Training arithmetical skills when finger counting and working memory cannot be used: A single case study in a child with cerebral palsy.

Children with cerebral palsy (CP) are at greater risk of mathematical learning disabilities due to associated motor and cognitive limitations. However, there is currently little evidence on how to support the development of arithmetic skills within such a specific profile. The aim of this single-case study was to assess the effectiveness of a neuropsychological rehabilitation of arithmetic skills in NG, a 9-year-old boy with CP who experienced math learning disability and cumulated motor and short-term memory impairments. This issue was explored combining multiple-baseline and changing-criterion designs. The intervention consisted of training NG to solve complex additions applying calculation procedures with a tailor-made computation tool. Based on NG's strengths, in accordance with evidence-based practice in psychology, the intervention was the result of a co-construction process involving N, his NG's parents and professionals (therapist and researchers). Results were analyzed by combining graph visual inspections with non-parametric statistics for single-case designs (NAP-scores). Analyses showed a specific improvement in NG's ability to solve complex additions, which maintained for up to 3 weeks after intervention. The training effect did not generalize to his ability to perform mental additions, and to process the symbolic magnitude.