Abstract
Temporarily depriving one eye of its input, in whole or in part, may result in transient changes in ocular dominance and contrast detection thresholds, with the patched eye becoming stronger and more sensitive and the unpatched eye weaker and less sensitive. Here we address two distinct questions about the role of color vision in these plastic changes. First, we ask whether the target effects of eye deprivation are selective or broadband, for example, whether changes in ocular dominance differentially affect stimuli defined by achromatic as opposed to color contrast. Second, we determine the selectivity of the process driving the inter-ocular plastic changes, asking whether chromatic contrast, in comparison to achromatic contrast, is effective in changing ocular dominance. In experiments 1 and 2, we compare the effects of generalized deprivation on chromatic and achromatic test stimuli, using a translucent occluder over one eye for 2.5-hours. This produced changes in ocular dominance, measured using a dichoptic phase combination paradigm (Zhou et al., 2013, J. Vision, 13(12)), and changes in contrast thresholds that are similar in magnitude and time course for chromatic and achromatic test stimuli. In experiments 3 and 4, we use a dichoptic movie-viewing paradigm (Zhou et al., 2014, Proc. Biol. Sci., 281) to investigate the role of color versus achromatic contrast in driving these effects. We show that a color contrast imbalance between the eyes (uni-ocular chromatic deprivation) is not sufficient to produce changes in ocular dominance for chromatic test stimuli. However, an achromatic imbalance with no chromatic imbalance (uni-ocular achromatic deprivation) causes a generalized change in ocular dominance that affects both chromatic and achromatic test stimuli similarly. We conclude that an interocular imbalance in achromatic contrast, and not chromatic contrast, drives plastic changes in ocular dominance, however, these changes apply unselectively to both chromatic and achromatic responses.
Meeting abstract presented at VSS 2016