Ever move your couch, only to watch your dog run into it? Owners of canine senior citizens sometimes think their dog has suddenly gone blind, when a gradual visual loss is far more common.

Dogs are good at memorizing their surroundings, so gradual blindness doesn’t show up until new obstacles are introduced, such as when the furniture is rearranged.

Here are some ways to see if vision problems have dimmed your old dog’s view. Drop a light cloth to see if your dog follows it as it drifts to the ground. Next, watch how your dog navigates an unfamiliar room in dim light. Dogs normally have great night vision, so bumping into things means that some sight is lost.

There’s no need to panic if your best friend can’t see well … or even at all. With the help of their other senses, old pups do fine. They don’t need to read the box score, just sniff out you and the food bowl.