Synchronized retinal oscillations encode essential information for escape behavior in frogs

Synchronized oscillatory activity is generated among visual neurons in a manner that depends on certain key features of visual stimulation. Although this activity may be important for perceptual integration, its functional significance has yet to be explained. Here we find a very strong correlation between synchronized oscillatory activity in a class of frog retinal ganglion cells (dimming detectors) and a well-known escape response, as shown by behavioral tests and multi-electrode recordings from isolated retinas. Escape behavior elicited by an expanding dark spot was suppressed and potentiated by intraocular injection of GABA(A) receptor and GABA(C) receptor antagonists, respectively. Changes in escape behavior correlated with antagonist-evoked changes in synchronized oscillatory activity but not with changes in the discharge rate of dimming detectors. These antagonists did not affect the expanding dark spot-induced responses in retinal ganglion cells other than dimming detectors. Thus, synchronized oscillations in the retina are likely to encode escape-related information in frogs.