How does being cross-eyed affect a cat's night-vision?

Question

I recently adopted a kitten who is cross-eyed. She seems to compensate for it pretty well as she is able to jump onto things without problems most of the time, and I think she will get even better over time.

But I was wondering last night, how it might affect her night vision.

I keep the litter boxes in the basement, because it's tile and easier to clean the litter that will kick out of the box while the cats are digging. It hasn't been a problem for my other two cats, I have nightlights plugged into the outlets running from the stairs to the litter boxes so that there's always some light along the way.

Right now I've just left the downstairs light on, because I didn't want her to trip and fall down the stairs trying to make it during the middle of the night. But that's not really something I can do all the time, because I have a chinchilla downstairs that will be bothered by having too much light at night (they're nocturnal).

I was wondering if there was anything to show that cats with cross-eyes see differently in the dark, in case I need to create a better pathway for her.

Answer 1

A Harvard study performed in the 1960s on cats (Hubel and Weisel), which have 3D vision similar to us, included artificially inducing strabismus (cross-eyed). A summary (really, really, basic summary) of the results of the tests indicated a weakening of vision and a loss of depth perception in cats where normal vision was changed in some manner.

While cats can see particularly well in dim light, a reduction in visual acuity and depth perception is only going to get magnified by the absence of stronger light. Having said that, cats can and will compensate for vision issues quite readily, including total blindness, presuming you make it easy for them. If she has a clear path to the litter boxes and knows where they are, she shouldn't have any real issue even when darker. If you left some light, perhaps above and away from the chinchilla (bearing in mind that in the wilderness, light isn't totally absent at night), then it may be sufficient with her own natural skills to keep her in good shape.