Electrical stimulation can inhibit synchronized neuronal activity.

The effect of electrical stimulation on abnormal neuronal activity was studied in the hippocampus in vitro. Epileptiform electrical activity was induced by adding penicillin or picrotoxin to the perfusing medium. Orthodromic stimulation generated large repetitive field potentials measured extracellularly. Electrical stimulation was then applied to the neurons with a 50 micron electrode located in the somatic layer. Large decreases in the amplitude of the population spikes were generated when stimulation was synchronized with the electrical activity. The inhibitory effect was charge-dependent and could be obtained with applied electrical charges similar to those used to stimulate nerves in the central nervous system. It is suggested that this method could be useful to prevent the synchronization and propagation of epileptic seizures.