Reinforcing Growling with a Reward? - You Can't! By Amy Cook, PhD
"My dog Hansel guards his bed. If I approach his bed and he growls, I shouldn't give him a treat, should I? Wouldn't that be reinforcing the bad behavior?"
No, it actually wouldn't. You can't reward (or punish, either) emotional states and have it work the way it does for other behaviors. Your dog is communicating to you that he is uncomfortable and you should work to convince him to change his mind, giving him less to growl about. If you approach the bed, give him the treat whether he growls or not. Feeding the treat won't be based on his behavior at all. However, it does also help to keep Hansel's discomfort and need to growl at a minimum during this process. If you can approach the bed just close enough where he notices you but hasn't started to growl, start there with tossing the treat and then approach closer as he becomes happy about you being near the bed.
Let's take the reverse of that as an illustration. Say you yell at your dog every time he growls on approaching his bed. What do you think he would learn? That you are pretty bad news when you come over and the growling would most likely increase (along with his other defenses, possibly).
Or lets make it personal. Imagine you feel grumpy at a home-for-the-holidays party, have a headache, and decide to read alone in a bedroom for a while. Your aunt comes in to talk to you, you snap at her that you just want to be left alone, and she lays into you hard for your bad attitude. You might keep it to yourself next time she comes in (maybe, or maybe you'll start screaming at her), but would you stop feeling grumpy? No. You would probably feel worse. You have been "punished" for your behavior, but did it make the feeling behind it go away?
Now say you told her you wanted to be alone and she said "ok, sure, I understand," left, and left behind some chocolate for you. Then an hour later she came back again just to check on you and left a piece of cake from desert. Soon, regardless of how grumpy you were feeling, you might not mind quite so much that she stops by real quick. After all, she leaves great stuff and doesn't bother you. You might even talk to her a little or let her coax you back out to the party (since there is probably more goodies out there).
Are you being rewarded for your snappishness? Do you feel more snappy? Did she "reinforce" your snappy behavior (meaning "make it more likely to happen again")? Probably not.
The bottom line is that dogs learn by association. Teach Hansel to look forward to you coming over and show him through your actions that you are not going to give him anything to worry about, that there is nothing to feel growly about. Don't worry about "rewarding" his behavior. Think about the emotional state underneath.
Want more information? Here's a similar article written by Jess Rollins about growls and rewards.