Degeneration in Experimental Epileptic Foci

Alumina cream sensorimotor cortical lesions inMacaca mulattaare investigated acutely (one day to two months) and after becoming epileptic at intermediate (three to six months) and chronic (1¾ to 51/2 years) stages. Development of foci is studied with electroencephalograms and precise localization accomplished by transdural electrocorticography. Nissl stains and reduced silver methods of Nauta-Gygax and Fink-Heimer are used for histologic changes. Degeneration from acute lesions coincides with described connections and is compared to degeneration at intermediate and chronic stages. Chronic epileptic animals show degeneration in sensorimotor cortex, secondary motor cortex, and centrum white matter. Myelogenic bands of Baillarger contain most cortical degenerating fibers and terminals which may be more retrograde than the wallerian type. Lack of Nissl substance loss prevents cell-of-origin identification. Chronic animal degeneration documents continued deterioration in the brain from this type of elipepsy.