Low Frequency (<<100Hz) applied electric fields have been shown to modulate neuronal activity both In Vitro and in acute whole animal studies. We have been working to apply this technology for seizure control in chronically implanted animals. We have developed electronics for simultaneously recording neural activity while stimulating with low frequency fields. We have observed transient entrainment of spike and wave activity during spontaneous seizures with open loop sinusoidal stimulation with frequencies between 9-15 Hz. This is the first demonstration of low frequency field modulation of neural activity in chronically implanted mammalian brain.