easy way to learn nerve fibers

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SDNers,

I am overwhelmed with the innervation of the body for anatomy class. Unfortunately my professors didn't do a good job explaining the basics.

Does anyone out there know any easy ways or any tutorials to learn the types of nerve fibers that innervate parts of the human body? For example pericardiocophrenic nerve to pericardium and diaphragm: what fibers? GSA GSE, GVA, GVE, pre/post-ganglionic parasympathetic, pre/post-ganglionic sympathetic?

Thanks!!!

 

[DrBuzzLightYear]

for the boards you really only need "3-4-5 keeps the diaphragm alive" and "some say money matters but my brother says big booty matters most"

 

[omarsaleh66]

I used one of the first chapters in Moores. Maybe that will help.
just kinda knowing what each of them do will help u make sense of it all.

Parasympathetic are all in the head or sacral, their preganglionic nerves are long and go all the way to the target and synapse at the ganglia and then a small postgangionic nerve
- For example, the parasympathetic nerver (vagus ) will travel all the way down to the heart, (the ganglion) will be right there in the heart or by the heart, it will synapse, and then the small postganglionic nerve comes out and goes to the heart.

Sympathetic on the other hard have all their ganglia along the sympathetic chain close T1-L(?). The point is that it is close to your spinal cord, so here your preganglionic is small (opposite of parasympathetic) and travels a short distance to synapse at this chain THEN it travels a looong way as a post ganglionic to your target cell (like the heart) for example.

See they are kinda like opposites in structure and in fucntion. Sympathetics for stressful situations, Parasympathetic for when u are resting.

GSA is the things u feel, somatic is things u are control of, ur sensory. U touch something, that's ur GSA. Your GSE is efferent so it is going away from the spinal cord so thats like your body is carrying out an order. Pick up this cup!! Thas your GSE. The afferents are generally in the back (sensory) of the spinal cord or in the front (ventral) for the efferents.

GVE, GVA is visceral, these are out of your control. You cant control how your stomache feels when it is growling from hunger (GVA) or u cant help it when your stomache undergoes peristalsis to digest food (GVE). These are out of your control, your heart beating, bronchioloes constricting, dilating, etc.. these are found at the side of the spinal cord (lateral).


Now, I dont know if all of this is right, but hopefully u'll get some of an idea, I forgot alot of this stuff so if I made mistakes, sorry, read the book to really grasp it.

later

Omar

 

[manwhoisthursdy]

Unfortunately its harder in Head and Neck. Some hints:

SOUND AND SIGHT are SSA (special somatic afferent). That's optic nerve and vestibulocochlear nerve.

The other special senses (smell and taste) are SVA (special visceral efferent). That's chorda tympani nerve (from facial) and olfactory nerve. When my food tastes or smells good I go "sva!!". Not really, but that's my ******ed mneumonic. :-D

Touch sensation (cutaneous) is GSA (like everywhere else).

There's also SVE, which is just something to memorize. The trapezius and sternocleidomastoid receive motor from CN XI, which may be either GSE or SVE, it's controvertial. It's GSE (like in the body) if those muscles come from somites, but it's SVE if they come from pharyngeal arches.

The "S" for special always indicates that the innervates stuff comes from the pharyngeal arches. So the facial nerve's fibers that innervate muscles of facial expression are SVE. The recurrent laryngeal nerve (branch of CN X), which innervates muscles of speech, is also SVE.

Then there's GVE/GVA. The GVE is either PREganglionic parasympathetic (found in the head, like CN X, or from the sacrum, like the pelvic splanchnics), or POSTganglionic sympathetic (thoracolumbar, these fibers are found in the vast majority of spinal nerves). Exception: splanchnics (except the pelvic splanchnics!!) are PREganglionic sympathetic, because they come right off the sympathetic trunk w/o synapses. GVA fibers just run with GVE fibers of any type.

Remember pelvic splanchnics are parasympathetic and sacral splanchnics are sympathetic. The pelvics come from the spinal roots, and the sacrals come of the sympathetic trunk.

hope this was helfpul! please correct me if I made any mistakes.

 

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Thanks Omar and Manwhoisthursdy! I have a feeling that I am going to be spending a lot of time on this part of anatomy.

Does anyone out there have a good website for this nerve stuff to supplement my textbooks?

 

[Heal&Teach]

for the boards you really only need "3-4-5 keeps the diaphragm alive" and "some say money matters but my brother says big booty matters most"

In addition, S2-3-4 keeps the penis off the floor 🙂

Sympathetic/parasympathetic innervation to genitalia are not antagonistic as the case is for most other systems. Another phrase that may help is "point and shoot" - P for point, parasympathetic, and S for shoot, sympathetic.

Also, all splanchnics (greater, lesser, sacral, pelvic) are pre-ganglionic.

Sympathetic - thoracolumbar (originate from thoracic and lumbar nerves)
Parasympathetic - craniosacral (originate brainstem and sacral nerves)

The autonomics of the head and neck were helpful in learning the overall scheme of things, and I found it difficult to learn what fibers were going where without knowing their origination.

When thinking about nerves that go to or come from a ganglion (e.g., otic, pterygopalatine, etc.), they go in as presympathetic, and synapse on the ganglion so that fibers leaving it are post-ganglionic (e.g., greater petrosal nerve carries taste/sensory fibers to the pterygopalatine ganglion, so that nerves leaving the ganglion, like the palatines, leave with taste fibers).

Hope that wasn't too confusing (and I'm sure that I got something wrong somewhere in there)!