Factor analysis of VARIMAX rotated QST data after 4 Hz matrix array stimulation.

<p>All mechanical pain thresholds (MPT, MPS, WUR, PPT) show significant loadings on factor 1 “mechanical pain” (x-axis). Thermal pain thresholds show significant loadings on factor 2 “thermal pain” (y-axis), while thermal and mechanical detection thresholds take an intermediate position, indicating that 4 Hz stimulation differentially effects different peripheral and central sensory channels to the brain.