Color shifts induced by S-cone patterns are mediated by a neural representation driven by multiple cone types.
This study investigated chromatic induction from inhomogeneous background patterns. Previous work showed that a background pattern detected by only S cones induced strong color shifts in a nearby test area (Monnier & Shevell, 2003). In that work, the S-cone patterns were composed with constant L- and M-cone stimulation over the entire background; in terms of L and M cones, therefore, the background was uniform. S-cone stimulation was varied over space to produce S-cone-isolated background patterns. These S-cone patterns, however, established spatial structure (the pattern) at both the receptoral level (S-cone stimulation) and the postreceptoral level (S/(L+M)). Here, these two levels of pattern representation were unconfounded to determine whether color shifts induced by S-cone patterns were due to spatial structure within an S-cone-specific neural pathway versus a pathway that combines responses from S cones and other cone types (e.g. S/(L+M)). The results showed that the induced color shifts were mediated by signals within a pathway that combines responses from multiple cone types. These results are consistent with a +s/-s spatially antagonistic neural receptive field, which is found in some neurons in V1 and V2.
Shevell
Steven K
SK
Department of Psychology and Ophthalmology & Visual Science, University of Chicago, Chicago, Illinois 60637, USA. shevell@uchicago.edu
Monnier
Patrick
P
D003116:Color; D003118:Color Perception / Q000502:physiology*; D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011601:Psychophysics; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology*