Frontal lobe function and executive skills in children with turner's syndrome

Children with Turner's syndrome (TS), a sex chromosome abnormality in which the second X chromosome is abnormal or deleted, were given a series of tasks that investigated executive skills traditionally considered to be subserved by the frontal lobes. The children with TS showed significant deficits in comparison to controls but the effects were task specific. They were impaired on the Stroop, Verbal Fluency and the abstract version of the Self‐Ordered Pointing task. However, performance was entirely normal on the Wisconsin Card Sorting Test, the Tower of London and the concrete version of the Self‐Ordered Pointing task. These results support the fraction‐ability of executive control processes in development, thereby contradicting Fodor's (1983) conception of the absence of modularity in such systems. The phenotype‐genotype relation for 45,XO TS differed significantly from that of other karyotypes on the Self‐Ordered Pointing task, confirming the distinctive nature of aspects of the cognitive development of children with TS associated with differing etiological genotypes.