Abstract
Ocular dominance is a basic visual property that shows short-term plasticity in adult humans, where 2h of monocular deprivation leads to a homeostatic shift of ocular dominance in favour of the deprived eye. Using an altered reality setting, we found that this homeostatic plasticity can be triggered without depriving one eye of visual input, but merely perturbing the temporal correspondence between voluntary actions and vision in one eye. Participants wore a VR set; its monocular screens were connected with cameras monitoring the front space, which participants used to perform a complex visuomotor task. During a 60 minute period, the input to the dominant eye was delayed by 333 ms, making it useless for visuomotor coordination. Following this, ocular dominance (quantified by binocular rivalry) was systematically shifted in favour of the delayed eye, a similar effect as that produced by monocular contrast-deprivation. The shift was only observed when participants actively engaged in the visuomotor task, not when they passively watched a confederate perform the same task. We interpret these results in the light of parallel fMRI experiments where monocular deprivation is associated with a global system reconfiguration that pivots around a key area for sensorimotor integration, the Pulvinar. Based on our findings, we suggest that active vision is foundational to weighting sensory information, even at the level of simple visual processes as those setting ocular dominance.
Funding: Funding: This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme, grant n. 801715 (PUPILTRAITS) and n. 832813 (GenPercept) and by the Italian Ministry of University and Research under the PRIN2017 programme (grant MISMATCH and 2017SBCPZY) and FARE-2 (grant SMILY).