“…This mechanism would, however, also be activated with other physical therapies such as massage (Kessler, Marchant, & Johnson, 2006). Manipulation also activates the descending pain inhibitory system from the dorsal periaqueductal (dPAG) gray (Skyba, Radhakrishnan, Rohlwing, Wright, & Sluka, 2003;Sluka, Skyba, Radhakrishnan, Leeper, & Wright, 2006). Wright (1995) demonstrated the effect of manipulation on this system by noting the specific responses of dPAG activation, most markedly being rapid analgesia.…”