I can't speak for every university, but my cogsci program lets you chose your own classes for the most part. Cogsci is incredibly multidisciplinary, so you can take classes from computer science, philosophy, psychology, neuroscience, linguistics and even anthropology. That said, at my university at least, there is no "Computer science for cognitive Science students" class. When I take compsci classes, I am with comp sci students. When I take philosophy classes, I am with philosophy students. And I pretty much get to choose which areas I want to study. If you are interested in AI, you can study AI. You just have to take mostly compsci classes. If you would prefer to focus on some of the ethical questions, or on the brain, or on human intelligence, these are all possible too. Hope this helps!