title: Resting state functional network disruptions in a kainic acid model of temporal lobe epilepsy.
abstract: We studied the graph topological properties of brain networks derived from resting-state functional magnetic resonance imaging in a kainic acid induced model of temporal lobe epilepsy (TLE) in rats. Functional connectivity was determined by temporal correlation of the resting-state Blood Oxygen Level Dependent (BOLD) signals between two brain regions during 1.5% and 2% isoflurane, and analyzed as networks in epileptic and control rats. Graph theoretical analysis revealed a significant increase in functional connectivity between brain areas in epileptic than control rats, and the connected brain areas could be categorized as a limbic network and a default mode network (DMN). The limbic network includes the hippocampus, amygdala, piriform cortex, nucleus accumbens, and mediodorsal thalamus, whereas DMN involves the medial prefrontal cortex, anterior and posterior cingulate cortex, auditory and temporal association cortex, and posterior parietal cortex. The TLE model manifested a higher clustering coefficient, increased global and local efficiency, and increased small-worldness as compared to controls, despite having a similar characteristic path length. These results suggest extensive disruptions in the functional brain networks, which may be the basis of altered cognitive, emotional and psychiatric symptoms in TLE.
authors.affiliation: Graduate Program in Neuroscience, Western University, London, Ontario, Canada; Department of Physiology & Pharmacology, Western University, London, Ontario, Canada.
authors.forename: Ravnoor Singh
authors.initials: RS
authors.lastname: Gill
authors.affiliation: Graduate Program in Neuroscience, Western University, London, Ontario, Canada; Clinical Neurological Sciences, Western University, London, Ontario, Canada; Department of Biomedical Imaging, Western University, London, Ontario, Canada; Department of Biomedical Physics, Western University, London, Ontario, Canada; Department of Psychology, Western University, London, Ontario, Canada.
authors.forename: Seyed M
authors.initials: SM
authors.lastname: Mirsattari
authors.affiliation: Graduate Program in Neuroscience, Western University, London, Ontario, Canada; Department of Physiology & Pharmacology, Western University, London, Ontario, Canada.
authors.forename: L Stan
authors.initials: LS
authors.lastname: Leung
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology*; D063132:Connectome / Q000379:methods*; D004195:Disease Models, Animal; D004833:Epilepsy, Temporal Lobe / Q000139:chemically induced / Q000000981:diagnostic imaging / Q000503:physiopathology*; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D007608:Kainic Acid / Q000494:pharmacology; D008032:Limbic System / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000503:physiopathology*; D051381:Rats; D020318:Rats, Long-Evans
chemical_list: D018690:Excitatory Amino Acid Agonists; D007608:Kainic Acid
keywords: Default mode network; Functional connectivity; Kainic acid; Limbic system; Resting-state networks; Temporal lobe epilepsy