Figure 5. Seizures beget seizures in the immature hippocampus. A: A triple chamber is used (top left) with three compartments that accommodate each intact hippocampus and the connecting commissural connections. B: When the powerful convulsive agent kainate is applied, epileptiform activities are generated in the treated side and propagate rapidly to the naive side (top left). C: After repeated applications and seizure propagation to the naive side, tetrodoxin (TTX) a blocker of action potentials and of the propagation of seizures, was applied to the commissural chamber and effectively blocked seizures. Note (bottom part) that seizures were generated spontaneously by the naive hippocampus after disconnection form the treated side: there is formation of an epileptogenic mirror focus.⁷⁶ .