There's an article on Alex, an intelligently communicative parrot, which makes me wonder about cognitive processes in both animals and humans. Roland Piquepaille has more information on the parrot and it's spontaneous, and correct, application of a word in a new context. Such a feat implies the animal may perform some cognitive tasks with the building blocks of language rather than just trained or instinctive response. This bird, of course, is not the only "talking" animal as there are other cases of animals learning our language like Koko the Gorilla. These talking animals lead towards a recursive question - think about how you think. With the ability of language, reasoning and thought processes take place in our language.
So I pose the question: at what point do thought processes switch over to being conducted in a given language? Are there studies to show brain patterns in animals to indicate whether or not they also "think" in the language they've learned?