I am having trouble articulating a statement of intent because of a few things. But to keep on point for Stack Exchange I'll focus only on one: interdisciplinary coursework.
I have spoken to a Fine Arts Department at my top choice and they not only permit but promote taking interdisciplinary courses. My intention is to take as many courses as I can in Psychology while doing the MFA, as well as any required training to use the Eye-Tracking facilities.
- Should I specify professors from both departments?
- Should I mention that after I complete the first degree (MFA in my case) I plan to pursue a PhD in the other field (Visual Cognition in my case)
- Should I state research goals in both fields or keep it to only the school I am initially applying to? (In my case: In the immediate I want to research neurotypical perception through visual design for clearly communicating complex ideas. Eventually though (as in during the PhD if not Post Doctorate) I want to research atypical perception and how to design visual communications that can be easily understood by people with disabilities. I am not sure which disability but mostly Autism Spectrum Disorders, however I also think there could be a strong use for this research in assisting those with Alzheimer's.)
How much of this cross disciplinary information should a person state in their Purpose Statement / Letter of Intent? My concern is that I don't want it to sound like I only want the Psychology Department and leave the committee wondering why I am going for the MFA in Design first.
I disagree with aeismail, but with some qualifications.
Generally, I encourage you to lay out your goals and overall plan, including both MFA and PhD. It's vital that you convey your thought process and justification for this plan, not just the plan. Is this an impulse? Or has it been many years in the making? Why does this plan suit you with your unique skills, capabilities, and disposition? Why does this plan fit the University and department that you are applying for? What about this plan is well known and what is uncertain and unknown?
For example, you should be able to answer this critical question: Why bother with the MFA first? Why not just enter an interdisciplinary PhD program now? What does the combination give you that neither, alone, would provide?
Have you evaluated the many Design Schools (D-Schools) at major universities? Stanford, MIT, and many others have these. If a PhD from these D-Schools won't meet your needs, explain why.
In all of this, what you are really communicating to the committee is what is unique about you for MFA and how you will be successful in the MFA program.
The qualification is that admissions criteria and process is very different for Masters vs. PhD. In Masters programs, no one cares whether you will be a valuable member of the academic research community. What they care about is: can you succeed in the course work (and thesis or capstone project, if required), and will you be a valuable contributor as member of the community of students. In PhD in Psychology, admissions is nearly always determined by whether you are the most attractive research assistant for one of the professors, given their interests and funding.
Therefore, when you write your Masters application, you need to emphasize how your preparation and previous academic work set you up for success in course work and engagement with other students.