The AGF modulates the gain of OTid units in a space-specific manner. (A-C) Effects of aligned AGF stimulation. (A) Red ring: OTid unit whose gain is multiplicatively modified (as shown in inset) by aligned AGF microstimulation. Inset: Visual mnemonic illustrating multiplicative gain modulation of OTid responses by AGF microstimulation. Shown are schematic responses of an OTid unit to a single stimulus inside the RF, without (black) and with (red) microstimulation. X-axis, strength of RF stimulus; y-axis, firing rate. (B) Simulated responses for OTid unit #1 without and with AGF stimulation; AGF→OTid input gain parameter = 0.325, response gain parameter = 1.22; values chosen to show representative results, and correspond to the white ‘x’ in C. (C) Shift in s50 (%; left) and change in transition range (%; right) plotted as a function of input and response gain values (Experimental Procedures). Green arrow: largest magnitude of % change from simulation; red arrow: average % change from experiments.