| Turner syndrome, a genetic disorder affecting girls, has a well described neurocognitive profile including difficulty with visual-spatial processing and attention skills. The goal of the current study was to investigate executive function and attention abilities in females with Turner Syndrome (TS). Executive skills include the ability to plan, organize, monitor, and execute multi-step problem solving processes. Measures of attention, visual-spatial and perceptual skills, language, and executive function were analyzed from 130 girls with Turner Syndrome and from 208 female controls matched for age, IQ, and SES. Three age groups were evaluated in order to assess developmental patterns in executive skills. TS girls performed at levels comparable to controls on tasks involving hypothesis generation and mental flexibility (e.g., the Wisconsin Card Sort Test), but demonstrated relative difficulty on a measure of verbal fluency, and on measures involving working memory (e.g., Tower of Hanoi) and organizational components (e.g., Rey-Osterrieth organization). While age-related improvement was demonstrated on all measures of executive function, no interactions were found between age and study group. TS girls showed a developmental trend relative to controls on the WCST that may suggest a developmental lag in the acquisition of efficient hypothesis testing. In consideration of developmental factors of executive function identified in normal controls, TS females performed at comparable levels to controls, and it is likely that these developmental factors do not accurately describe executive function in TS females. Because of the functional heterogeneity of executive function in children and adolescents, the explanation for these findings is uncertain. One possible explanation is that the difficulty in executive function may be due in part to weaknesses in visual-spatial planning and organization, and/or to weaknesses in attention. As results suggest TS females may demonstrate a weakness in verbal fluency as well, further exploration of the performance of TS females on executive tasks that minimize involvement of previously described TS associated deficits is warranted. Future investigation will enable us to more thoroughly understand the contribution of multi-modal factors, and the resulting neurocognitive profile, in individuals with Turner Syndrome. |
