Cesium has been widely used to study the roles of the hyperpolarization-activated (I(h)) and inwardly rectifying potassium (K(IR)) channels in many neuronal and nonneuronal cell types. Recently, extracellular application of cesium has been shown to produce epileptiform activity in brain slices, but the mechanisms for this are not known. It has been proposed that cesium blocks the K(IR) in glia,...

Medication withdrawal (MW) is an important method of provoking seizures and activating epileptiform EEG activity during the diagnostic work-up of patients evaluated for epilepsy surgery. Previously it was suggested that MW might influence the seizure-type and activate cortical areas otherwise not producing epileptiform discharges, leading to a false localization of the irritative zone. In order...

Excessive synchronous neuronal activity is a defining feature of epileptic activity. We previously characterized the properties of distinct glutamatergic and GABAergic transmission-dependent synchronous epileptiform discharges in mouse hippocampal slices using the 4-aminopyridine model of epilepsy. In the present study, we sought to identify the specific hippocampal neuronal populations that in...

Low-frequency stimulation, delivered through transcranial magnetic or deep-brain electrical procedures, reduces seizures in patients with pharmacoresistant epilepsy. A similar control of ictallike discharges is exerted by low-frequency electrical stimulation in rodent brain slices maintained in vitro during convulsant treatment. By employing field and "sharp" intracellular recordings, we analyz...

Epilepsy, a common neurological disorder, is characterized by the occurrence of spontaneous recurrent epileptiform discharges (SREDs). Acquired epilepsy is associated with long-term neuronal plasticity changes in the hippocampus resulting in the expression of spontaneous recurrent seizures. The purpose of this study is to evaluate and characterize endogenous epileptiform activity in hippocampal...

OBJECTIVES To present long-term outcome and to identify predictors of seizure freedom after vagus nerve stimulation (VNS). METHODS All patients who had undergone VNS implantation in the Epilepsy Centre Bethel were retrospectively reviewed. There were 144 patients who had undergone complete presurgical evaluation, including detailed clinical history, magnetic resonance imaging, and long-term v...

We previously reported that low-frequency electric cortical stimulation (LFECS) directly applied to the epileptic focus by means of subdural electrodes decreased the number of interictal epileptiform discharges in patients with intractable partial epilepsy. In the present study, LFECS was applied to the epileptic foci directly in four patients with medically intractable partial epilepsy through...