118 LABORATORY OUTLINE OF NEUROLOGY 



the internal capsule. These are descending fibers from the 

 gyrus centralis anterior. 



151. Brachium Conjunctivum. Finally, tear the fibers of the 

 brachium conjunctivum downward to their decussation under 

 the aqueduct of Sylvius. The red nucleus or nucleus ruber 

 (where these fibers end after decussating) will be seen imme- 

 diately in front (cephalad) of this decussation, as a round gray 

 mass about the size of a pea, not far from the median plane. 

 Its rubro-thalamic tracts can readily be seen by teasing for- 

 ward from the nucleus. 



12. Recapitulation of Conduction Paths 



152. Thalamic Nuclei. Now make a list of the nuclei of the 

 diencephalon which you have seen and tabulate their fiber 

 connections. 



153. Finally, having completed the Table of Conduction 

 Pathways (Section 101) and a table or diagram of the olfactory 

 tracts (Section 130), make a systematic review of each func- 

 tional system of tracts. For each system get a clear picture of 

 the course of the nervous impulses involved in both the reflex 

 and the cortical functioning of that system. With the intact 

 human brain before you, try to visualize the courses of the 

 fiber tracts in question with reference to the external land- 

 marks. 



