin care products are all eligible for FSA spending. Again, most of these require a prescription for reimbursement, but don’t let that deter you. Your doctor is familiar with the rules and you shouldn’t have trouble getting a prescription. And, as WageWorks points out, your prescription also lasts for a year. Check the rules of your FSA plan to see if you need a separate prescription for each item, or if you can include multiple products or drug categories on a single prescription.

While we’re on the topic of faces, lip balm is another great way to spend your FSA funds—and you don’t need a prescription for that. There’s also no prescription necessary for this vibrating face massager.

6. Fill your medicine cabinet.

If your medicine cabinet is getting bare, or you don’t have one to begin with, stock it with a handful of FSA-eligible items. Here are some items that don’t require a prescription:

You can also stock up on first aid kits. You don’t need a prescription to buy those, and many of them come with pain relievers and other medicine.

7. Make sure you’re covered in the bedroom.

Condoms are FSA-eligible, and so are pregnancy tests, monitors, and fertility kits. Female contraceptives are also covered when you have a prescription.

8. Prepare for your upcoming vacation.

If you have a vacation planned this year, use your FSA money to stock up on trip essentials. For example:

9. Get a better night’s sleep.

If you have trouble sleeping, sleep aids are eligible, though you’ll need a prescription. If you want to try a sleep mask, many of them are eligible without a prescription. For example, there’s this relaxing sleep mask and this thermal eye mask.

For those nights you’re sleeping off a cold or flu, a vaporizer can make a big difference, and those are eligible, too (no prescription required). Bed warmers like this one are often covered, too.

Your FSA funds likely cover more than you realize, so if you have to use them up by the deadline, get creative. This list should help you get started, and many drugstores will tell you which items are FSA-eligible when you shop online.

10. Go to the dentist.

While basics like toothpaste and cosmetic procedures like whitening treatments aren’t FSA eligible, most of the expenses you incur at your dentist’s office are. That includes co-pays and deductibles as well as fees for cleanings, x-rays, fillings, and even the cost of braces. There are also some products you can buy over-the-counter without ever visiting the dentist. Some mouthguards that prevent you from grinding your teeth at night are eligible, as are cleaning solutions for retainers and dentures.

11. Try some new gadgets.

If you still have some extra cash to burn, it’s a great time to try some expensive high-tech devices that you’ve been curious about but might not otherwise want to splurge on. The list includes light therapy treatments for acne, vibrating nausea relief bands, electrical stimulation devices for chronic pain, cloud-connected stethoscopes, and smart thermometers.

12. Head to Amazon.

There are plenty of FSA-eligible items available on Amazon, including items for foot health, cold and allergy medication, eye care, and first-aid kits. Find out more details on how to spend your FSA money on Amazon here.

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9 Things Invented By Accident

These sugary summer treats were an accidental invention.
These sugary summer treats were an accidental invention.
Daniel Öberg, Unsplash

Not every great invention was created according to plan. Some, in fact, were the result of a happy accident. In November 2020, the pharmaceutical company AstraZeneca announced that the COVID-19 vaccine it had developed in partnership with Oxford University was 90 percent effective when administered in a dosing regimen they had discovered thanks to some “serendipity.” This wasn't the only unintentional discovery in history, of course. From penicillin to artificial sweeteners, all nine of the everyday items below were invented entirely by accident.

1. Penicillin

On September 28, 1928, Scottish scientist Alexander Fleming discovered that a petri dish of staphylococcus bacteria that had been inadvertently left out on the windowsill of his London laboratory had become contaminated by a greenish-colored mold—and encircling the mold was a halo of inhibited bacterial growth. After taking a sample and developing a culture, Fleming discovered that the mold was a member of the Penicillium genus, and the rest, as they say, is history.

2. Corn Flakes

The two Kellogg brothers—Dr. John Harvey Kellogg and his younger brother (and former broom salesman) Will Keith Kellogg—worked at Battle Creek Sanitarium in Michigan, where John was physician-in-chief. Both were strict Seventh-day Adventists, who used their work at the sanitarium to promote the austere dietary and moralist principles of their religion (including strict vegetarianism and a lifelong restraint from excessive sex and alcohol) and to carry out research into nutrition, and the impact of diet on their patients. It was during one of these experiments in 1894 that, while in the process of making dough from boiled wheat, one of the Kelloggs left the mash to dry for too long and when it came time to be rolled out, it splintered into dozens of individual flakes. Curious as to what these flakes tasted like, he baked them in the oven—and in the process, produced a cereal called Granose. Some later tinkering switched out the wheat for corn, and gave us corn flakes.

