Ganglion
Knot-shaped accumulation of nerve cells of the sympathetic and parasympathetic nervous system, in which the ganglionary synapses are located between the central and peripheral nerves of both systems.
The sympathetic ganglia (except for those for the digestive tract) are located in the sympathetic chain, the parasympathetic ganglia are mostly located near the successful organ (except for those for salivary glands and eye).