Are parasympathetic fibers coming from the EW nucleus classified as pre-ganglionic or post-ganglionic?

The parasympathetic fibers originating from the Edinger-Westphal (EW) nucleus are classified as pre-ganglionic. This is because these fibers arise from the central nervous system, specifically from the brainstem, and travel to ganglia where they synapse with post-ganglionic neurons.

In the case of the EW nucleus, the pre-ganglionic fibers extend to the ciliary ganglion, which is located in the orbit. Here, they synapse with the post-ganglionic neurons that innervate the constrictor pupillae muscle and the ciliary muscle of the eye, facilitating functions such as pupil constriction and accommodation.

This distinction is fundamental in understanding the anatomy and physiology of the autonomic nervous system, specifically how signal transmission occurs from the central nervous system to peripheral effectors. Pre-ganglionic fibers are typically longer in parasympathetic pathways and have a relatively close synapse to the target organs.