Cervical Autonomic Nervous System

Question 1

Are autonomic pathways afferent or efferent?

Answer 1

Efferent

Question 2

What is the difference between afferent and efferent?

Answer 2

Afferent - travels from periphery to CNS
Efferent - travels from CNS to periphery

Question 3

How do neurones synapse in autonomic pathways

Answer 3

2 neurones which synapse at a ganglion
Preganglionic and postganglionic

Question 4

Which neurones in autonomic pathways are myelinated?

Answer 4

Preganglionic neurones are myelinated, postganglionic are not

Question 5

What neurotransmitters are used for communication in the ANS?

Answer 5

Acetylcholine
Noradrenaline

Question 6

What are acetylcholine and noradrenaline releasing fibres known as?

Answer 6

Acetylcholine releasing - cholinergic
Noradrenaline releasing - adrenergic

Question 7

What is a ganglion?

Answer 7

A collection of nerve cell bodies within the PNS

Question 8

Where are preganglionic neurones found in the PS NS and where do they travel?

Answer 8

Craniosacral:
Cranial nerves III, IV, IX and X
Spinal segments S2 - S4
Travel to ganglia located close to target organ

Question 9

Where are preganglionic neurones found in the sympathetic NS and where do they travel?

Answer 9

Thoracolumbar - Spinal segments T1 - L2 specifically in the lateral horn
Travel to paravertebral and prevertebral ganglia close to CNS

Question 10

How is the sympathetic chain formed?

Answer 10

Paravertebral ganglia extend from the base of the skull to the coccyx where the left and right chains join at the ganglion impar

Question 11

What forms the stellate (star shaped) ganglion?

Answer 11

The fusion of the C7 and T1 ganglia

Question 12

How do all preganglionic sympathetic neurons first travel?

Answer 12

They leave the spinal cord through the ventral root
Form part of a spinal nerve
Enter the ganglia of the sympathetic chain via the white ramus communicans

Question 13

Which different routes can preganglionic sympathetic neurones take?

Answer 13

1. Synapse in the ganglia at the same level with a postganglionic neuron that exits through the grey ramus communicans
2. Travel up or down the chain to synapse in a ganglion at a different level with a postganglionic neurone that exits through the grey ramus communicans
3. Exit the ganglia via a splanchnic nerve to a prevertebral ganglion where it will synapse with a postganglionic neurone

Question 14

What are the cervical ganglia and where are they found?

Answer 14

Superior cervical ganglion at C1/C2
Middle cervical ganglion at C6
Inferior cervical ganglion at C7

Question 15

The superior cervical ganglion supplies its branches via what?

Answer 15

ICA and ECA (forming plexuses)
Cervical spinal nerves (C1-C4, cervical plexus)
Pharynx
Superior cardiac nerves

Question 16

The middle cervical ganglion supplies its branches via what?

Answer 16

Cervical spinal nerves (C5, 6)
Middle cardiac nerves

Question 17

The inferior cervical ganglion supplies its branches via what?

Answer 17

Vertebral artery (forming a plexus)
Cervical spinal nerves (C7 - T1;C7 and C8 to brachial plexus)
Inferior cardiac nerves

Question 18

What do the cervical ganglia regulate sympathetic innervation of?

Answer 18

Eyes (pupil dilation)
Eyelids
Lacrimal glands
Carotid body
Salivary glands
Sweat glands

Question 19

What is Horner’s syndrome?

Answer 19

Damage to cervical sympathetic trunk resulting in the absence of sympathetically stimulated functions on ipsilateral side of head

Question 20

What are the possible effects of Horner’s syndrome?

Answer 20

Constriction of pupils (miosis)
Drooping of superior eyelid (ptosis)
Vasodilation and absence of sweating on face/neck (flushed face and anhydrosis)

Question 21

Where do splanchnic nerves synapse?

Answer 21

With postganglionic neurones in prevertebral ganglia
Ventral to the aorta and named based on the vessels they lie near to:
Celiac
Superior mesenteric
Inferior mesenteric ganglia

Question 22

Describe the adrenal medulla

Answer 22

(Suprarenal gland) located superior to the kidney
Has an outer cortex and an inner medulla

Question 23

What supplies the adrenal medulla and how do these nerves synapse?

Answer 23

Sympathetic preganglionic neurones
These synapse with Chromaffin cells in the adrenal medulla that release adrenaline (80%) and noradrenaline (20%) into the bloodstream

Question 24

Describe the path of pre and postganglionic CN III neurones in the PS nervous system

Answer 24

Preganglionic neurones travel from Edinger-Westphal nucleus in the brainstem to the ciliary ganglion
Postganglionic neurones travel to innervate the ciliary muscle and sphincter pupillae (controls pupil)]

Question 25

Describe the pathway of CN VII in the PS nervous system

Answer 25

Sup salvatory nucleus in the brain stem to pterygopalatine ganglion and submandibular ganglion
Pterygopalatine ganglion to the lacrimal gland and nasal mucosa (via greater petrosal nerve)
Submandibular ganglion to submandibular gland via chorda tympani

Question 26

Describe the pathway of CN IX in the PS nervous system

Answer 26

Inferior salvatory nucleus to the otic ganglion
Otic ganglion to the parotid gland via the auriculotemporal nerve

Question 27

Where is the ciliary ganglion located?

Answer 27

Between the optic nerve and the lateral rectus muscle

Question 28

Where is the pterygopalatine ganglion located?

Answer 28

Within the pterygopalatine fossa

Question 29

Where is the submandibular ganglion located?

Answer 29

Suspended from the lingual nerve, close to the submandibular gland

Question 30

Where is the otic ganglion located?

Answer 30

Directly below the foramen ovale

Question 31

Describe the pathway of CN X in the parasympathetic nervous system

Answer 31

Presynaptic neurones travel from the dorsal nucleus of vagus nerve and nucleus ambiguus
Found within the carotid sheath
Synapse with postganglionic fibres in ganglia close to or within the target organ

Question 32

What are the divisions of the nervous system?

Answer 32

Central (brain and spinal cord) and peripheral (motor neurones and sensory neurones)
Motor neurones (somatic and autonomic)
Autonomic (sympathetic and parasympathetic)