To support my answer above, here is a quote from a scientific paper: "polarization sensitivity has long been associated with behavioral tasks like orientation or navigation. However, only recently have we become aware that it can be incorporated into a high-level visual perception akin to color vision, permitting segmentation of a viewed scene into regions that differ in their polarization. By analogy to color vision, we call this capacity polarization vision. It is apparently used for tasks like those that color vision specializes in: contrast enhancement, camouflage breaking, object recognition, and signal detection and discrimination (Cronin et al., 2003, Integr. Comp. Biol. (2003) 43 (4): 549-558. doi: 10.1093/icb/43.4.549 ). Therefore by artificially subjecting our eyes to fully linearly polarized light, such as what we see through polarized sunglasses, we somehow "trick" our photoreceptors into seeing certain signals in nature that are not acutally present. Note that the paper also mention that some organisms are more sensitive to polarization and some are not. So this could be akin to other people getting dizzy with polarized shades and some not.