Numbers may be manipulated and represented mentally over a compressible number line oriented from left to right. According to numerous studies, one of the primary reasons for dyscalculia is related to improper understanding of the mental number line. Children with dyscalculia usually show difficulty when they have to place Arabic numbers on a…

Time perception has not been comprehensively examined in mathematics difficulties (MD). Therefore, verbal time estimation, production, and reproduction were tested in 13 individuals with MD and 16 healthy controls, matched for age, sex, and intellectual skills. Individuals with MD performed comparably to controls in time reproduction, but showed a…

The article describes a diagnostic procedure for assessing children's mental images and knowledge of cardinal numbers, 0 through 9. The diagnostic procedure includes the assessment of a child's visual memory, visual perception, symbol recognition, oral naming of numerals, and symbol-set linkage. (Author/SBH)

A definition of developmental dysalculia, stressing the hereditary or congenital affection of the brain substrate of mathematical functions, is put forth. (Author)