Ganglia are primarily made up of
somata and
dendritic structures, which are bundled or connected. Ganglia often interconnect with other ganglia to form a complex system of ganglia known as a
plexus. Ganglia provide relay points and intermediary connections between different neurological structures in the body, such as the
peripheral and
central nervous systems. Among vertebrates there are three major groups of ganglia: •
Dorsal root ganglia (also known as the spinal ganglia) contain the cell bodies of
sensory (afferent) neurons. •
Cranial nerve ganglia contain the cell bodies of cranial nerve neurons. •
Autonomic ganglia contain the cell bodies of
autonomic nerves. In the autonomic nervous system, fibers from the
central nervous system to the ganglia are known as
preganglionic fibers, while those from the ganglia to the effector organ are called
postganglionic fibers.
Basal ganglia The term "ganglion" refers to the
peripheral nervous system. However, in the brain (part of the
central nervous system), the
basal ganglia are a group of
nuclei interconnected with the
cerebral cortex,
thalamus, and
brainstem, associated with a variety of functions: motor control, cognition, emotions, and learning. Partly due to this ambiguity, the
Terminologia Anatomica recommends using the term 'basal nuclei' instead of 'basal ganglia'; however, this usage has not been generally adopted.
Pseudoganglion A pseudoganglion is a localized thickening of the main part or trunk of a nerve that has the appearance of a ganglion but has only nerve fibers and no nerve cell bodies. Pseudoganglia are found in the
teres minor muscle and
radial nerve. ==See also==