Figure 8. Pharmacological characterization of synaptic inputs. A, B, Effect of GABA and glycine antagonists on light-step responses of ON OS RGCs. A, Inhibition, B, Excitation. Yellow rectangle indicates period of light stimulus. C, D, Flashed bar responses of a vertical ON OS RGC in presence of inhibitory blockers. C, Inhibition, D, Excitation. Error bars indicate SEM across five trials at each orientation. E–G, Percentage change in excitatory and inhibitory peak amplitudes in inhibitory antagonists for light step (E), preferred orientation (F), and null orientation (G). Orange and green crosses indicate data from individual ON hOS and ON vOS cells, respectively. H, Effect of inhibitory blockers on OSI of excitatory and inhibitory inputs. Error bars indicate SEM (n = 4 for strychnine, n = 4 for gabazine, and n = 8 for both drugs). Orange and green crosses indicate data from individual ON hOS and ON vOS cells, respectively. ***p < 0.001, *p < 0.05.