A dog’s brain and your brain have very similar chemistry and many similar structures. It stands to reason they work in more or less the same way—and break down the same way too. More and more, behavioral veterinarians are diagnosing problems as diverse as depression, anger, dementia and post-traumatic stress disorder in dogs. As with humans, treatment involves behavioral therapy and sometimes even drugs. But first you have to know if a problem exists at all. Here are some of the symptoms veterinarians consider in making a diagnosis.