. >> reporter: researcher and writer laurel braitman, author of "animal madness," says our pets have deeper emotional lives than most of us give them credit for. what sort of emotional complexity is there for a dog? i mean, we like to think that the dog is wagging his tail because he's happy to see you when you come home when part of you suspects, maybe it's just because he's hungry. >> we're like that, too. are we happy when we sit down in a restaurant because we're about good friends? it's safe to say that other animals particularly dogs can be happy and sad and anxious and fearful. >> we're going to present him with our closed fist with a treat. >> reporter: across town, hachi is meeting with trainer erica. >> he's like, oh, that's what you were looking for. >> reporter: the prozac gives him that extra help to succeed, according to his owner. >> you still have to do the behavior modification and be extremely diligent and dedicated because the prozac is not going to solve the problem. >> you'll see, he's just howling. >> reporter: morgan and jason show hachi in a full-blown panic a

. >> reporter: researcher and writer laurel braitman, author of "animal madness," says our than most of us give them credit for. >> what sort of emotional complexity is there for a dog? we like to think that the dog is wagging his tail because he's happy to see you when he come home but part of you suspects maybe it's just because he's >> we're like that, too. are we happy when we sit down in a restaurant because we're with good friends or about to eat? it's safe to say that other animals particularly dogs can be happy and sad and anxious and fearful. >> we're going to present him with our closed fist with a treat. >> across town, hachi is meeting with trainer erica. >> he's like, oh, that's what you were looking for. >> the prozac gives him that extra help to succeed, according to his owners. >> you still have to do the behavior modification and be extremely diligent and dedicated because the prozac is not going to solve the problem. >> morgan and jason show us hachi in a full-blown panic attack. he's been alone for five hours. >> he's pacing. now he's whining. so he's clearly stres