Preganglionic nerves from the thoracic spinal cord enter into the cervical ganglions and synapse with its postganglionic fibers or nerves.

The cervical ganglion has three paravertebral ganglia: Nerves emerging from cervical sympathetic ganglia contribute to the cardiac plexus, among other things.

Unlike all other ganglia, the medial branches of the cervical ganglia are 95% postganglionic axons.

Wilson-Pauwels, Linda; Stewart, Patricia A.; Akesson, Elizabeth J.

Canada: B. C. Decker, Inc. pp. 71–104.