A Comparison of Cortical Afterdischarge Patterns in the Cat and Rabbit. ∗

Abstract

Summary

Seizures have been elicited by electrical stimulation of the ectosylvian cortex of cats and the cortex acusticus of rabbits with chronically implanted cortical electrodes. The animals were stimulated once only on every other day. Several distinct differences in the cortical afterdischarge and overt seizure patterns were observed between the two species. First, in the cat, an overt seizure always accompanied the bilaterally distributed afterdischarge, while in the rabbit the afterdischarge frequently was elicited in the absence of an overt seizure. Second, in the cat, there was a clear difference between the seizure and the post-seizure periods, both overtly and electrically. Such was not the case in the rabbit. Last, the seizure duration was relatively stable in the cat after a few trials. In contrast, in the rabbit, the duration varied inconsistently from trial to trial.