If you haven't read Elaine Scarry's The Body in Pain: The Making and Unmaking of the World, you should.
Scarry's excellent book on the violent metaphors and rhetoric associated with the human body explores the political consequences of deliberately inflicting pain (physical, emotional, and psychological) on another human being. The text was published in 1985 and it is sad how appropriate it is today given recent revelations of American Government's policies and attitudes toward torture between 2001 and 2008.
Here's just a sample:
"As the body breaks down, it becomes increasingly the object of attention, usurping the place of all other objects, so that finally [...] the world may only exist in a circle two feet out from [the victim].
[...] The voice becomes a final source of self-extension; so long as one is speaking, the self extends out beyond the boundaries of the body, occupies a space larger than the body" (33).
In torture, there is an attempt to remove another from their body. Their voice the only salvation which allows them to return to that body, which becomes a much worse prison than any external structure. There is no escape from the pain; it is literally "incorporated" into the body and yet the victim of torture longs to return to the body, and is terrified to do so.
That is the nightmare that is torture. A disembodied psyche which fears and longs for the internal privacy of the body but both spaces (internal and external) are no longer safe.
Really. You should read the book. In addition to the first chapter, "The Structure of Torture," it has some great material on the "Structure of War" (Ch 2) and "The Structure of Belief" (Ch 4).
Definitely Foucauldian (and thereby quasi-Marxist) in its philosophical underpinnings (distribution of power) it is an excellent treatise on the body as both a surface and a vessel, a shell and an imaginary space.
Think about the last time you were in physical pain. You (hopefully) knew it would pass and you knew that it was not created by someone outside yourself. For those who are tortured pain becomes the normative state of the body and the mind--and there is no escape, no reprieve, no release from that pain.