Anatomy of the Sympathetic Nervous System

Question 1

What is the difference in the specificity of the responses brought about by the parasympathetic and sympathetic nervous systems?

Answer 1

Parasympathetic - localised

Sympathetic - mass response

Question 2

Describe the outflow of the sympathetic nervous system.

Answer 2

Thoracolumbar - T1 - L2/L3

Question 3

Other than the dorsal and ventral horns, what other feature do parts of the thoracolumbar spinal cord have?

Answer 3

Lateral Horn - where the sympathetic preganglionic fibres originate

Question 4

What is the difference between the White and Grey rami communicantes?

Answer 4

White - going into the sympathetic trunk

Grey - going out of the sympathetic trunk

Question 5

What is the difference in the direction of ventral and dorsal flow?

Answer 5

Ventral - OUTflow

Dorsal – Inflow

Question 6

What can happen to the preganglionic neuron once it reaches the sympathetic ganglion via the white ramus?

Answer 6

It can travel up and down the sympathetic trunk and synapse in another ganglion at a different level.
It can synapse at that particular ganglion.
It can go through the ganglion and synapse in a subsidiary ganglion (e.g. coeliac ganglion or superior mesenteric ganglion)

Question 7

State the number of ganglia in each of the four regions.

Answer 7

Cervical = 3
Thoracic = 11/12
Lumbar = 4/5
Pelvic = 4/5

Question 8

Where do the splanchnic nerves arise and where do they go?

Answer 8

They originate in the thorax and move down to the abdomen through the diaphragm. You get the greater, lesser and least splanchnic nerves.

Question 9

Describe the outflow of the parasympathetic nervous system.

Answer 9

Craniosacral

Question 10

State the levels of the sacral outflow and the nerves they go through.

Answer 10

S2-S4

Goes to pelvic viscera via pelvic splanchnic nerves

Question 11

How many pairs of cranial nerves are there?

Answer 11

12

Question 12

What four cranial nerves make up the cranial parasympathetic outflow?

Answer 12

Occulomotor, facial, glossopharyngeal, vagus

Question 13

Where is the ganglion of the occulomotor nerve (III)?

Answer 13

Ciliary ganglion

Question 14

What does the facial nerve (VII) innervate? State the ganglia of the facial nerve.

Answer 14

Facial muscles and two of the three salivary glands (submandibular and sublinguinal glands)
Ganglia: submandibular and pteropalatine

Question 15

What does the glossopharyngeal nerve (IX) innervate and where is its ganglion?

Answer 15

Innervates the third salivary gland - parotid gland

Ganglion = Otic ganglion

Question 16

What structure does the vagus nerve go through in the neck?

Answer 16

Carotid sheath - contains the carotid artery and internal jugular

Question 17

State the two plexuses in the enteric nervous system and the layer in which they are found.

Answer 17

Submucosa = Meissner’s Plexus

Myenteric plexus = Auerbach’s Plexus

Question 18

What are the 6 parts of a neurological examination?

Answer 18

Appearance
Mental State
Gait and Station
Motor System
Cranial Nerves 
Sensation

Question 19

What are the two ways you can do an EMG?

Answer 19

Intracellular - determine the difference in potential (EMF) between inside and outside the axon
Extracellular - determine the difference in potential between two points (both outside the neuron) along a nerve

Question 20

What can an EEG be used to diagnose?

Answer 20

Alzheimer’s, Epilepsy, Tumour