That happened to me at UCSF, which is closed file. I was like.... Ok... what now.
I just started with... "Well, I grew up in the Bay Area... I went to high school in the city. It was kind of odd driving across the Golden Gate Bridge this morning and seeing kids in their cars heading towards (my high school). It didn't seem that long ago when I was doing it and well, it kind of frieked me out." Then I talked about why I chose my college, why I chose what i studied. Later on I talked a little bit about my childhood and the impact of growing up in San Francisco during the HIV epidemic. Talked about losing friends to AIDS and my mom being in the hospital at UCSF. As a kid, I thought the building we were sitting in was kind of creepy. [The ambulatory care building is all black glass and at night you can see people walking around the halls because the halls are on the outer perimeter of the building] I still do think it is creepy looking.
SO..... my point is, relax, be yourself, talk about what you think is important, but DON'T rehearse an answer because people can always tell. Interviews are conversations not rehearsed plays. I got in too so I think my tactic worked.