Figure 2. Chartings (A­E) of orthograde labeling which resulted from a BDA injection into the left CVLM (B, C). Most of the labeled medullospinal projections descend ipsilaterally (solid arrows) into cervical levels of the spinal cord (D, E). In addition, however, some decussating fibers are present in the rostral (A) and caudal (B, C) medulla, as well as within the spinal cord (E; small solid arrows). Axons descending contralaterally through the medulla (A, B) are primarily found lateral to the inferior olivary nucleus (open arrows), and subsequently are observed within the ventral (open arrow) and lateral funiculi (D­E). Charting E (based upon enlargement of charting D) illustrates the locations of retrogradely labeled neurons (dots), which resulted from CTb-HRP injections into the right side of the diaphragm, and their relationships with the BDA-labeled medullospinal axons.