Fig. 2.

The pre-processing steps used to standardize each cone’s reflectance. Raw cone reflectance signals were extracted from each included cone for the control (A, 569 cones) and stimulated (D, 675 cones) image sequences. For visualization here, we display each cone’s reflectance signal relative to its starting value. To remove the effect of frame-to-frame changes in image intensity, each cone’s reflectance was scaled by the mean cone reflectance at each time point for the control (B) and stimulated image sequences (E). As in (A) and (D), each cone’s reflectance signal is relative to its starting value for visualization only. (C, F) Finally, individual cone reflectance signals were standardized to their pre-stimulus behavior by subtracting each cone’s pre-stimulus mean from itself, then dividing by its pre-stimulus standard deviation. Stimulus duration indicated by the black bars.