www.diseases-diagnosis.com Homepage Diseases Symptoms Diseases Diagnosis Diseases Treatment Diseases Living Care Diseases Prevention Diseases Research
March 26, 2016
Table of Contents

1 Introduction



Acalculia (not to be confused with dyscalculia), from the Greek "a" meaning "not" and Latin "calculare", which means "to count",

is an acquired impairment in which patients have difficulty performing simple mathematical tasks, such as adding, subtracting, multiplying and even simply stating which of two numbers is larger. Acalculia is distinguished from dyscalculia in that acalculia is acquired late in life due to neurological injury such as stroke, while dyscalculia is a specific developmental disorder first observed during the acquisition of mathematical knowledge.

Acalculia is associated with lesions of the parietal lobe (especially the angular gyrus) and the frontal lobe and can be an early sign of dementia. Acalculia is sometimes observed as a "pure" deficit, but is commonly observed as one of a constellation of symptoms, including agraphia, finger agnosia and left-right confusion, after damage to the left angular gyrus, known as Gerstmann's syndrome (Gerstmann, 1940; Mayer et al., 1999).

Studies of patients with lesions to the parietal lobe have demonstrated that lesions to the angular gyrus tend to lead to greater impairments in memorized mathematical facts, such as multiplication tables, with relatively unimpaired subtraction abilities. Conversely, patients with lesions in the region of the intraparietal sulcus tend to have greater deficits in subtraction, with preserved multiplication abilities (Dehaene and Cohen, 1997). These double dissociations lend support to the idea that different regions of the parietal cortex are involved in different aspects of numerical processing.

  • Numerical cognition


  • "Acalculia." Stedman's Medical Dictionary, 27th ed. (2000). ISBN 0-683-40007-X

  • Dehaene, S., & Cohen, L. (1997). Cerebral pathways for calculation: Double dissociation between rote verbal and quantitative knowledge of arithmetic. Cortex , 33(2), 219-250.

  • Gerstmann, J. (1940). Syndrome of finger agnosia, disorientation for right and left, agraphia, acalculia. Archives of Neurology and Psychology 44, 398???408.

  • Mayer, E. et al. (1999). A pure case of Gerstmann syndrome with a subangular lesion. Brain 122, 1107???1120.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "acalculia".

Last Modified:   2010-12-02

All informatin on the site is © www.diseases-diagnosis.com 2002-2011. Last revised: January 2, 2011
Are you interested in our site or/and want to use our information? please read how to contact us and our copyrights.
To let us provide you with high quality information, you can help us by making a more or less donation: