The C-not-B error: a comparative study

Abstract

Fourteen 29-month-old children with type-2 spinal muscular atrophy (SMA) and 14 controls were presented with a 3-location search task involving the invisible displacements of an object. Results show that SMA children search correctly for a hidden object in this particular task, whereas healthy children emit a strong response bias toward the last hiding place. In order to test the hypothesis according to which healthy children’s failure is the consequence of an impulsive response, the time between the hiding of the toy and the child’s response was manipulated in a second experiment. The results show a dramatic increase in the healthy children’s performance. The discussion highlights the inhibitory mechanisms present in SMA children but underdeveloped in healthy children.