For the most part cats aren't expressive. Yes, they communicate with whiskers, ears, eyes, and tail postures, but not like dogs. A recent study shows that dogs actually study our expressions and mimic them in an attempt to communicate with us. On the other hand, cats are wired to hide their emotions. Because they are solitary creatures by nature, they don't require facial expressions to communicate with one another. And in the wild if they express fear or pain, they become vulnerable to preditors and other cats looking to take over their territory and resources. This makes it very difficult to know if your cat is feeling stress or pain and makes their unwanted behaviors particularly difficult to decipher.