Language-apparent reflex epilepsy.
An adolescent with photosensitive epilepsy had absence seizures reproduced by forced voluntary eye closure in light or in darkness, independent of eyelid immobilization or ocular elevation. Attacks preferably occurred while speaking Spanish, her second language, mediated through brief, strong, automatic closing of the eyes during difficult word retrieval. Complex other multidirectional ocular movements or blinking, cognitive and language tasks were ineffective. Frontorolandic cortical epileptogenesis is seemingly responsible for light-provoked seizures in Papio papio, acting via hyperexcitable neuronal facial aggregates (i.e. Baba and Wada). Since orbicularis oculi muscle fibers mediating strong and weak contractions are differentially innervated by the facial nuclei, we submit that critical threshold tonic activation of specific nuclear aggregates explains this language-apparent reflex epilepsy, triggered by extreme eye closure. A "dopamine connection hypothesis" linking periodic eye closure, effortful memory and photosensitivity, based on its putative evolutive significance, is discussed.
Jacome
D E
DE
Department of Medicine, Palmetto General Hospital, Hialeah, Florida.
D000293:Adolescent; D004569:Electroencephalography; D004832:Epilepsy, Absence / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007802:Language; D008027:Light; D012018:Reflex