Why does this dog run in circles?

I Just read an article about shelter puppies in a publication by the Humane Society called "All Animals" The name of the article was "Life Outside the Cage" and it was featured in the November/December 2010 issue. It describes your friend's dog to a "T". I'll bet the shelter she got her from rescued her from a puppy mill. Please try to find this article. It will open your eyes as to what kind of life this pup must have had and help your friend find the patience to help her adapt to her new life. God bless your friend for going to a shelter instead of a pet store!