http://video.google.com/videoplay?docid=-4...36913&hl=en
Search at 1hour and 29 minutes in the movie above. You will see how the confessions of Khalid Mohammed were obtained :
"Whatever we need to do to get the truth out"
"Block his breathing with an artificial respiration machine"
Also there is the mental torture : torturing his children in front of him or just threaten him that his children will be tortured.