Figure 2.

Windup pain ratings of normal control (NC) and fibromyalgia syndrome (FM) patients. All subjects received 15 mechanical stimuli (taps (T)) to the adductor pollicis muscles of the hands at interstimulatory intervals of 3 s and 5 s. FM patients showed mechanical hyperalgesia during the first tap and greater temporal summation than NCs at both interstimulatory intervals. A numerical pain scale was used (0 to 100). The shaded area represents pain threshold.