Has your brain ever just fallen out of your head?
It happens to me every once in a while. For instance, last week at work, they were "updating" our computers. If you're lucky enough not to require computers for your job, you might not realize that "update" is actually tech-speck for "now your computer will not do any of the things you really, really, really need to do, nyah nyah nyahnyah nyah." How do I react when my computer doesn't work? I start pressing buttons harder. I hit it a few times. I swear. A lot. Because I am convinced on some level that if I can find the right combination of violence and cursing, my computer will be intimidated into working the way I intend it to (the stupid piece of *^&%&*).
This is called an "extinction burst."
The phenomena is actually one of those handy evolutionary survival techniques. When what we do doesn't work anymore, we try harder. Pretend you're a lion in Africa. You're chasing a gazelle and you're running really fast but dang it, the little bugger gets away. What do you do? Do you curl up and starve? Do you attempt a previously untried new strategy for catching gazelle? Most likely, you try chasing it again, only you try harder next time. And, y'know, maybe swear a little.
Or a lot (really, what do I know about lions?).
Speaking of swearing, extinction bursts can be a real hit to the ego if you happen to have a five year old reactive pit bull. You're cruising along thinking, hey, we're not doing so bad - in fact, I might classify this as "good" when WHAM! Psycho dog re-emerges and you get left holding the leash wondering why you suddenly suck as a trainer.
I have one advantage and one advantage only over most of the people I teach: experience. I'm not a guru of dog behavior, nor do I have some special gift. I had to learn this stuff from the ground up, too. In my experience, the best way to combat an extinction burst is with consistency. Keep doing what you're doing. Eventually this, too, shall pass. Many people give up when the behavior suddenly worsens. The dog who whines at the dinner table is ignored - right up until he starts barking at the dinner table. Then he gets attention to shut him up. Now, when he realizes whining isn't working for him anymore, he'll go to bark faster because, hey, it worked last time. On the other hand, if you ignore the dog when he starts barking, eventually he'll stop and realize that making noise isn't working for him anymore.
Extinction bursts are the oncoming train at the end of the tunnel. Once the train passes, the light of day is clear. Metaphor aside, extinction bursts mean the the dog is about to realize the previously rewarding behavior isn't working anymore. If she barks at other dogs, she's still not going to get closer to them. Promise. Then that behavior will go away - or at least, severely diminish - and she will start trying new things to get closer to other dogs. She probably won't give up, but that's okay. I just need to be there when it happens, to guide her to the different behaviors I want.