Anatomy of the Nervous System

Dr. Alan H. Teich

Terms for anatomical directions in the nervous system. In four-legged animals dorsal and ventral point in the same direction for the head as they do for the rest of the body. However, human’s upright position has tilted the head relative to the spinal cord, so the dorsal and ventral directions of the head are not parallel to the dorsal and ventral directions of the spinal cord.

A sagittal section through the human brain

The limbic system is a set of subcortical structures that form a border (or limbus) around the brain stem

The basal gangliaThe thalamus is in the center, the basal ganglia are lateral to it, and the cerebral cortex is on the outside.

The cerebral ventriclesDiagram showing positions of the four ventricles.

Some major subdivisions of the human cerebral cortexThe four lobes: occipital, parietal, temporal, and frontal.

The Homunculus

The human brain stemThis composite structure extends from the top of the spinal cord into the center of the forebrain. The pons, pineal gland, and colliculi are ordinarily surrounded by the cerebral cortex.

Circle of Willis

Circle of Willis

Diagram of a cross section through the spinal cordThe dorsal root on each side conveys sensory information to the spinal cord; the ventral root conveys motor commands to the muscles.

Sympathetic Nervous system

Parasympathetic Nervous System