Figure 2. Glutamate levels in the posterior insula are negatively correlated with experimental pressure pain testing.
Medium pressure thresholds from fibromyalgia patients (solid circles) and control patients (open circles) are displayed in this scatterplot, along with a regression line across both groups. Fibromylagia patients demonstrated higher central glutamate levels and corresponding lower pain thresholds; however, the correlation between higher glutamate levels and lower pain thresholds was also demonstrated in the control group. Glx = glutamate (From Harris, R.E., et al., Elevated insular glutamate in fibromyalgia is associated with experimental pain. Arthritis Rheum, 2009. 60(10): p. 3146-52 with permission)
