Fig. 6.

Orientation specificity of the effect of conditioning. (a) 2D representation of conditioning orientations. (Upper) Definition of θ₁ and θ_2. S₁ and S₂ represent the first and second gratings in the conditioning pair; curve represents tuning of the cell. (Lower) Each dot represents a combination of θ₁ and θ₂ used in experiments. Small outer plots depict stimulus configurations for selected points (indicated by arrows). (b) Conditioning-induced shift in tuning as a function of θ₁ and θ₂ predicted by the model. Magnitude of shift is represented by luminance (scale, Right). Diagonal line, θ₁ = θ₂, conditioning in which both gratings are at the same orientation. (c) Measured shifts in V1 orientation tuning at [θ₁, θ₂] indicated by dots in a (n = 14-74 per point). Arrowheads, data points significantly different from 0 (P < 0.03, Wilcoxon signed rank test). (d) Contour plot of the results shown in c.