Generation of High Frequency Oscillations (80–500Hz) in different anatomical structures and their relation to the seizure onset zone

Introduction: High frequency oscillations (HFOs) known as ripples (80–250Hz) and fast ripples (250–500Hz) can be recorded from macroelectrodes inserted in patients with intractable focal epilepsy. Although ripples may occur physiologically in the hippocampus, both events are also most likely linked to epileptogenesis and have been found in the seizure onset zone (SOZ) of human ictal and interictal recordings. HFOs have been mainly described in the mesial temporal structures (MTS), but they were also found in neocortical areas (NC). We investigated the variability of HFOs in different anatomical structures and wh…