White matter integrity and core cognitive function in children diagnosed with sickle cell disease.

Children diagnosed with sickle cell disease (SCD) have an increased risk of stroke, often associated with white matter damage and neurocognitive morbidity. Growing evidence suggests that subtle changes in white matter integrity, which do not pass the threshold to be visible on a clinical magnetic resonance image and classified as stroke, may contribute to decreased cognitive performance. We used archived diffusion-weighted imaging and neurocognitive assessment data to identify associations between microstructural changes in normal-appearing white matter and cognitive performance in children with SCD.

Responses and sustained interactions in children with mental retardation and autism.

Sustained interactions and responses to social bids made by children with autism and verbal-age-matched children with mental retardation were recorded in two naturalistic settings. Children with autism produced fewer positive responses and more "no responses" than children with mental retardation; both groups were more likely to make positive responses to adults and not to respond to other children. Furthermore, although the frequency of conversations was not different for the two groups, children with autism were significantly less likely to engage in sustained play compared to children with mental retardation.