[2 types of lateral inhibition in frog retinas].

The influence of different pharmacological agents on the inhibition in the frog retina was investigated by means of recording ERG from the inner plexiform layer. Two different types of lateral inhibition were distinguished: "near", sensitive to picrotoxin, and "distant", sensitive-strychnine. The "distant" inhibition appears to be the familiar lateral inhibition transmitted by propagating spikes. The "near" picrotoxin-sensitive lateral inhibition does not depend on propagating spikes. Localization of two types of lateral inhibition in the plexiform layers is discussed.