Resting-state network topology and planning ability in healthy adults

Odile A. van den Heuvel,Ysbrand D. van der Werf,Margot J. Wagenmakers,Chris Vriend

doi:10.1007/s00429-019-02004-6

Abstract

Functional magnetic resonance imaging (fMRI) studies have been used extensively to investigate the brain areas that are recruited during the Tower of London (ToL) task. Nevertheless, little research has been devoted to study the neural correlates of the ToL task using a network approach. Here we investigated the association between functional connectivity and network topology during resting-state fMRI and ToL task performance, that was performed outside the scanner. Sixty-two (62) healthy subjects (21–74 years) underwent eyes-closed rsfMRI and performed the task on a laptop. We studied global (whole-brain) and within subnetwork resting-state topology as well as functional connectivity between subnetworks, with a focus on the default-mode, fronto-parietal and dorsal and ventral attention networks. Efficiency and clustering coefficient were calculated to measure network integration and segregation, respectively, at both the global and subnetwork level. Our main finding was that higher global efficiency was associated with slower performance (β = 0.22, Pbca = 0.04) and this association seemed mainly driven by inter-individual differences in default-mode network connectivity. The reported results were independent of age, sex, education-level and motion. Although this finding is contrary to earlier findings on general cognition, we tentatively hypothesize that the reported association may indicate that individuals with a more integrated brain during the resting-state are less able to further increase network efficiency when transitioning from a rest to task state, leading to slower responses. This study also adds to a growing body of literature supporting a central role for the default-mode network in individual differences in cognitive performance.

Highlights

Executive functions are a set of mental processes that enable us to plan, focus attention, remember instructions and handle several tasks at once (Diamond 2013)
In this study in 62 healthy adults with a wide age range we investigated the association between network topology during a rs-Functional magnetic resonance imaging (fMRI) session and cognitive planning ability during a Tower of London (ToL) task that was performed outside the scanner
We observed that global efficiency was associated with reduced planning speed and that this effect was mainly driven by the functional connectivity (FC) of the default mode network (DMN)

Summary

Introduction

Executive functions are a set of mental processes that enable us to plan, focus attention, remember instructions and handle several tasks at once (Diamond 2013). The brain balances its ability to integrate and transmit information throughout the network, and to segregate information processing in clusters of highly interconnected (specialized) neighboring nodes (Bullmore and Sporns 2009). This ability of the brain for integration and segregation is vital for cognitive processes (Cohen and D’Esposito 2016) and higher intelligence has been associated with a more efficient network topology (Langer et al 2012; van den Heuvel et al 2009). Based on prior research (Langer et al 2012; van den Heuvel et al 2009; Sheffield et al 2017), we hypothesized a positive relationship between network topology measured during restingstate and cognitive planning ability, measured using the ToL task performed outside of the scanner

Methods

Results

Conclusion