Figure 8.

Blocking the ON pathway with l-AP4 largely blocks light-evoked responses. Top, Spatial arrangements of the stimuli. A, Average I–V relations obtained at the time-point shown in B. B–D, Average conductances elicited by 1 s light flashes (80%, n = 5. E, Change in the whole-cell zero-current potential. F–J, Same format as A–E, showing the residual response in the presence of 50 μm l-AP4. K–O, Same format as A–E, for the same sample of cells showing responses to light flashes in the subfields adjacent to the center. The stimulus was flashed at two locations 100 and 150 μm above and below the center of the RF. Responses at the two locations were averaged.