New Model of Human Red Nucleus Figure 10. Human red nucleus and its surrounding structures. Upper photomicrographs (A-H) showing distribution of myelinated fiber bundles stained by myelin stain in the human mesodiencephalic structure of successive serial sections. Section A is the most rostral. The human NB is the dorsomedial cell-rich area of the red nucleus. Scale bar = 500 mm in H (also applies to A–G). Lower scale drawing showing the distribution of Nissl- stained cells found in the human mesodiencephalic structure as indicated by dots in the drawings of 15 successive serial sections. Section 1 is the most rostral. Sections 13 and 14 show giant mNr cells as large dots indicated by arrowheads. The number in the left corner of each photomicrograph and drawing is the rostrocaudal distance (in micrometers) from the rostral tip of the red nucleus. (A) – (H) correspond to Figs. 11A–H. CTT–central tegmental tract, dmpNr–dorsomedial part of parvicellular red nucleus, EW–Edinger-Westphal nucleus, FR–fasciculus retroflexus, MLF–medial longitudinal fasciculus, mNr–magnocellular red nucleus, MTT–medial tegmental tract, NB–nucleus accessorius medialis of Bechterew, ND–nucleus of Darkschewitsch, SCP–superior cerebellar peduncle, vlpNr–ventorlateral part of parvicellular red nucleus, III–oculomotor nucleus, IV–trochlear nucleus. doi:10.1371/journal.pone.0006623.g010 PLoS ONE | www.plosone.org 12 August 2009 | Volume 4 | Issue 8 | e6623