PURPOSE OF REVIEW: Tremendous advances have occurred in recent years in 
elucidating basic mechanisms of epilepsy at the level of ion channels and 
neurotransmitters. Epilepsy, however, is ultimately a disease of functionally 
and/or structurally aberrant connections between neurons and groups of neurons 
at the systems level. Recent advances in neuroimaging and electrophysiology now 
make it possible to investigate structural and functional connectivity of the 
entire brain, and these techniques are currently being used to investigate 
diseases that manifest as global disturbances of brain function. Epilepsy is 
such a disease, and our understanding of the mechanisms underlying the 
development of epilepsy and the generation of epileptic seizures will 
undoubtedly benefit from research utilizing these connectomic approaches.
RECENT FINDINGS: MRI using diffusion tensor imaging provides structural 
information, whereas functional MRI and electroencephalography provide 
functional information about connectivity at the whole brain level. 
Optogenetics, tracers, electrophysiological approaches, and calcium imaging 
provide connectivity information at the level of local circuits. These 
approaches are revealing important neuronal network disturbances underlying 
epileptic abnormalities.
SUMMARY: An understanding of the fundamental mechanisms underlying the 
development of epilepsy and the generation of epileptic seizures will require 
delineation of the aberrant functional and structural connections of the whole 
brain. The field of connectomics now provides approaches to accomplish this.