Most people reward anxious behaviors by trying to comfort the dog. I find it's best to ignore any signs of stress. That's how I do it. I sit quietly at the vet, my dog sits quietly, while dogs around us are yelping, jumping, and owners are saying stuff like your good boy, and rewarding that excited behaviors
We practice being calm here. It's one main technique I learned from Cesar Milan. Calm the mind, calm the body.
Yes. This is similar to the person who was talking about the uncomfortable person walking through the city and the dog picking up on it. Dog's also pick up on your calm. My husband wants to yell at the dog when she barks, I think it's counter productive. I try and be calm and the dog is calmer. I don't get worked up and the dog doesn't get worked up. With strangers we just tell them to ignore the dog, and it works like a charm and she wants to be buddies within moments, but if they engage her when she is riled up then she get's more excited (not always in good ways). My dog has anxiety in the car. The better I am at totally ignoring her and driving like she's not even in the car, the better off we do.