With epileptic activity, neurons show paroxysmal depolarization shifts (PDSs) corresponding to epileptic field potentials (EFPs) generated by the neuronal population. Experimental results indicate that calcium and calcium-dependent currents participate in the generation of these events. Consequently neuronal PDS/EFP were depressed by organic calcium channel blockers. This justifies the hope that calcium channel blockers might be useful in the treatment of human epilepsies.