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Dyscalculia[p] or math disability is a specific learning disability or difficulty involving innate difficulty in learning or comprehending mathematics. It is akin to dyslexia and can include confusion about math symbols. Dyscalculia can also occur as the result of some types of brain injury.
Dyscalculia was originally identified, in case studies, with patients who suffered specific arithmetic disabilities as a result of damage to specific regions of the brain. Recent research suggests that dyscalculia can also occur developmentally, as a genetically-linked learning disability which affects a person's ability to understand, remember, or manipulate numbers or number facts (e.g., the multiplication tables). The term is often used to refer specifically to the inability to perform arithmetic operations, but it is also defined by some educational professionals and cognitive psychologists as a more fundamental inability to conceptualize numbers as abstract concepts of comparative quantities (a deficit in "number sense"). Those who argue for this more-constrained definition of dyscalculia sometimes prefer to use the technical term "Arithmetic Difficulties" (AD) to refer to calculation and number memory deficits.
Dyscalculia is a lesser known disability, similar and potentially related to dyslexia and developmental dyspraxia. Dyscalculia occurs in people across the whole IQ range, and sufferers often, but not always, also have difficulties with time, measurement, and spatial reasoning. Current estimates suggest it may affect about 5% of the population. Although some researchers believe that dyscalculia necessarily implies mathematical reasoning difficulties as well as difficulties with arithmetic operations, there is evidence (especially from brain damaged patients) that arithmetic (e.g. calculation and number fact memory) and mathematical (abstract reasoning with numbers) abilities can be dissociated. That is (some researchers argue) an individual might suffer arithmetic difficulties (or dyscalculia), with no impairment of, or even giftedness in, abstract mathematical reasoning abilities.
The word dyscalculia comes from Greek and Latin which means: "counting badly". The prefix "dys" comes from Greek and means "badly". "Calculia" comes from the Latin "calculare". which means "to count". That word "calculare" again comes from "calculus", which means "pebble" or one of the counters on an abacus.
Dyscalculia can be detected at a young age and measures can be taken to ease the problems faced by younger students. The main problem is understanding the way mathematics is taught to children. In the way that dyslexia can be dealt with by using a slightly different approach to teaching, so can dyscalculia. However, dyscalculia is the lesser known of these learning disorders and so is often not recognized.
- Frequent difficulties with arithmetic, confusing the signs: +, −, ÷ and ×.
- Difficulty with everyday tasks like checking change and reading analog clocks.
- Inability to comprehend financial planning or budgeting, sometimes even at a basic level; for example, estimating the cost of the items in a shopping basket or balancing a checkbook.
- Difficulty with multiplication-tables, and subtraction-tables, addition tables, division tables, mental arithmetic, etc.
- May do fairly well in subjects such as science and geometry, which require logic rather than formulae, until a higher level requiring calculations is obtained.
- Difficulty with conceptualizing time and judging the passing of time. May be chronically late.
- Particularly problems with differentiating between left and right.
- Difficulty navigating or mentally "turning" the map to face the current direction rather than the common North=Top usage.
- Having particular difficulty mentally estimating the measurement of an object or distance (e.g., whether something is 10 or 20 feet (3 or 6 metres) away).
- Often unable to grasp and remember mathematical concepts, rules, formulae, and sequences.
- An inability to read a sequence of numbers, or transposing them when repeated, such as turning 56 into 65.
- Difficulty keeping score during games.
- Difficulty with games such as poker with more flexible rules for scoring.
- Difficulty in activities requiring sequential processing, from the physical (such as dance steps) to the abstract (reading, writing and signaling things in the right order). May have trouble even with a calculator due to difficulties in the process of feeding in variables.
- The condition may lead in extreme cases to a phobia or durable anxiety of mathematics and mathematic-numeric devices/coherences.
- Low latent inhibition, i.e., over-sensitivity to noise, smell, light and the inability to tune out, filtering unwanted information or impressions. Might have a well-developed sense of imagination due to this (possibly as cognitive compensation to mathematical-numeric deficits).
Scientists have yet to understand the causes of dyscalculia. They have been investigating in several domains.
- Neurological: Dyscalculia has been associated with lesions to the supramarginal and angular gyri at the junction between the temporal and parietal lobes of the cerebral cortex.
- Deficits in working memory: Adams and Hitch argue that working memory is a major factor in mental addition. From this base, Geary conducted a study that suggested there was a working memory deficit for those who suffered from dyscalculia. However, working memory problems are confounded with general learning difficulties, thus Geary's findings may not be specific to dyscalculia but rather may reflect a greater learning deficit.
Other causes may be:
- Short term memory being disturbed or reduced, making it difficult to remember calculations.
- Congenital or hereditary disorders. Studies show indications of this, but the evidence is not yet concrete.
Counselling can help, but not necessarily to a large degree. No therapy has been properly verified and proven to be effective. Some anecdotal evidence suggests, however, that a certain amount of mathematical proficiency can be acquired by alternative systems of mathematical calculation such as Eastern mathematics. Anecdotal evidence also suggests, in fact, that dyscalculic individuals might themselves pursue such systems out of need or interest. The condition need not be seen as a disability, there is nothing preventing people who suffer from dyscalculia from succeeding in other academic fields such as history, geography and other social sciences, or in artistic fields such as music or drama.
- [p] - The word dyscalculia can be pronounced either as "dis-cal-qu-lee-ah" or "dis-kal-KOOL-ee-ah".
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- ^ "What is Dyscalculia?", web: Dys-A2Z-Discalc.
- ^ How the Brain Learns Mathematics, David A. Sousa, 2007, p. 179 of 244 pages, web: Books-Google-t4C.
- Abeel, Samantha, 2003. My Thirteenth Winter. Orchard Books. ISBN 0-439-33904-9
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