Figure 3. Normalized peak-to-peak amplitude of stretch reflexes in left (A) and right (B) masseter and left (C) and right (D) temporalis muscles evoked at different displacements. Note: The stretch velocity of 25 mm/sec is constant, since the ramp time is adjusted accordingly. Mean values + SEM (n = 11). Two-way ANOVAs indicated significantly higher amplitudes during the pain condition compared with the pre- and post-pain conditions in the right masseter.