Nuclie are in the CNS, while ganglia are in the PNS.
gangia(n) (pluaral/singular)
A cluster of many nerve cells outside the central nervous system is known as a ganglion (plural ganglia). A cluster of nerve cells within the central nervous system is known as a nucleus (plural nuclei).
In the central nervous system, a collection of neuron cell bodies is called a nucleus.In the peripheral nervous system, a collection of neuron cell bodies is called a ganglion (plural: ganglia).The one exception to this rule that you may have encountered is the basal ganglia in the brain. Indeed, the basal ganglia technically should be called the basal nuclei, but they were named prior to the terms being defined and the name has stuck.
Autonomic ganglia contain the cell bodies of motor neurons.
In the peripheral nervous system, which is outside the central nervous system (CNS), collections of nerve cell bodies are called ganglia.
Ganglia
These collections are called ganglia. Ganglia often interconnect with other ganglia to form a complex system of ganglia known as a plexus.
Ganglion
Paravertbral ganglia (aka sympathetic trunk ganglia)
ganglia is a group of cell bodies in the PNS.
Dorsal root ganglia of the spinal chord gray matter.
Ganglia