Quick Project Snapshot

Functional Connectivity in the Brain

We are investigating changes in functional connectivity of the brain associated with epilepsy. Functional connectivity is a measure of how regions of the brain interact with each other. Brain activation can be mapped non-invasively with functional MRI (fMRI).There are various scales at which one can measure functional connectivity. For example seeded connectivity analysis examines correlations in functional MRI signal between pre-defined regions of interest. This can be extended to the whole brain by examining correlations between all possible pairs of regions throughout the brain. An alternative approach is regional homogeneity analysis, which determines local connectivity (correlations between a voxel and its immediate neighbours). We are also actively developing new methods that can improve the spatial and temporal resolution of functional connectivity measurements.

We have made some important discoveries. For example, we have found that there are common brain areas with abnormal local connectivity in patients with focal epilepsy, despite lesion location varying across individuals. We have also discovered that in some cases a single very small brain lesion can cause widespread change in functional connectivity throughout the brain.

Selected papers

Omidvarnia, A., Pedersen, M., Walz, J.M., Vaughan, D.N., Abbott, D.F., Jackson, G.D., 2016. Dynamic regional phase synchrony (DRePS). Hum. Brain Mapp. 37, 1970–1985. doi:10.1002/hbm.23151

Warren, A.E.L., Abbott, D.F., Vaughan, D.N., Jackson, G.D., Archer, J.S., 2016. Abnormal cognitive network interactions in Lennox-Gastaut syndrome: A potential mechanism of epileptic encephalopathy. Epilepsia 57, 812–822. doi:10.1111/epi.13342

Sethi, M., Pedersen, M., Jackson, G.D., 2016. Polymicrogyric Cortex may Predispose to Seizures via Abnormal Network Topology: An fMRI Connectomics Study. Epilepsia 57, e64–e68. doi:10.1111/epi.13304

Pedersen, M., Omidvarnia, A.H., Walz, J.M., Jackson, G.D., 2015. Increased segregation of brain networks in focal epilepsy: An fMRI graph theory finding. NeuroImage: Clinical 8, 536–542. doi:10.1016/j.nicl.2015.05.009

Pedersen, M., Curwood, E.K., Archer, J.S., Abbott, D.F., Jackson, G.D., 2015. Brain regions with abnormal network properties in severe epilepsy of Lennox-Gastaut phenotype: Multivariate analysis of task-free fMRI. Epilepsia 56, 1767–1773. doi:10.1111/epi.13135

Tailby, C., Masterton, R.A.J., Huang, J.Y., Jackson, G.D., Abbott, D.F., 2015. Resting state functional connectivity changes induced by prior brain state are not network specific. NeuroImage 106, 428–440. doi:10.1016/j.neuroimage.2014.11.037

Pedersen, M., Curwood, E.K., Vaughan, D.N., Omidvarnia, A.H., Jackson, G.D., 2015. Abnormal Brain Areas Common to the Focal Epilepsies: Multivariate Pattern Analysis of fMRI. Brain Connectivity 6, 208–215. doi:10.1089/brain.2015.0367

Masterton, R.A., Carney, P.W., Jackson, G.D., 2012. Cortical and thalamic resting-state functional connectivity is altered in childhood absence epilepsy. Epilepsy Research 99, 327–334. doi:10.1016/j.eplepsyres.2011.12.014

Waites, A.B., Briellmann, R.S., Saling, M.M., Abbott, D.F., Jackson, G.D., 2006. Functional connectivity networks are disrupted in left temporal lobe epilepsy. Annals of Neurology 59, 335–343. doi:10.1002/ana.20733

Waites, A.B., Stanislavsky, A., Abbott, D.F., Jackson, G.D., 2005. Effect of prior cognitive state on resting state networks measured with functional connectivity. Human Brain Mapping 24, 59–68. doi:10.1002/hbm.20069

 

Profile
HEAD OF LAB
Prof Graeme Jackson

Imaging and Epilepsy

The Imaging and Epilepsy group is at the forefront of unravelling the structural and functional abnormalities in the human brain that are associated with epilepsy and other neurological disorders. The group includes several collaborating laboratories, each with multidisciplinary teams of scientists, capable of utilising and advancing cutting-edge neuroimaging technology to address key biological questions in health and disease. Major areas of research include the study of brain networks, connectivity, cognition and injury; neuroimaging analysis methods development / neuroinformatics; and clinical translation to improved patient care.

All Projects by this Lab

Epilepsy Neuroinformatics LaboratoryEpilepsy Cognition LaboratoryPsychology and Experimental NeurophysiologyTraumatic Brain Injury LaboratoryFunctional Connectivity in the BrainClinical Translation

Epilepsy

The Florey's Epilepsy division is a world-leading centre for epilepsy research. The division has major groups at both the Florey’s Austin and Parkville campus. The group studies mechanisms that cause epilepsy from the level of cells to the function of the whole brain. We use technologies including advanced MRI and cutting edge cellular physiology techniques to allow us to understand genetic and acquired mechanisms that give rise to epilepsy. Together with our colleagues from The University of Melbourne and across Australia we are working towards finding a cure for epilepsy.

All Labs that operate in this Division

Epilepsy Cognition LaboratoryEpilepsy Neuroinformatics LaboratoryImaging and EpilepsyInnate Phagocytosis LaboratoryIon Channels and Human Diseases LaboratoryNeural Networks LaboratoryNeurophysiology of Excitable Networks LaboratoryPsychology and Experimental NeurophysiologySleep and CognitionTraumatic Brain Injury Laboratory