Figure 2

Perceptual thresholds in the VM and control groups for (A) roll rotation about an earth-vertical axis; (B) inter-aural (IA) translation along an earth-horizontal axis; and (C) pressure thresholds measured with Semmes-Weinstein monofilaments72 at three locations (zygomatic arch, scapula, and iliac tuberosity, with the left and right-sided measurements averaged for each subject and location). Tactile thresholds were measured only in the VM and migraine groups since tactile sensitization related to allodynia was a potential concern in the two migraine populations but not in the normal control subjects.