Figure 8.

Perceptual consequence of convergent RF shifts. The target is at 0 deg. (A) (Top) RFs of five arbitrary cells before (solid) and after (dashed) the convergence. The “blue” cell tune to the target (0 deg) does not shift. (Bottom) the population responses of all cells to stimulus position x_o = −10 deg before (solid) and after (dashed) the RF convergence. The dashed black and magenta curves are the post-convergence responses plotted against the pre- and post-convergence preferred positions, for the unaware and aware decoders, respectively. (B) Perceptual mislocalization as a function of stimulus position relative to the target (0 deg). The results depend on whether the decoder is aware (magenta) or unaware (black) of the RF convergence, and whether the decoder uses the peak (dashed) or center-of-mass (solid) of population responses. The aware center-of-mass decoder (solid magenta) considers the change of the cells' covering density (see text); it predicts convergent mislocalization as stimuli to the left and right of the target (over a range of about 40 deg) have positive and negative mislocalization, respectively. The aware peak decoder (dashed magenta) predicts no mislocalization. The unaware center-of-mass and peak decoders (solid and dashed black) both predict divergent mislocalization.