These authors contributed equally to this work.
Effective connectivity of the multiplication network: A functional MRI and multivariate granger causality mapping study
Article first published online: 16 AUG 2010
Copyright © 2010 Wiley-Liss, Inc.
Human Brain Mapping
Volume 32, Issue 9, pages 1419–1431, September 2011
How to Cite
Krueger, F., Landgraf, S., van der Meer, E., Deshpande, G. and Hu, X. (2011), Effective connectivity of the multiplication network: A functional MRI and multivariate granger causality mapping study. Hum. Brain Mapp., 32: 1419–1431. doi: 10.1002/hbm.21119
- Issue published online: 11 AUG 2011
- Article first published online: 16 AUG 2010
- Manuscript Accepted: 4 JUN 2010
- Manuscript Revised: 2 JUN 2010
- Manuscript Received: 23 JUL 2009
- Georgia Research Alliance
- NIH. Grant Number: EB002009
- dorsolateral prefrontal cortex;
- intraparietal sulcus;
- mathematical competence;
- Granger causality
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. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc.