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Biomedical subjects

U Kirk

Publications and source records attributed to U Kirk.

7 recordsLinked to original sources

Effects of age on neurocognitive measures of children ages 5 to 12: a cross-sectional study on 800 children from the United States.

The standardization of the NEPSY-A Developmental Neuropsychological Assessment (Korkman, Kirk, & Kemp, 1998) provided an opportunity to study the effects of age across the age range 5 to 12 years. Test scores of 800 children on 20 subtests of NEPSY were analyzed. These measures are based on traditions of neuropsychological assessment and are thought to reflect attention and executive functions, language, sensorimotor functions, visuospatial functions, and memory and learning. The effects of age were very significant on all measures, confirming the developmental sensitivity of the NEPSY. The effects of age were more significant in the 5- to 8-year age range than in the 9- to 12-year range. Only performance on tasks of fluency and memory span for sentences showed significant age effects in the 10- to 12-year age range. This suggests that neurocognitive development is rapid in the 5- to 8-year age range and more moderate in the 9- to 12-year age range.

Age Factors↗

Cognitive processing deficits in reading disabilities: a prefrontal cortical hypothesis.

Much research investigating the neuropsychological underpinnings of reading disabilities has emphasized posterior brain regions. However, recent evidence indicates that prefrontal cortex may also play a role. This study investigated cognitive processes that are associated with prefrontal and posterior brain functions. Subjects were 12-year-old reading disabled and nondisabled boys. Discriminant analysis procedures indicated that measures of prefrontal functions distinguished between the two groups better than measures of posterior functions. The results suggest that reading disabled boys have difficulty with cognitive processes involving selective and sustained attention, inhibition of routinized responses, set maintenance, flexibility in generating and testing alternative hypotheses, and phonemically based language production.

Attention↗