Figure 3. Orientation tunings of output responses with and without inhibition.
(A) Superimposed normalized excitatory (red) and inhibitory (blue) conductances evoked by bars of preferred and orthogonal orientations in the example cell shown in Figure 2 (marked by arrows). Inset, average conductance waveforms of all the recorded cells. Before averaging traces were aligned according to the onsets of excitatory responses.
(B) Left, normalized orientation tuning curves of the same cell’s PSP responses derived from excitatory inputs alone (red), derived by integrating excitatory and inhibitory inputs (magenta), and experimentally recorded (black). Right, actual tuning curves of derived PSP responses. “a” and “b” with arrows mark the reduction of PSP response at preferred and orthogonal orientations, respectively.
(C) OSIs of excitatory conductance (Ex), recorded Vm response (Vm), simulated Vm response with the excitatory input alone (Vmsimu(E)) and simulated Vm responses with integrating excitatory and inhibitory inputs (Vmsimu(E+I)). Solid symbol = mean ± SD. *, p < 0.01, ANOVA with post hoc test, n = 12.
(D) Average normalized PSP tuning curves. Bar = SE, n = 12.
(E) Reduction of PSP response at preferred and orthogonal orientations. Solid symbol = mean ± SD. *, p < 0.01, paired t-test.
(F) OSIs of spike response (OSIAP) for spikes recorded, spikes simulated by integrating excitatory and inhibitory inputs (Simu(E+I)), and those simulated with the excitatory input alone (Simu(E)). Solid symbol = mean ± SD. *, p < 0.001, ANOVA with post hoc test.