Default mode network abnormalities in idiopathic generalized epilepsy

NYU Comprehensive Epilepsy Center, New York University School of Medicine, New York, NY, USA.
Epilepsy & Behavior (Impact Factor: 2.26). 02/2012; 23(3):353-9. DOI: 10.1016/j.yebeh.2012.01.013
Source: PubMed


Idiopathic generalized epilepsy (IGE) is associated with widespread cortical network abnormalities on electroencephalography. Resting state functional connectivity (RSFC), based on fMRI, can assess the brain's global functional organization and its disruption in clinical conditions. We compared RSFC associated with the 'default mode network' (DMN) between people with IGE and healthy controls. Strength of functional connectivity within the DMN associated with seeds in the posterior cingulate cortex (PCC) and medial prefrontal cortices (MPFC) was compared between people with IGE and healthy controls and was correlated with seizure duration, age of seizure onset and age at scan. Those with IGE showed markedly reduced functional network connectivity between anterior and posterior cortical seed regions. Seizure duration positively correlates with RSFC between parahippocampal gyri and the PCC but negatively correlates with connectivity between the PCC and frontal lobe. The observed pattern of disruption provides evidence for integration- and segregation-type network abnormalities and supports aberrant network organization among people with IGE.

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Available from: Jonathan Young, Jun 11, 2015
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    • "In both types neuronal loss spreads appear to follow white matter connections [2] which are the basis of structural connectivity brain networks. Epilepsy is known to be highly network-dependent [3] [4]. In [5] it is shown that local hubs in epileptic brains increases the likelihood of developing hyperexcitability . "
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    International Symposium on Biomedical Imaging, New York, USA; 04/2015
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    • "(Xue et al., 2014; Zhang et al., 2011)) and the observed functional differences (e.g. (McGill et al., 2012; Moeller et al., 2010)) in patients (see section 2 for further information). Computational modelling could be the key to advancing our understanding of the link between the abnormalities in structure and function. "
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    Journal of Neuroscience Methods 08/2014; 236. DOI:10.1016/j.jneumeth.2014.08.010 · 2.05 Impact Factor
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    • "Resting state fMRI studies have extensively investigated DMN and have consistently reported abnormal connectivity within the DMN and between the DMN and epileptogenic regions in focal epilepsies (92–98) and IGE (49, 50, 85, 92, 99–102). The most common finding is a decrease in the connectivity within DMN and between the epileptogenic regions with DMN. "
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