The predicted response is where r(t) is the response at time t to a bar at position x and temporal frequency w, and f is the spatial frequency of the simulated grating.

Figure 4 shows the original 2Hz control histograms in red, and the same histograms after shifting them by xf/w in diagonally-hatched colors. Figure 5 then shows the sum of these shifted histograms by stacking them on top of each other, as well as the sum shown by a black line. The sum is actually computed more continuously than the stacked histograms, which are shifted by an integral number of bins, so that the black line is smoother.

Figure 4

Figure 5

This process was applied to both the control and adapted responses, and figure 6 shows the results (the sum shown above is divided by the number of positions tested, 8). **The stationary maps suffice to predict the timing aftereffects seen with drifting gratings.** Thus, the timing aftereffects seen with moving stimuli do not depend on some dynamic, nonlinear process, but instead arise from receptive field structure.

Figure 6

Next section is Effects of Adapting on Localized Responses.

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