Fig. 8.

Bright annular stimuli show that all glycinergic components are elicited from within the dendritic area (center). A: the best annular stimulus to separate center and surround components. The outer diameter of annulus is always 1,000 μm, and the inner diameter is adjusted to encompass the dendrites, and shown below each trace in B–F. The diameters of dendrite of on beta, on parasol, off beta, and off parasol cells are 280, 460, 290, and 320 μm, respectively. Drugs in perfusion are shown above each inset. TS is always in the perfusion to block GABAergic currents and isolate the glycinergic currents. We did not add 2-amino-4-phosphonobutyric acid (APB) in perfusion for on parasol, off beta, and off parasol cells because from Figs. 4–6 we already knew these cells receive only on glycinergic inhibition. Square lines indicate the on (1.5 s) and off of annuli. Currents in E and F are from the same on beta cell.