Hey people... ignore that figure 1 and all the blue numbers on my last post. I copy paste that section... : )

Reference
http://www.medscape.com/viewarticle/562363_5
psy.ucsd.edu/~dmacleod/159/presentations05/AnaPain.ppt
http://www.anaesthetist.com/icu/pain/Findex.htm#index.htm