Introduction to the Human Brain
The central nervous system (CNS) (Figure 12-2) is central in both location and function.
The human central nervous system (CNS).
The fully formed CNS can be considered in two major subdivisions:
the spinal cord
The human brain (Figures 12-3 and 12-4) has three major subdivisions:
Label The Brainstem
The brainstem is the core of the brain.
We consider it in three parts--the hindbrainstem, the midbrainstem, and the forebrainstem.
In general, the brainstem is made up of many nuclei and fiber tracts.
It is a primary coordinating center of the human nervous system.
Label The Cerebellum
Over the hindbrainstem is the cerebellum.
The cerebellum is connected to both the midbrainstem and the hindbrainstem.
The cerebellum is the primary coordinating center for muscle actions.
Here, patterns of movements are properly integrated.
Thus, information is sent to the appropriate muscles in the appropriate sequences.
Also, the cerebellum is very much involved in the postural equilibrium of the body.
Label The Cerebrum
The two cerebral hemispheres are attached to the forebrainstem.
Together, these two hemispheres make up the cerebrum.
Among related species, the cerebrum is the newest development of the brain.