Frontal lobe lesions and executive dysfunction in children

Objective: To investigate the relationship of frontal lobe lesions and neuropsychologic performance in school-aged children to determine whether damage to frontal regions results in specific cognitive sequelae. Background: The role of the frontal lobes in executive function remains incompletely understood, particularly in children. Method: This retrospective study included children aged 8 to 17 with brain lesions of various etiology (n = 63) or diverse psychiatric disorders (n = 48). All were evaluated for details of neurologic and medical history and for scores on the Wechsler Intelligence Scale for Children (WISC-III) and the Wisconsin Card Sorting Test, and all but the psychiatric patients had neuroimaging scans. Five groups were analyzed - dorsolateral frontal, medial-orbital frontal, focal nonfrontal, diffuse, and psychiatric - and neuropsychologic test results were compared using a Kruskal-Wallis nonparametric analysis of variance. Results: Children with damage to dorsolateral frontal regions were more impaired on the Wisconsin Card Sorting Test than those in all other groups. Comparable performance on the Wechsler scale was found in all groups, suggesting that intellectual functioning did not account for this difference. Conclusions: These data provide evidence for a prominent role of the dorsolateral frontal regions in the mediation of executive function in children. They also support the use of the Wisconsin Card Sorting Test in children as a measure of dorsolateral frontal integrity.