Effective connectivity of the multiplication network: A functional MRI and multivariate granger causality mapping study

Abstract

Developmental neuropsychology and functional neuroimaging evidence indicates that simple and complex mental calculation is subserved by a fronto-parietal network. However, the effective connectivity (connection direction and strength) among regions within the fronto-parietal network is still unexplored. Combining event-related fMRI and multivariate Granger Causality Mapping (GCM), we administered a multiplication verification task to healthy participants asking them to solve single and double-digit multiplications. The goals of our study were first, to identify the effective connectivity of the multiplication network, and second, to compare the effective connectivity patterns between a low and a high arithmetical competence (AC) group. The manipulation of multiplication difficulty revealed a fronto-parietal network encompassing bilateral intraparietal sulcus (IPS), left pre-supplementary motor area (PreSMA), left precentral gyrus (PreCG), and right dorsolateral prefrontal cortex (DLPFC). The network was driven by an intraparietal IPS-IPS circuit hosting a representation of numerical quantity intertwined with a fronto-parietal DLPFC-IPS circuit engaged in temporary storage and updating of arithmetic operations. Both circuits received additional inputs from the PreCG and PreSMA playing more of a supportive role in mental calculation. The high AC group compared to the low AC group displayed a greater activation in the right IPS and based its calculation more on a feedback driven intraparietal IPS-IPS circuit, whereas the low competence group more on a feedback driven fronto-parietal DLPFC-IPS circuit. This study provides first evidence that multivariate GCM is a sensitive approach to investigate effective connectivity of mental processes involved in mental calculation and to compare group level performances for different populations.

Synchronization during an internally directed cognitive state in healthy aging and mild cognitive impairment: a MEG study

“…Here we showed that in both groups, delta connectivity was greater during mental calculation than in resting state, a finding in line with the previous literature. This increased connectivity between the left and right anterior regions indicates the necessity of the interaction between both hemispheres for the performance of mental calculation and could be engaged in updating of arithmetic operations and manipulation of information (Krueger et al 2011).…”

“…Conversely, there was a broad desynchronization in both groups in the IDICS task compared to resting state. This may reflect the activation of areas needed for calculation-such as the frontoparietal network (Krueger et al 2011)-or the deactivation of others that are able to adapt to the cognitive difficulty. Each factor could play a role in the successful execution of cognitive tasks.…”

Olfactory Network Differences in Master Sommeliers: Connectivity Analysis Using Granger Causality and Graph Theoretical Approach

“…This method is implemented using a multivariate autoregressive (MVAR) model. Several earlier studies have used these MVAR models based on the GC framework to study the predictive relationship between time series from different brain regions (Abler et al, 2006;Deshpande et al, 2011;Krueger et al, 2011;Lacey et al, 2011;Roebroeck et al, 2005).…”

Understanding economical outcomes with the mental number line

“…Authors reported that first-order and higher-order quantifiers both recruit right inferior parietal cortex, suggesting that a numerosity component contributes to quantifier comprehension. In fact, parietal activation was also widely reported in subjects asked to perform a simple number processing tasks [20,21,22,23,24] or arithmetic tasks [ 11,25,26].…”