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PIXBRAIN HOME _ _ MOD 2 HOME _ _ previous _ _ FIGURE 2-17 _ _ next _ _ I WANT TO - - The neural axis may be pictured as a line which runs along the length of the neural tube and it is indicated by a red line this view. Directional terms use this axis as a reference and are summarized on this view. In general, these words have meanings which are already familiar to you from Gross Anatomy, but there is one exception. In describing the brain, the terms anterior and posterior are the equivalent of rostral and caudal (whereas in the body they are synonymous with ventral and dorsal). - - The neural axis is a relatively straight line in four-legged creatures, but in humans it has a definite bend , with most of the bending taking place at the level of the midbrain . This is even more apparent when one looks at views of the developing brain. It corresponds to the cephalic flexure in Blumenfeld's Figure 2.2 B. This bending of the neural axis creates one minor problem and one major one. 1) The direction, specified by such terms as ventral and dorsal, changes in an absolute sense, as one passes from one division of the brain to another. Clearly, the ventral-dorsal plane of the medulla in man is not parallel to the ventral-dorsal plane of the diencephalon. This is a bit odd, but causes no real difficulty.
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