The parahippocampal cortex (PHC) is the gate region to the hippocampal formation, critically involved in memory and learning functions. Intrinsic and extrinsic connectivities of the PHC have been extensively analyzed. A new picture is emerging according to which longitudinal bands of PRC and EC are efficiently interconnected, whereas the propagation of activity between PHC subregions is under an inhibitory control that regulates the flow of information to the hippocampus (de Curtis and Paré, Prog Neurobiol, 74, 2004: 101–10). A breakdown of inhibition that characterizes the interactions within PHC may initiate hyperexcitability phenomena that promote ictogenesis. Findings obtained on an acute model of ictogenesis established that network changes of PHR excitability occur during repetitive episodes of seizures in the EC-hippocampus of the isolated guinea pig brain preparation. Seizures induced by acute treatment with bicuculline generate ictal discharges that initiate most frequently in the medial EC and rapidly propagate to the hippocampal formation. The PRC could be entrained exclusively when seizures are repeated. These findings suggest that the priming effect mediated by seizure activity modifies network interactions within PHC and enhance PHC excitability. The role of such dynamic changes during the interictal-to-ictal transition in sustaining temporal lobe epileptogenesis will be discussed.