Context: The aim was to further understand the heterogeneity of developmental dyscalculia (DD). Utilizing four children (8-9 year-old) performance was contrasted against predominant hypotheses of DD. Case report: Despite showing similar mathematical deficits, these children showed remarkable inter-individual variability regarding cognitive profile and deficits. Two cases were consistent with the approximate number system deficit account, and the general magnitude-processing deficit account. One case had an access deficit in combination with a general cognitive deficit. One cases suffered from general cognitive deficits only. Conclusion: The results showed that DD cannot be attributed to a single explanatory factor. These findings support a multiple deficits account of DD and suggest that some cases have multiple deficits, whereas other cases have a single deficit. We discuss a previously proposed distinction between primary DD and secondary DD, and suggest hypotheses of dysfunctional neurocognitive correlates responsible for the displayed deficits.
Ulf Träff, Linda Olsson, Rickard Östergren and Kenny Skagerlund
Journal of Childhood & Developmental Disorders received 504 citations as per google scholar report