The pathway taken by the nerve impulse in mediating this simple response is in the form of a two-neuron arc that begins and ends in the periphery. Many of the actions of the nervous system can be explained on the basis of such reflex arcs, which are chains of interconnected nerve cells, stimulated at one end and capable of bringing about movement or glandular secretion at the other. The Nerve Network. The cranial nerves connect to the brain by passing through openings in the skull, or cranium. Nerves associated with the spinal cord pass through openings in the vertebral column and are called spinal nerves.
Most nerves are mixed nerves made up of both sensory and motor elements.
In addition to supplying structures in the neck, the vagus is distributed to structures located in the chest and abdomen. Vision, auditory and vestibular sensation, and taste are mediated by the second, eighth, and seventh cranial nerves, respectively. Cranial nerves also mediate motor functions of the head, the eyes, the face, the tongue, and the larynx, as well as the muscles that function in chewing and swallowing. Spinal nerves, after they exit from the vertebrae, are distributed in a bandlike fashion to various regions of the trunk and to the limbs. Autonomic Nervous System.