General Intelligence Is Associated with Working Memory-Related Functional Connectivity Change: Evidence from a Large-Sample Study

Abstract

BACKGROUND/PURPOSE\nPsychometric intelligence is closely related to working memory (WM) and the associated brain activity. We aimed to clarify the associations between psychometric intelligence and WM-induced functional connectivity changes.\n\n\nMETHODS\nHere we determined the associations between psychometric intelligence measured by non-verbal reasoning (using the Raven s Advanced Progressive Matrix) and WM-induced changes in functional connectivity during the N-back paradigm, in a large cohort of 1221 young adults.\n\n\nRESULTS\nWe observed that the measures of general intelligence showed a significant positive correlation with WM-induced changes in the functional connectivity with the key nodes of the fronto-parietal network, such as the bilateral premotor cortices and the pre-SMA. Those significant correlations were observed for (a) areas showing a WM-induced increase of the functional connectivity with the abovementioned key nodes, such as the lateral parietal cortex, (b) areas showing a WM-induced decrease of the functional connectivity with the abovementioned key nodes, (b-1) such as left perisylvian areas and cuneus, the fusiform gyrus, and the lingual gyrus, which play key roles in language processing, (b-2) hippocampus, and parahippocampal gyrus, which play key roles in memory processing, and (b-3) the key node of the default mode network such as the medial prefrontal cortex as well as (c) the border areas between (a) and (b).\n\n\nCONCLUSION\nPsychometric intelligence is associated with WM-induced changes in functional connectivity, influencing the way in which WM key nodes dynamically modulate the interaction with other brain nodes in response to WM.