Neuronal Signaling and the Structure of the Nervous System
Dorsal view of the spinal cord and spinal nerves. Parts of the skull and vertebrae have been cut away; the ventral roots of the spinal nerves are
not visible. In general, the eight cervical nerves (C) control the muscles and glands and receive sensory input from the neck, shoulders, arms,
and hands. The 12 thoracic nerves (T) are associated with the shoulders, chest, and upper abdomen. The ﬁ ve lumbar nerves (L) are associated
with the lower abdomen, hips and legs, and the ﬁ ve sacral nerves (S) are associated with the genitals and lower digestive tract.
Redrawn from FUNDAMENTAL NEUROANATOMY by Walle J. H. Nauta and Michael Fiertag. Copyright © 1986 by W. H. Freeman and Company. Reprinted by permission.