EEG source imaging and connectivity analysis in epilepsy patients

EEG represents a useful tool to study the electrophysiological brain activity. EEG has also been widely used to help diagnose the epilepsy and study the underlying brain sources of epileptic activity. Here, we present a study of imaging the seizure activity of epilepsy patient from noninvasive scalp EEG. A spatio-temporal EEG source localization approach (FINE) was firstly applied to localize the active sources during ictal period. Connectivity analysis of directed transfer function (DTF) was then utilized to identify the primary source of seizure onset. Computer simulation was performed to study the source localization in dipolar sources. The method was applied in a medically intractable epilepsy patient to localize the seizure onset zone. The effect of electrode numbers in source imaging results was also investigated in the computer simulation.