Immediately after I had this thought, I had the feeling that somehow, somebody had gotten inside the MRI machine with me—and that the space had strangely expanded, to at least the size of a two-man tent, and possibly much larger.
 
An image flashed into my mind of an illustrated Classic Comics version of The Count of Monte Cristo that I had read when I was a kid.  After an excruciatingly difficult effort to tunnel his way out a fortress in which he has been unjustly confined, the protagonist finally breaks through a prison wall to find not the outside world, but just an older man’s cell.  

In the course of their association, though, the older man frees him in a different and deeper way, by teaching him all kinds of things about the outside world that the protagonist would never have learned in the normal course of his life.
 
I felt very much the same way for the remainder of the MRI.  Although I never got the sense that anybody was directly teaching me things like fencing or world history, just by being in the presence of my rescuer, I felt much more free.  And as the desperate urge to escape subsided, my breathing fell naturally into a pattern where the gag reaction subsided, without my needing to constantly think about how to breathe to prevent it.