Figure 1

A. Example pain intensity rating for manually palpating painful arthritic joints (grey areas is duration of palpation). Right panel shows that the mean rating of pain intensity for palpating painful joints, which significantly decreased 1 and 3 hours after administration of COX-2i when compared to the baseline (p < 0.001). B. Brain activity in ten consecutive scans is presented for palpating painful joints (each column is a separate scan). The first 4 scans are prior to drug ingestion (pre COX-2i), the next four start 1 hour post drug ingestion, the last two are 3 hours post-drug ingestion. Four transverse slices are shown for each scan (top to bottom: z = -12, 10, 28 and 44). Note that brain activity decrease after cox-2i is evident in these individual scans. C. Average group activity minus visual controls using fixed effects analysis for palpating painful joints across all conditions (pre and post COX-2i). Activity is seen bilaterally in insular cortex and thalamus, in addition to right primary and secondary somatosensory areas and mid anterior cingulum. Activity maps are presented in MNI space, x y z coordinates in mm.