168 



HUMAN PHYSIOLOGY 



The functions of this segment of the brain are chiefly 

 conducting, but the anterior corpora quadrigemina forms the 

 shunting station between the incoming fibres of the optic 

 tract and the oculo-motor mechanism (see p. 126). 



FlG. 91. Diagrammatic Horizontal Section through Base of Cerebral Hemisphere, 

 showing (1) the Outgoing Fibres for the Leg, Arm, and Face springing from 

 the Cortex of the Rolandic Areas, passing through the Internal Capsule 

 between the Thalamus and the Lenticular Nucleus. The Face Fibres cross in 

 the Pons, the Leg and Arm Fibres in the Medulla. (2) The Incoming Fibres 

 (Fillet, Eye) form their stations in the Thalamus, and then pass on to the 

 Cortex. 



F. THE CEREBRUM. 



Each peduncle terminates in its half of the cerebrum. 

 As the fibres pass from peduncle to cerebrum and vice versa 

 they come into relationship with three masses of grey matter 

 lying in the midst of the cerebrum. These are the thalamus 

 options into which the ingoing fibres enter; the lenticular 

 nucleus, between which and the thalamus the outgoing 



