Recent findings that spinal manual therapy (SMT) produces concurrent hypoalgesic and
sympathoexcitatory effects have led to the proposal that SMT may exert its initial effects by
activating descending inhibitory pathways from the dorsal periaqueductal gray area of the
midbrain (dPAG). In addition to hypoalgesic and sympathoexcitatory effects, stimulation of
the dPAG in animals has been shown to have a facilitatory effect on motor activity. This study
sought to further investigate the proposal regarding SMT and the PAG by including a test of …