Successful stereoelectroencephalography-guided radiofrequency thermocoagulation in the treatment of a patient with mesial frontal region-originated mirthful gelastic seizure.

Gelastic seizures (GS), characterized by automatic bouts of unnatural stereotyped laughter and commonly recognized as the hallmark of hypothalamic hamartoma, is rarely associated with cortical epileptogenic focus. Whether there is a dissociation of the motor program of laughter and the experience of mirth and the symptomatogenic zone for ictal laughter with or without mirth are still unclear. We report a patient with drug-resistant mirthful GS who receive a comprehensive investigation of stereoelectroencephalography recording and electrocortical stimulation. Mirthful GS were confirmed to originate from the mesial region of the right superior frontal gyrus, not involving the mesial temporal lobe structures. The patient has been entirely seizure-free after stereoelectroencephalography-guided radiofrequency thermocoagulation. We conclude that the superior frontal gyrus serves as the symptomatogenic zone of ictal laughter and GS with or without mirth share a common neural network.