Pathological high-frequency oscillations are a novel marker used to improve the delineation of epileptogenic tissue and, hence, the outcome of epilepsy surgery. Their practical clinical utilization is curtailed by the inability to discriminate them from physiological oscillations due to frequency overlap. Although it is well documented that pathological HFOs are suppressed by antiepileptic drugs (AEDs), the effect of AEDs on normal HFOs is not well known. In this experimental study, we have explored whether physiological HFOs (sharp-wave ripples) of hippocampal origin respond to AED treatment. The results show that application of a single dose of levetiracetam or lacosamide does not reduce the rate of sharp-wave ripples. In addition, it seems that these new generation drugs do not negatively affect the cellular and network mechanisms involved in sharp-wave ripple generation, which may provide a plausible explanation for the absence of significant negative effects on cognitive functions of these drugs, particularly on memory.

Department of Circuit Theory Faculty of Electrical Engineering Czech Technical University Prague Prague Czechia

Department of Developmental Epileptology Institute of Physiology The Czech Academy of Sciences Prague Czechia

Department of Neurology 2nd Faculty of Medicine Charles University and Motol University Hospital Prague Czechia

Department of Neurology Samsung Medical Center Samsung Advanced Institute for Health Sciences and Technology Sungkyunkwan University School of Medicine Seoul South Korea

Department of Neurology Thomas Jefferson University Philadelphia PA United States

Samsung Biomedical Research Institute Seoul South Korea

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Epilepsy Research in the Institute of Physiology of the Czech Academy of Sciences in Prague

How do we use in vitro models to understand epileptiform and ictal activity? A report of the TASK1-WG4 group of the ILAE/AES Joint Translational Task Force