Abstracts

Rationale: Ictal EEG recordings (Biraben A, Sartori E, Taussig D Epileptic Disord 1999;1:221-228; Dericioglu N, Cataltepe O, Tezel GG, Saygi S Epileptic Disord 2005;7:1137-141), brain stimulation (Padberg F, Juckel G et al. J Neuropsychiatry Clin Neurosci 2001;13:206-212) and focal brain lesions (Takahashi T, Yucel M et al. Prog Neuropsychopharmacol Biol Neuropsychopharmacol 2010;34:98-103) support the concept of laterality of emotive function. As an epileptic manifestion, laughter most commonly occurs in children who have hypothalamic hamartoma. Among adults, gelastic seizures take origin from other limbic structures, including temporal lobes (Gascon GG and Lombroso CT Epilepsia 1971;12:63-76), cingulate gyrus (Sperli F, Spinelli L, Pollo C, Seeck M Epilepsia 2006;47:440-443), and frontal lobes. Previous citations of gelastic seizures have not suggested a predictable laterality of seizure onset. We performed a review of our patients with gelastic seizures to examine this issue. Methods: We performed a retrospective chart review of adult patients at our institution who reported a gelastic component to their seizure semiologies. We reviewed case histories, brain imaging, interictal EEG, and results of VEEG monitoring. This study was done with the approval of the Institutional Review Board at the Medical University of South Carolina. Results: We identified a cohort of 19 patients who reported gelastic seizures. Fifteen underwent VEEG monitoring which captured their seizures. Three of this group had seizures which arose independently in right and left temporal lobes, the results of which are the subject of this report. These three cases with bilateral seizure onset included 2 women and one man. Data concerning seizure etiology are summarized in Table 1. Twenty-three seizures were recorded among these three patients, including 8 events of right temporal onset, 12 with left temporal onset, and 3 events for which laterality was unclear (Table 2). Half of the seizures with right temporal onset were gelastic, versus none of those of left temporal onset and none of those of indeterminate laterality. Conclusions: Among three patients with complex partial seizures of independent, bilateral temporal lobe onset, gelastic features occurred exclusively with events of right temporal lobe onset. This finding appears to confirm the concept of the cerebral laterality of emotive function.