We demonstrated in humans the involvement of the centromedian and parafascicular part of the corticoreticular system and of the anterior nucleus part of the limbic system during generalized spike-and-wave discharges. The different time courses suggest that the posterior intralaminar nuclei may be involved in epileptic discharge initiation or early propagation, while the anterior nucleus may only play a role in its maintenance. These results may help to understand the clinical effect of deep brain stimulation within thalamic nuclei in intractable idiopathic generalized epilepsy patients.

These findings might be helpful in epilepsy surgery candidates, to better target investigation of the CMA, pre-SMA, and SMAp, and therefore to provide a better understanding of premotor seizures.

No abstract

Summary:Purpose: Substantial data are missing about the anatomic location of frontal regions supporting gelastic seizures.Methods: We report the results of stereo-electro-encephalographic recordings performed over several distinct functional premotor and executive fields in a patient whose seizures were characterized by dyskinetic behavior and ictal laughter, in the absence of cerebral MRI abnormalities.Results: The epileptogenic zone was circumscribed in the anterior and ventral part of the supplementary motor area and the underlying dorsal cingulate cortex. There were no or little spreading to cortical neighboring areas. The patient is seizure-free (follow-up of 27 months) after a stereotactic electric radiofrequency lesion of the epileptogenic focus.Conclusion: The present data suggest that pericingulate premotor areas are involved in the triggering of the motor component of laughter. In this case, the coexistence of paroxysmal dyskinesias during laughter might reflect the involvement of specific compartment(s) of the basal ganglia. Key words: Brain mapping-cingulate gyrus-cingulate motor areas-dyskinesia-electric stimulation-frontal lobe epilepsy-human-laughter-magnetic resonance imagingradiofrequency lesion-stereo-electro-encephalography-supplementary motor area.