Background. The relationship between auditory-verbal short-term memory (AVSTM) and calculation is controversial. Impaired arithmetic abilities have been reported in patients with defective AVSTM, but a double dissociation between calculation skills and STM has been found in other patients with developmental and acquired disorders (Butterworth, Campbell and Howard 1986; Butterworth, Cipollotti and Warrington 1996). In the present study, we report an improvement in calculation abilities following specific rehabilitation in a case of developmental dyslexia (BM's) associated with defective AVSTM. Case report. BM is a left-handed, 25-year-old male with 8 years of education. In primary school, BM started having problems in learning to read and was given remedial teaching. BM's full-scale IQ on the WAIS was 90 (verbal IQ 78, non-verbal IQ 106, arithmetic subtest 4). His digit span was 3 forward and 2 backward; his word span was 2. A detailed, general neuropsychological examination was otherwise normal. BM was also submitted to a detailed number processing and calculation evaluation (Miceli and Capasso 1991): the overall performance indicated a severe deficit. In particular, in subtraction problems BM failed to use the borrow procedure: he consistently applied the 'smaller-from-larger' bug. Results. A significant improvement in number processing and calculation was observed after the training period. In contrast, the training did not affect mental calculation and repetition tasks. Conclusion. The present case supports for the hypothesis of the link between defective auditory-verbal STM and acalculia, though an association of deficits should be treated with caution. Furthermore, it shows that partial improvement in number processing can be obtained by specific rehabilitation, with the exception of the procedures putatively related with STM, such as mental calculation.
|Issue number||4 SUPPL.|
|Publication status||Published - 2000|
ASJC Scopus subject areas
- Clinical Neurology