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;
