It turns out that your dog's brain isn't all that different from your own. Dr. Nicholas Dodman, director of the behavior clinic at Tufts Cummings School of Veterinary Medicine, North Grafton, MA, has been studying compulsive behaviors in dogs, horses and cats for decades. And for years he's been encouraging using these animal models to help understand what's going on with people with obsessive-compulsive disorders (OCD). However, he's had to wait for both popular scientific culture and gene identifying scientific techniques to catch up with his notions.