A math learning disability similar to dyslexia affects 6 percent of people, although it gets little attention.
“Dyscalculia” is discussed in Discover Magazine as excerpted below:
“Steph Zech graduated from high school this spring with an admirable academic record. She especially loved chemistry, writing and literature — though she has some reservations about Dante. A bright and diligent student, she took two Advanced Placement classes her senior year, sailing through both.
“But when it comes to math, Steph has struggled mightily. At age 17, she still counts on her fingers to add 3 and 5. She doesn’t know her multiplication tables. She can’t understand fractions, process concepts of time such as “quarter after” or read dice without counting the dots. She did recently figure out that if something costs 75 cents, the change from a dollar should be 25 cents. But when asked what the change would be if the price were 70 cents, she considers at length before venturing, “15 cents?”
“There are many reasons for a bright student to be bad at math, including poor learning environments, attention disorders and anxiety. But Steph’s struggles typify a specific math learning disability known as developmental dyscalculia. “A lot of people say, ‘I’m not good at math’ because they couldn’t handle pre-calculus or something,” says cognitive neuroscientist Edward Hubbard of the University of Wisconsin-Madison. “People with dyscalculia struggle to tell you whether seven is more than five.”
“Although dyscalculia, which affects about 6 percent of people, is about as common as the analogous reading disorder dyslexia, it is far less well-understood. According to one analysis, studies on reading disabilities outnumber those that look at math deficits by a ratio of 14 to 1. One reason for that disparity may be the belief that literacy is more important than numeracy.”