Penicillin-induced epileptiform activity does not prevent ocular dominance shifts in monocularly deprived kittens

Epileptiform activity was induced in the visual cortex with penicillin to test whether it would prevent the ocular dominance shift that normally occurs in monocularly deprived kittens. The eyelids of one eye of 5-week-old kittens were sutured shut for several days. During this period, whenever the kittens were in the light, aqueous penicillin in artificial cerebrospinal fluid (CSF) or just CSF was applied in a cylinder mounted over the visual cortex. Electroencephalograms monitored during the period of deprivation indicated nearly continuous interictal spiking in the visual cortex. Extracellular recordings were made of cells in the region directly under the position of the cylinder. 14C-labeled 2-deoxyglucose autoradiography in a control kitten showed that this area had considerably increased metabolism during epileptiform activity. The majority of cortical cells were dominated by the non-deprived eye in both epileptic and control kittens, with no noticeable difference between them. These preliminary observations indicate that the disruption of cortical activity that occurs during interictal epileptiform activity does not prevent the ocular dominance shift in monocularly deprived kittens.