Acquired procedural dyscalculia associated to a left parietal lesion in a child.
We report the case of an 11-year-old boy who developed an anarithmetia in association with a left temporo-parietal tumor. His oral and written language were normal as well as his ability to judge magnitudes, process numbers, read operation signs and retrieve number facts. He had a specific difficulty in performing the procedures of subtraction, especially when it involved borrowing. These skills had been mastered before the present illness. This case shows that the components of calculation can be dissociated by brain lesions sustained during childhood, while arithmetic abilities are being acquired, thus reinforcing findings from developmental dyscalculias, that suggest a modular organisation of those skills during development.
Language Research Laboratory, Centro de Estudos Egas Moniz, Hospital de Sta Maria, Lisboa, Portugal. labling@mail.telepac.pt
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Martins
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Ferreira
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Borges
D001932:Brain Neoplasms / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D002648:Child; D005500:Follow-Up Studies; D006801:Humans; D007859:Learning Disabilities / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D009483:Neuropsychological Tests; D009837:Oligodendroglioma / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D010296:Parietal Lobe / Q000503:physiopathology* / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D011340:Problem Solving / Q000502:physiology*; D012086:Reoperation