Abstract
It is known that short-term monocular deprivation (MD) via patching enhances the deprived eye’s dominance in binocular rivalry. Recently, we reported that scrambling the phase without changing the amplitude spectra of images input to one eye induced a similar shift of perceptual eye dominance. An interesting question is whether the increase in eye dominance also applies during perception of natural scene stimuli without conspicuous interocular competition. Moreover, to our knowledge, all the past work on short-term MD has focused on testing the eye dominance before and after the MD. It thereby remains largely unknown whether and how the eye dominance changes during the MD. Here we used the steady-state visual evoked potential (SSVEP) technique to measure the neural effects of MD with natural scene tests. Images to the two eyes were tagged with different frequencies. Two kinds of tests were used. One was an unfiltered test with both eyes receiving the original video images. The other was a MD test with an intact image presented to the non-deprived eye and mean luminance or pink noise presented to the deprived eye. The unfiltered test was conducted before and after 120 min of MD, and the four MD tests was conducted at 4 points during the deprivation. The results from the unfiltered tests showed that 120 min of MD boosted the SSVEP amplitudes elicited by the inputs from the deprived eye relative to the non-deprived eye (occipital electrodes, t(19) > 3.08, p < 0.01), indicating increased neural gain for the deprived eye. However, for the MD test during deprivation, the ratio of SSVEP amplitudes for the deprived vs. non-deprived eye did not change significantly over time; this puzzling result requires further exploration. Our findings suggest that the effects of short-term MD can be evident with natural scene stimulation without strong interocular competition.