Figure 2From: A preliminary fMRI study of analgesic treatment in chronic back pain and knee osteoarthritisBrain activity maps for CBP and OA. CBP and OA group average brain activity maps (fixed effects analysis) for session1 (prior to treatment), session 2 (2 weeks after application of Lidoderm) and contrast between before and after treatment (scan 1 > scan 2). Each scan map is a subtraction between the pain rating task and the control visual rating task.Back to article page