All current majors have the option of following the new core sequence requirements.
You will not have to go back and take Cog Sci 1 as a prerequisite course. Some core courses, used as electives, will fit into the specializations. A new course under the number of 108C will be offered to provide students with additional programming experience using techniques of importance to cognitive science. It is probably best to take the first two courses of each sequence, however, depending upon your focus and other factors such as elective courses you may have already taken, there will be some leeway. Some prerequisites are recommended, rather than required.