SPATIAL RECONSTRUCTION OF SIGNALS FROM SHORT-WAVELENGTH CONES

Because the retinal cone mosaic samples an image only at discrete locations, our continuous visual percept must arise from a spatial reconstruction process. How this process combines information from the three cone types is presently unclear. To investigate, we asked whether L and M cone information can modify the visual system's reconstruction of signals from S cones. In Expt 1, we used a matching paradigm to measure the effect of L and M cone information on filling-in at the foveal tritanopic area. We found that a small luminance disk superimposed at the tritanopic area decreases the amount of filling-in, showing that the reconstruction of S cone signals can be influenced by the spatial pattern seen by the L and M cones. In Expt 2, we asked whether L and M cone information can modify the splotchy low-frequency alias seen when an observer views fine S cone gratings. Here there was no evidence for an interaction. We conclude that though L and M cone information can influence the visual system's reconstruction of S cone signals, this influence may be confined to relatively coarse spatial patterns.