MODULE 2
VENTRAL and SAGITTAL VIEWS of the BRAINSTEM
- - Here, as elsewhere in this module, we include the diencephalon in our discussion of brainstem anatomy, even though - strictly speaking - it is not part of the region. Also, we may at times refer to the diencephalon as the thalamus, even though this is not quite right either. While unfortunate, this is the way people use these words. Take another look at Figure 2-2 if this is confusing.
- - In some respects, the anatomy of the ventral surface of the brainstem is relatively simple. Figure 2-13 shows the major landmarks that you should be able to identify. In line with the above, we have also included a few structures that are part of the diencephalon (mammillary body, etc.) and hemisphere (corpus callosum, etc). Keep this view on your screen and compare it with DiganatA_1.6. DiganatA_5.3 is a wonderful ventral view of a dissected brain and DiganatA_5.5 is an oblique view.
- - We don't want to get into the details regarding the cranial nerves, because we take the nerves up later in the course, but (for this module) you should be able to pick out each nerve and relate its point of exit from the brainstem to surrounding structures. Figure 2-14 gives you all you need to know, but DiganatA_5.10 is a view of them on a real brain.
- - Mid-sagittal views can also be helpful. Look at Figure 2-15 and compare it with DiganatA_5.2.
- - Figure 2-16 completes our list of brainstem images.
- - We are, in a sense, at the midpoint of the module. We have looked 7 dorsal views of the brainstem, 2 ventral views, 2 mid-sagittal views and one lateral one. In the process, we have identified more than 50 structures. To review the situation look at the module 2 glossary. We don't expect you to know anything about the function of these structures, but we do hope you will be able to identify most of them on the appropriate figure, once you finish studying this module. The best way to get to the glossary is to click on "I Want To" , which you will find somewhere in most views (including this one) . In that view, find the "X" for the module 2 glossary and click on it.