<p>You wouldn’t be able to design a major, because there are already programs for behavioral neuroscience and neurobiology. Special division majors are for disciplines that don’t have an established program. Both tracks (in the psych and MCDB dept, respectively), are fairly popular. “Tracks” at Yale mean that you take many of the same courses for the major, but substitute or add additional courses to specialize in a given area. You can see the requirements for each track under their associated majors at [Subjects</a> of Instruction | Yale College Programs of Study](<a href=“Yale College”>Yale College)</p>