Paper Info
Title
Changes in Functional Connectivity of Default Mode Network with Auditory and Right Frontoparietal Networks in Poststroke Aphasia.
Abstract
To evaluate the influence of poststroke aphasia on the functional association of widespread large-scale neuronal networks, we analyzed functional connectivity (FC) between resting-state brain networks (RSNs) in aphasic patients (N = 15) and in healthy volunteers (N = 17) of the same age using resting-state functional connectivity magnetic resonance imaging. As a result, six RSNs were isolated and cross-correlation matrices were computed for their time courses. Aphasic patients showed decreased correlations between posterior part of the default mode (pDMN) and both auditory (AUD) and right frontoparietal (RFP) networks. Additionally, we calculated regions of interestbased FC (ROI-FC), gray and white matter volumes in the ROIs overlapping with pDMN, AUD, and RFP. ROI-FC analysis showed decreased FC between the right pars triangularis and both right middle frontal and right superior frontal gyri. The decreased pDMN-RFP connectivity in patients is likely to reflect changes in FC of these nodes. The lesion in the regions overlapping with pDMN and AUD networks leads to the significantly decreased pDMN-AUD connectivity. Our results suggest that abnormal FC in stroke patients may reflect the impairment of activity not only in the regions directly affected by stroke lesion in the left hemisphere but also in the homotopic regions of the intact right hemisphere. The increase of gray and white matter volume in the right supramarginal gyms, the functional hub of pDMN, AUD, and RFP networks, correlated with less speech impairment. This increase might reflect a right hemisphere neuroplasticity process to compensate the impaired function of the homotopic region of left frontoparietal network (LFP), pDMN, and AUD in the left hemisphere. The presented results contribute to the hypothesized compensative role of the transfer of attention and executive functions from the damaged areas in the left hemisphere to the right homotopic areas, accompanied by more preserved language skills at the chronic stroke stage.
Year
DOI
Venue
2016
10.1089/brain.2016.0419
BRAIN CONNECTIVITY
Keywords
Field
DocType
aphasia (language),resting-state functional connectivity magnetic resonance imaging,resting-state networks,stroke
Default mode network,Right superior,Neuroscience,White matter,Pars triangularis,Stroke,Aphasia,Medicine,Magnetic resonance imaging
Journal
Volume
Issue
ISSN
6
9
2158-0014
Citations 
PageRank 
References 
1
0.37
0
Authors
3
Name
Order
Citations
PageRank
Vladislav Balaev110.71
Alexey Petrushevsky210.37
Olga Martynova310.37