Students struggle in math for a variety of reasons. The notion that all math difficulties can be grouped under one term, dyscalculia, is simplistic and misleading. Cognitive scientists have multiple theories of why students struggle in math and what cognitive processes are responsible for math deficits. Here is a brief summary of current research:

- Dehaene (1999) conducted a series of behavioral and brain-imaging experiments that provides evidence that mathematical intuition depends on both linguistic competence and visuo-spatial representations. These experiments demonstrated that exact calculation is language-dependent, while approximation relies on nonverbal visuo-spatial cerebral networks of the left and right parietal lobe. Dehaene makes the case that the innate ability of the human brain for approximation conflicts with the requirements for calculation and problem solving, both of which are mediated by language. Therefore, calculation and higher level mathematics is inherently more difficult than other cognitive processes (Holt, 2008).
- Geary (1993, 2000) proposed three categories of math disabilities.
- Semantic memory – a deficit in semantic memory occurs frequently with reading disorders. This group has difficulty with math fact retrieval.
- Procedural skills – This group uses immature procedures, such as counting on fingers. They make errors in carrying out procedures, sequencing multi-step procedures, and have delays in understanding concepts.
- Visuospatial deficits – This group misaligns numerals, misinterprets place value, and has great difficulty with geometry.

- Butterworth (2001, 2005) disputes Geary’s theory of semantic memory as a cause of a math disability. However, he notes that there is high co-morbidity of math disabilities and reading disabilities.
- Jordan (2003) found that children with both reading and math disabilities fell further behind as they progressed through school than did children who had a math disability only.
- In a recent review of the research on math deficits, Swanson (2006) concluded that memory problems related to math facts in children with a math deficit may reflect a poor coordination of information in the executive system, which fails in turn to retrieve numerical information in storage. This processing difficulty may reflect a working memory system that is either not accessing enough numerical information from the phonological system or failing to provide an adequate capacity for processing information.

### References

Dehaene, S., Spelke, E., Pinel, P., Stanescu, R., Tsivkin, S. (1999). Sources of mathematical thinking: Behavioral and brain-imaging evidence. *Science, (284)*, 970-974. Retrieved January 3, 2008 from www.sciencemag.org.

Holt, J. (2008, March 3). The Numbers guy. *The New Yorker, 84*(3), 42-47.

Ives, B. and Hoy, C. (2003). Graphic organizers applied to higher-level secondary mathematics. *Learning Disabilities Research and Practice*, 18(1), 36-51.

Geary, D.C. (1993). Mathematical disabilities: Cognitive, neuropsychological, and genetic components. *Psychological Bulletin, 114*, 345-362.

Geary, D.C. (2000). From infancy to adulthood: The development of numerical abilities. *European Child and Adolescent Psychiatry, 9*(2), 11–16.

Jordan, N. and Hanich, L. (2003). Characteristics of children with moderate mathematics deficiencies: A longitudinal perspective. *Learning Disabilities Research and Practice, 18*(4), 213-221.