Dyscalculia

Dyscalculia
Specialty	Psychiatry, neuropsychology

Dyscalculia (not to be confused with acalculia) is defined as a specific neurological disorder affecting a person's ability to understand and/or manipulate numbers. Dyscalculia can be caused by a visual perceptual deficit. Dyscalculia is often used to refer specifically to the inability to perform operations in math or arithmetic, but is defined by some educational professionals as a more fundamental inability to conceptualize numbers themselves as an abstract concept of comparative quantities. It is a lesser known disability, much like and potentially related to dyslexia and dyspraxia. Dyscalculia occurs in people across the whole IQ range, but means they often have specific problems with mathematics, time, measurement, etc. Dyscalculia (in its more general definition) is not rare. Many of those with dyslexia or dyspraxia have dyscalculia as well. There is also some evidence to suggest that this type of SpLD is partially hereditary.

The word dyscalculia comes from Greek and Latin which means: "counting badly". The prefix "dys" comes from Greek and means "badly". "Calculie" 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 is a math impairment which often goes together with a number of other restrictions, such as spatial insight, reading time, poor memory, and orthography problems. There are indications that it is a congenitally hereditary impairment, with a neurological context. Dyscalculia concerns both children and adults.

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 types of learning disorders and so is often not recognized.

Potential symptoms

• Frequent difficulties with numbers, confusing the signs: +, -, ÷ and x.
• Problems differentiating between left and right.
• Having a poor sense of direction (i.e. north, south, east, and west) and may also have trouble still even with a compass.
• Inability to say which of two numbers is the larger.
• Reliance on 'counting-on' strategies, e.g. using fingers, rather than any more efficient mental arithmetic strategies.
• Difficulty with times-tables, mental arithmetic, etc.
• Does better in subjects such as science and geometry, which require logic rather than formulas, until a higher level requiring calculations is needed.
• Difficulty with conceptualizing time and judging the passing of time.
• 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.
• Having difficulty mentally estimating the measurement of an object or distance (e.g., whether something is 10 or 20 feet away).
• Inability to grasp and remember mathematical concepts, rules, formulae, and sequences.
• Difficulty keeping score during games.
• Difficulty in activities requiring sequential processing, from the physical (such as dance steps) to the abstract (reading, writing and signalling 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 of mathematics and mathematical devices (e.g. numbers).

Potential causes

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^[1][2].
• Deficits in working memory: Adams and Hitch^[3] argue that working memory is a major factor in mental addition. From this base, Geary^[4] 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.

Studies of mathematically gifted students has shown increased EEG activity in the right hemisphere during algorithmic computational processsing. There is some evidence of right hemisphere deficits in dyscalculia.

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 it is not yet concrete.
• A combination of these factors.

See also

• Gerstmann syndrome: dyscalculia is but one symptom.
• The DSM-IV diagnosis mathematics disorder can be applied to people whose mathematical abilities are well below the expected level for their age.
• Dyslexia
• Dysgraphia

External links

• 'The Mathematician Who Can't Add Up' Emma King Freeview Snapshot video by the Vega Science Trust.
• Nature Article
• Guardian Article
• Mathematics and Dyslexia
• LD Online
• DyscalculiaForum.com - International support forum
• Dyscalculia or acalculia
• Dyscalculia.org Symptoms of dyscalcula

Further reading

• Henderson Anne, Came Fil, Brough Mel. "Working with Dyscalculia." [5] Learning Works International Ltd, 2003, ISBN 0-9531055-2-0)
• Butterworth, Brian. "Dyscalculia Guidance: Helping Pupils With Specific Learning Difficulties in Maths." (David Fulton Pub, 2004, ISBN 0-7087-1152-9)
• Chinn, Steve. "The Trouble with Maths: A Practical Guide to Helping Learners with Numeracy Difficulties." (RoutledgeFalmer, 2004, ISBN 0-415-32498-X)
• Attwood, Tony. "Dyscalculia in Schools: What It Is and What You Can Do." (First and Best in Education Ltd, 2002, ISBN 1-86083-614-3)
• Abeel, Samantha. "My Thirteenth Winter." (Orchard Books, 2003, ISBN 0-439-33904-9)

References

1. ^ Levy LM, Reis IL, Grafman J. Metabolic abnormalities detected by 1H-MRS in dyscalculia and dysgraphia. Neurology. 1999;53(3):639—41. PMID 10449137
2. ^ Mayer E, Martory MD, Pegna AJ, Landis T, Delavelle J, Annoni JM. Free Full Text A pure case of Gerstmann syndrome with a subangular lesion. Brain. 1999;122(6):1107—20. PMID 10356063
3. ^ Adams JW, Hitch GJ. Working memory and children's mental addition. J Exp Child Psychol. 1997;67(1),21—38. PMID 9344485
4. ^ Geary DC. Mathematical disabilities: cognition, neuropsychological and genetic components. Psychol Bull. 1993;114(2) 345—62. PMID 8416036