Developmental changes in California Card Sorting Test performance.

The purpose of the present study was to determine 1) if performance on the California Card Sorting Test (CCST) follows the same developmental gradient as other measures of concept formation and 2) whether the components of concept formation tapped by the CCST are developmentally dissociable. Participants were 68 children and young adults in four age-based groups: 7 to 9 years (n = 13); 10 to 12 years (n = 16); 17 to 19 (n = 20); and, 20 to 22 years (n = 19). All were of average or higher measured intelligence and screened for neurological, psychiatric, reading and attentional disorder. The findings of the present study suggest that like many other concept formation tasks, CCST performance approximates adult levels by age 10. Further, the different components of concept formation measured by the CCST are dissociable in the youngest children with the development of concept recognition preceding sorting ability.