When cats get sick, they can’t tell you where it hurts or when the pain started. However if you’re observant, you might be able to decipher any pain in your cat by examining its face.

Scientists have determined that animals display pain through facial expressions called a grimace scale. Grimace scales include a series of images that show how facial expressions change when animals experience no, moderate and severe pain.

So the next time your cat glares at you, it could be in pain or it could be disgusted by your behavior. Whatever the case, your cat’s face can tell you how it may be feeling.

To learn more about studying your cat’s expression to detect pain, click here.