My experience with house training Isabella reminds me of a story someone once told about the experience of training a pet monkey to use the potty. Every time the monkey would have an "accident," the owner would say "No! no!," pick it up and make it sit on the potty. Then he would praise the monkey and give it a treat. The long and short of it was, the monkey learned to run and sit on the potty without fail — every time — after it had already done its business.
Well, we are having a similar experience. I’ve been training Isabella to use a cat litter box, very successfully I might add! Every time we take her out of her kennel, the very first thing we do is take her to her litter box and praise her and give her a treat when she uses it. Lately, she has been using it all the time, getting lots of praise and occasional treats. Except yesterday I noticed she "used" her litter box about three times a row, in quick succession. And after each visit, she would run to me and beg for a treat.
I figured out she has me trained, to give her a treat every time she goes in the litter box.