Structural efficiency within a parieto-frontal network and cognitive differences

Here we compute the association between cognitive differences and variations in brain efficiency within a predefined structural network. The regions comprised by the network of interest were selected according to the parieto-frontal integration theory (P-FIT) (Jung & Haier, 2007). Local and global efficiency was quantified for this network. The former reflects specialization within the network, whereas the latter benefits long-distance interactions and reflects integration over the whole network. Fluid reasoning, working memory capacity, and processing speed were the measured cognitive factors. Forty-two young healthy women were the participants in the present study. These were the main findings: a) the precuneus, the middle frontal gyrus, the pars triangularis, and the superior frontal gyrus showed the greatest connectivity indices, supporting the special role of discrete parietal and frontal regions within the network, b) network efficiency was remarkably related with variations in working memory capacity, c) fluid reasoning showed positive correlations with network efficiency, and d) processing speed was unrelated with network efficiency. The findings underscore brain network analyses for studying cognitive differences.