Effects of Nutrition on the Development of Higher-Order Cognition
The long-chain polyunsaturated fatty acids (LC-PUFAs) docosahexaenoic acid (DHA) and arachidonic acid (ARA) occur in high levels in the brain and play a key role in brain growth and the operation of neurotransmitters. Infants supplemented with DHA show improved language and communication skills, and there is accumulating evidence that early development of executive functions such as planning, working memory, and attention control are influenced by LC-PUFAs, especially DHA. Several studies have found significantly improved means-end problem solving at 9 and 10 months in infants given DHA/ARA-supplemented formula, and similar results were shown for infants whose mothers were supplemented with DHA during pregnancy and breast feeding. Long-term benefits of LC-PUFA supplementation in infancy have been reported in children aged 3 to 6 years. Follow up studies of infants given DHA/ARA-supplemented versus control formula have shown better performance on tests of impulsivity and attention control in the supplemented children, with some indication of a dose-response relationship for DHA. In contrast, the results of studies with typically developing older children have been mixed, with many showing no effects of LC-PUFAs on cognition. However omega-3 supplementation of children with ADHD has been shown to provide a modest reduction in symptoms, and children scoring low on tests of reading ability have also shown improvement after supplementation with DHA.