How does Brian Yorkey use imagery in Next to Normal?

The most interesting thing about the setting of this piece of theatre is that it moves in and out of reality - specifically, in and out of actual physical settings (i.e. the family's home, the doctor's office, the operating room), in and out of the characters' minds. The most vivid, and dramatically effective, of the latter is the relationship between Diana and Gabe, which takes place almost entirely within the boundaries of Diana's imagination; he's not alive, he is a delusion, a product of her imagination and fantasy ... a product of her mind. Here it's important to note that while Diana is the only character who interacts with Gabe directly, his presence is also a manifestation/externalization of the minds of the other characters - Dan's memory and assumptions, Natalie's memory and resentments. In that sense, the scenes with Gabe could also be viewed as projections of their minds, as being set in their minds. Ultimately, though, the setting of this piece of theatre is a product or manifestation of the possibilities inherent in theatre as a whole; as previously discussed, in theatrical narrative, realities can become layered, or be experienced as layered, in ways that they can't be in film or in written narrative. A setting can provide physical environment for events in the past and in the present at the same time, and this is a vital component of the setting for Next to Normal. Its setting in a theatrical environment, in a theatrical context, enables its story to unfold in a way relevant to the experience of its characters and particularly to the experience of its central character, Diana, that it would otherwise be less able to effectively invoke.