Background/Aim: This study aimed to compare the cortical excitability of patients with generalized tonic-clonic seizures (GTCSs) and that of patients with psychogenic non-epileptic seizures (PNESs). Methods: Patients were classified into groups according to their electroencephalogram (EEG) findings and seizure types: group 1 = GTCS with an abnormal EEG, group 2 = GTCS with a normal EEG and group 3 = PNES with a normal EEG. The control group included healthy volunteers with normal EEGs. Cortical silent period (CSP) and motor threshold (MT) were measured for all groups and the results were compared. Results: CSPs were significantly prolonged in groups 1 and 2 when compared with group 3 and the control group. No differences were found between the MT measurements of all groups. Conclusion: The prolongation of CSP may demonstrate the differences between the pathophysiological mechanisms of GTCS and those of PNES.

Keywords:
Transcranial magnetic stimulation, Motor threshold, Cortical silent period, Epilepsy, Psychogenic non-epileptic seizure
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2012
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