Changes in Functional Connectivity of Default Mode Network with Auditory and Right Frontoparietal Networks in Poststroke Aphasia
| Autor: | Alexey Petrushevsky, Olga Martynova, V.V. Balaev |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Male
Functional Laterality 050105 experimental psychology Brain Ischemia White matter 03 medical and health sciences 0302 clinical medicine Parietal Lobe Aphasia Neural Pathways mental disorders Healthy volunteers medicine Humans 0501 psychology and cognitive sciences In patient Default mode network Aged Aged 80 and over Auditory Cortex Brain Mapping Neuronal Plasticity medicine.diagnostic_test General Neuroscience Functional connectivity 05 social sciences Magnetic resonance imaging Middle Aged Magnetic Resonance Imaging Frontal Lobe Stroke medicine.anatomical_structure Right superior Female medicine.symptom Psychology Neuroscience 030217 neurology & neurosurgery |
| Zdroj: | Brain Connectivity. 6:714-723 |
| ISSN: | 2158-0022 2158-0014 |
| Popis: | 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 interest-based 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 gyrus, 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. |
| Databáze: | OpenAIRE |
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