The Basic Facts
Dyscalculia is a specific learning disability in mathematics. Dyscalculia is a word you use to describe when people have significant problems with numbers - but still have a normal or above normal IQ. It seems that no dyscalculic has problems with math alone, but also struggle with problems being able to learn to tell time, left/right orientation, rules in games and much more. See the list of symptoms. Also, there are more types of dyscalculia, and all types demand specific learning   more...methods aimed at the specific problem.

Is Dyscalculia A Real Thing?
Dyscalculics say it is. Teachers say it is. WHO and DSM say it is. See the bottom of this page for the official listings of dyscalculia in the medical world.


How Common Is Dyscalculia?
According to UK studies done by Gross-Tsur, Manor and Shalev in 1996, 6.5% are dyscalculic. According to studies done by Lewis, Hitch and Walker in 1994, 1.3% are dyscalculic while 2.3% are dyscalculic AND dyslexic - that means that according to this study 3.6% of the World's population are dyscalculic.

That gives a total of between 3.6 and 6.5% of the World's population. And again: That means, according to these two studies, that between 216.000.000 (two hundred and sixteen million) and 390.000.000 (three hundred and ninety million) people are dyscalculic - if we say that there are 600.000.000.000 (six billion) people in the world. No international study has been done on how common it is.

What Is The Male/Female Prevalence?
Although dyslexia seems to have a take on the male population (30% female versus 70% male), when it comes to dyscalculia studies show that the representation is equal - 50% female, 50% male.

There Are Types Of Dyscalculia?
Yes. Just like in the case of dyslexia, there are more versions of dyscalculia. Researchers have yet to come to a final decision, and they are not working together, which means that at least over 50 types have been "discovered". We have guts here at the forum, so we have decided to stick with 4 types that make sense according to the forum users. These names are from a study done by Geary in 2004. You can read about the 4 types in the forums - there are subforums for each type, where we try to figure out all we can about the types.

Semantic retrieval dyscalculia
Procedural dyscalculia
Visuospatial dyscalculia
Number fact dyscalculia

Dys...Cal...Culia?
To pronounce it you say "dis-cal-cew-lee-ah". When a person has dyscalculia, you say that they are "dyscalculic" - "dis-cal-cew-leek".

The word dyscalculia comes from Greek and Latin and means "counting badly". The word "dys" comes from Greek and means "badly". "Calculie" comes from the Latin "calculare", which means "to count". The word "calculare" again comes from "calculus", which means "pebble" or one of the counters on an abacus. No one seems to know when the word "dyscalculia" to life - the earliest we have come across is this advertisement in The New York Times from May 1968. We do however know that researchers have used other words for what they found to be some sort of disability in maths (which they already found in the 1800s); arithmetic disability, arithmetic deficit, mathematical disability and so on. The media has been using words like digit dyslexia, number blindness and the obvious maths dyslexia.

Lots of variations of the word exist - Dyscalculi, discalculi, discalculia and so on. This seems to be spelling mistakes caused by general lack of knowledge about the disability, and the fact that no government has officially named the disability "dyscalculia", but instead goes by the WHO (specific disorder of arithmetical skills) and DSM (mathematics disorder) terms. Dyslexia is not officially named dyslexia either. In other words, dyslexia and dyscalculia are nicknames. It would be hard to say "specific disorder of arithmetical skills" every time you would mention this disability, wouldn't it?

"You Can If You Want To!"
Probably followed by "and if you try hard enough". This is a typical remark from teachers and parents to motivate the student - and although it can be meant in the BEST way possible, it is not true when it comes to dyscalculic students. The thing a dyscalculic wants most in this world is to be able to understand those numbers. Dyscalculics need different learning methods, in every aspect of the assignment. Dyscalculics are able to learn how to calculate something one day, only to discover that the information has been forgotten the next day. In other words programs like Kumon, where repetition is a major part of the teaching methods seem to have no result for dyscalculic students - they forget. Through different learning methods aimed specifically at the student and his/her version of dyscalculia can have great results.

DISCLAIMER: Kumon helps a lot of non-dyscalculic children around the world, and it is possible that some dyscalculic students are learning by Kumon - we have just never heard of any dyscalculic who benifited from these learning methods. Please let us know if YOU did.

What Is Acalculia?
Acalculia is caused by serious brain damage. While it is possible to learn maths when you have dyscalculia, it seems impossible when acalculia is the problem - there simply is no understanding for numbers at all; not even the simple task of counting to ten. Acalculia is listed in WHO ICD 10 under R48.8.

I Can't Find Dyscalculia In WHO or DSM
That's because dyscalculia is a nickname. Dyslexia is also a nickname. Somehow these names have been made up, and it does seem a lot easier than to say the correct names. These are the official listings of dyscalculia in DSM-IV and WHO ICD-10;

DSM-IV 315.1
Mathematics Disorder

The Diagnostic and Statistical Manual of Mental Disorders, otherwise known as DSM, is the standard classification of mental disorders used by mental health professionals in the United States and some countries in the Western world. It is published by the American Psych  less