3. Teflon

Polytetrafluoroethylene—better known as PTFE, or Teflon—was invented by accident at a DuPont laboratory in New Jersey in 1938. Roy Plunkett, an Ohio-born chemist, was attempting to make a new CFC refrigerant when he noticed that a canister of tetrafluoroethylene, despite appearing to be empty, weighed as much as if it were full. Cutting the canister open with a saw, Plunkett found that the gas had reacted with the iron in the canister’s shell and had coated its insides with polymerized polytetrafluoroethylene—a waxy, water-repellent, non-stick substance. Du Pont soon saw the potential of Plunkett’s discovery and began mass producing PTFE, but it wasn’t until 1954, when the wife of French engineer Marc Grégoire asked her husband to use the same substance to coat her cookware to stop food sticking to her pans, that the true usefulness of Plunkett’s discovery was finally realized.

4. Slinky

In 1943, naval engineer Richard T. James was working at a shipyard in Philadelphia when he accidentally knocked a spring (that he had been trying to modify into a stabilizer for sensitive maritime equipment) from a high shelf. To his surprise, the spring neatly uncoiled itself and stepped its way down from the shelf and onto a pile of books, and from there onto a tabletop, and then onto the floor. After two years of development, the first batch of 400 “Slinky” toys sold out in just 90 minutes when they were demonstrated in the toy department of a local Gimbels store in 1945.

5. Silly Putty

At the height of World War II, rubber was rationed across the United States after Japan invaded a number of rubber-producing countries across southeast Asia and hampered production. The race was on to find a suitable replacement—a synthetic rubber that could be produced inside the U.S. without the need of overseas imports, which eventually led to the entirely unexpected invention of Silly Putty. There are at least two rival claims to the invention of Silly Putty (chiefly from chemist Earl L. Warrick and Scottish-born engineer James Wright), both of whom found that mixing boric acid with silicone oil produced a stretchy, bouncy rubber-like substance that also had the unusual ability of leaching newspaper print from a page (an ability that changing technology has now eliminated).

6. Post-It Notes

Pexels, Pixabay

In 1968, a 3M chemist named Dr. Spencer Silver was attempting to create a super-strong adhesive when instead he accidentally invented a super-weak adhesive, which could be used to only temporarily stick things together. The seemingly limited application of Silver’s product meant that it sat unused at 3M (then technically known as Minnesota Mining & Manufacturing) for another five years, until, in 1973, a colleague named Art Fry attended one of Silver’s seminars and struck upon the idea that his impermanent glue could be used to stick bookmarks into the pages of his hymnbook. It took another few years for 3M to be convinced both of Fry and Silver’s idea and of the salability of their product, but eventually they came up with a unique design that worked perfectly: a thin film of Spencer’s adhesive was applied along just one edge of a piece of paper. After a failed test-market push in 1977 as Press ’N Peel, the product went national as the Post-It note in 1980.

7. Saccharin

In 1878 or '79 (sources differ), Constantin Fahlberg, a chemist studying the properties of oxidized coal tar at Johns Hopkins University in Baltimore, Maryland, discoveredwhile eating his meal one evening that food he picked up with this fingers tasted sweeter than normal. He traced the sweetening effect back to the chemical he had been working with that day (Ortho-sulfobenzoic Acid Imide, no less) and, noting its potential salability, quickly set up a business mass producing his sweetener under the name Saccharin. Although quickly popular (and equally quickly controversial), it would take the sugar shortages of two World Wars to make the discovery truly universal.

8. Popsicles

The first popsicle was reportedly invented by 11-year-old Frank Epperson in 1905, when he accidentally left a container of powdered soda and water, with its mixing stick still inside, on his porch overnight. One unexpectedly cold night later, and the popsicle—which Epperson originally marketed 20 years later as an Epsicle—was born.

9. Safety glass

Safety glass—or rather, laminated glass—was accidentally discovered by the French chemist Édouard Bénédictus when he knocked a glass beaker from a high shelf in his laboratory and found, to his surprise, that it shattered but did not break. His assistant informed him that the beaker had contained cellulose nitrate, a type of clear natural plastic, that had left a film on the inside of the glass. He filed a patent for his discovery in 1909, and it has been in production (albeit in various different forms) ever since.