Introduction: Offsprings from a prenatal docosahexaenoic acid (DHA) supplementation trial, in which pregnant women were assigned to placebo or 600mg DHA/day, were followed to determine the effect of prenatal DHA supplementation on the behavior and brain function at 5.5 years (n=81 placebo, n=86 supplemented).Methods: Event-related potentials (ERP) were recorded during a visual task requiring a button press (Go) to frequent target stimuli and response inhibition to the rare stimuli (No-Go). Univariate ANOVAs were used to test differences between group and sex for behavioral measures. ERP differences were tested using a three-way mixed-design multivariate analysis of variance (MANOVA).Results: There was a significant sex × group interaction for hit rate and errors of omission; there was no difference between males and females in the placebo group, but DHA males outperformed DHA females. Males overall and the placebo group made more errors requiring response inhibition; DHA females were significantly better than placebo females and DHA males. ERP P2 amplitude was larger in the DHA group. A significant N2 amplitude condition effect was observed in females and DHA group males, but not in placebo group males.Discussion: Prenatal DHA supplementation improved inhibitory performance overall, especially for females in the DHA group, possibly accounting for their conservative behavior during Go trials. Development of brain regions responsible for visual processing may be sensitive to maternal DHA status, evidenced by greater P2 amplitude. Males may benefit more from maternal DHA supplementation, indicated by the N2 condition effect seen only in males in the DHA group.
Keywords: Docosahexaenoic acid; attention; brain; developmental programing, clinical trial; event-related potentials; inhibition; long-chain polyunsaturated fatty acids; prenatal nutrition.