Directed corticocortical functional connectivity at the early stages of serial learning in adults and seven- to eight-year-old children

Abstract

Serial learning at its earlier stages, presumably involving the working memory, was studied in adults and seven- to eight-year-old children during the reproduction of a sequence of discrete movements following the order specified by a sequence of visual stimuli. In both age groups, the learning curves (latent time vs. trial number) were qualitatively similar in shape. The overall shape of the learning curve depended on the relative proportion of the fast vs. slow phases of latent time reduction. Comparison of the corticocortical functional connectivity patterns in the prestimulus period in the sequence reproduction task vs. the simple visuomotor reaction task showed a general tendency of an increase in the influence of postcentral cortical areas accompanied by the reduced influence of prefrontal and central cortical areas. In particular, it was typical of adults to show an increase in the directed influence of temporo-parieto-occipital (TPO) cortical areas, while the children also showed an increase in the directed influence of the parietal cortex. Comparison of the subgroups with different shapes of learning curves in the prestimulus period has shown the difference in their patterns of directed functional connectivity. The results are discussed with a special emphasis on the role of the working memory retaining the internal representations of sequences being learned.