“…The PPN also projects to multiple thalamic nuclei including the ventral posterior thalamus (Smith et al, 1988, Steriade et al, 1988, Lavoie and Parent, 1994b, Newman and Ginsberg, 1994, Erro et al, 1999) and is reciprocally connected with multiple basal ganglia nuclei (Parent and Smith, 1987, Lavoie and Parent, 1994b, a, Charara et al, 1996). Descending projections include primarily non-cholinergic efferents to the cervical and thoracic spinal cord (Goldsmith and van der Kooy, 1988, Rye et al, 1988, Spann and Grofova, 1989, Skinner et al, 1990a, Aravamuthan et al, 2007) and primarily cholinergic efferents to the pontine and medullary reticular formations (Garcia-Rill and Skinner, 1987, Skinner et al, 1990b, Takakusaki et al, 1996, Whelan, 1996, Jordan, 1998, Garcia-Rill et al, 2001) including projections to a large portion of medullary reticulospinal neurons (Garcia-Rill and Skinner, 1987). It is these reticulopsinal connections that are thought to mediate the induction of locomotion (Grillner and Shik, 1973, Steeves and Jordan, 1980, Noga et al, 1991, Whelan, 1996, Jordan, 1998, Noga et al, 2003, Dai et al, 2005) and the changes in postural and limb tone (Takakusaki et al, 1994, Takakusaki et al, 2003, Takakusaki et al, 2004a, Takakusaki et al, 2004b) noted with PPN chemical or electrical stimulation.…”