6.1 Autonomic Nervous System

Question 1

What is the autonomic nervous system?

Answer 1

Part of the peripheral nervous system that controls smooth muscle and glands

Question 2

Describe the outflow of the sympathetic system?

Answer 2

Thoracolumbar outflow

T1-L2

Question 3

Where can cell bodies of parasympathetic NS be found?

Answer 3

Lateral horn of grey matter of spinal cord

Question 4

Describe the outflow of the parasympathetic NS

Answer 4

Craniosacral

Cranial 4
Sacral S2-4 = pelvic splanchnics

Question 5

Where can cell bodies of parasympathetic NS be found?

Answer 5

Discrete collections of parasympathetic bodies in brainstem or within grey matter of sacral spinal cord

Question 6

What are nuclei?

Answer 6

Discrete collections of parasympathetic cell bodies

Question 7

What are the symptoms of Horner’s syndrome?

Answer 7

Partial ptosis
Constricted pupil
Anhidrosis

Question 8

Why do you get partial ptosis in Horner’s syndrome?

Answer 8

Only lost the sympathetic innervation

Oculomotor nerve still innervating the bulk of the muscles

Question 9

Why do you get a constricted pupil in Horner’s syndrome?

Answer 9

Lost the sympathetic effect of dilation

Miosis

Question 10

What is the origin of sympathetic innervation?

Answer 10

Spinal cord T1-L2

Question 11

Where are the important ganglia for sympathetic head and neck innervation?

Answer 11

Ganglia in cervical portion of sympathetic chain

• Superior cervical ganglion
• Middle cervical ganglion (neck and chest)

Question 12

What do sympathetics of head and neck hitch hike on?

Answer 12

Blood vessels
- External and internal carotid

CN V
- Distally

Question 13

What are the effector tissues of sympathetic innervation of head and neck?

Answer 13

Eye - Dilator pupillae
Eye lid - Superior tarsal muscle
Blood vessels
Sweat glands

Question 14

What are the responses of sympathetic innervation to head and neck?

Answer 14

Pupil dilation
Assists lid retraction
Vasoconstriction
Sweating

Question 15

Which cranial nerves carry parasympathetic fibres from the brainstem?

Answer 15

Oculomotor
Facial
Glossopharyngeal
Vagus

Question 16

Describe the route of parasympathetic innervation to head and neck

Answer 16

Arise from brainstem from (4) parasympathetic nuclei 
Hitch hike on one of 4 CNs 
Ganglia - 4 
Hitch hike on branches of CN V 
Target tissue

Question 17

What are some parasympathetic target tissues in the head and neck?

Answer 17

Smooth muscle in the iris - constrictor 
Ciliary muscle - lens
Lacrimal gland 
Mucosal glands in nasal/oral mucosa and respiratory tract 
Salivary glands

Question 18

Name the 4 parasympathetic nuclei

Answer 18

Edinger Westphal
Superior salivary
Inferior salivary
Dorsal motor

Question 19

Name the 4 parasympathetic ganglia

Answer 19

Ciliary
Submandibular
Pterygopalatine
Otic

Question 20

Describe the route of parasympathetic CN III

Answer 20

EWN
Hitch hike CN III
Ciliary ganglion
Hitch hike CN Va 
Eye 
- Ciliary body (lens)
- Constrictor of the pupil

Question 21

Which nuclei is involved in pupillary light reflexes?

Answer 21

Edinger westphal nuclei (left and right)

Question 22

Describe the pupillary light reflex

Answer 22

Light in left pupil
Sensory afferent from left retina CN II
Some branches leave CN II to enter midbrain
Connection with EDW nuclei - left and right
Parasympathetic fibres from EDW leave brainstem
Hitch hike on CN III (left and right)
Pass via ciliary ganglion
Reach sphincter pupillae

Question 23

What is the pupillary response in the contralateral eye called?

Answer 23

Consensual light reflex

Question 24

What do parasympathetic nerves associated with CN III innervate?

Answer 24

Sphincter pupillae

Question 25

Which two main branches of the facial nerve arise within the petrous bone?

Answer 25

Greater petrosal nerve | Chorda tympani nerve

Question 26

What parasympathetic ganglia are associated with parasympathetics associated with CN VII?

Answer 26

Pterygopalatine | Submandibular

Question 27

Describe the course of chorda tympani

Answer 27

Submandibular ganglion -> Hitch hikes on CN V -> Submandibular and sublingual salivary glands

Question 28

Describe the route of the greater petrosal nerve?

Answer 28

Pterygopalatine -> Hitch hikes on branches of CN V -> Lacrimal gland, nasal and oral mucosal glands

Question 29

What are some branches of CN IX?

Answer 29

Tympanic nerve - supplies sensory to middle ear | Lesser petrosal nerve

Question 30

Which ganglion is associated with parasympathetic CN IX?

Answer 30

Otic

Question 31

Where can the otic ganglion be found?

Answer 31

In infratemporal fossa

Question 32

What do post ganglionic parasympathetics of CN IX hitch hike on?

Answer 32

Branch of CN Vc

Question 33

What do parasympathetics of CN IX innervate?

Answer 33

Parotid gland

Question 34

Describe the parasympathetic route of CN IX

Answer 34

``` Preganglionic parasympathetics from brainstem with CN IX Jugular foramen Tympanic nerve Tympanic plexus Lesser petrosal nerve -> foramen ovale Otic ganglion Post ganglionic parasympathetics on CN Vc Parotid gland ```

Question 35

Describe the route of parasympathetic CN X

Answer 35

Medulla Hitch hikes on CN X Meets ganglion at or in target tissue Target

Question 36

What are the target tissues of parasympathetics of CN X?

Answer 36

Glands in laryngopharynx, larynx Glands and smooth muscle of oesophagus and trachea Heart Smooth muscle and glands within respiratory and GI tract

Question 37

What are the origins of parasympathetic NS in head and neck?

Answer 37

Brainstem

Question 38

Which nerves do parasympathetic of head and neck hitch hike on?

Answer 38

CN III, VII, IX, X

Question 39

How do post ganglionics of parasympathetic head and neck reach effector organs?

Answer 39

Branches of CN V | Except CN X

Question 40

Name the parasympathetic ganglia

Answer 40

Ciliary Pterygopalatine Submandibular Otic

Question 41

What are the effector tissues of parasympathetic NS in head and neck?

Answer 41

``` Eye (sphincter pupillae and ciliary muscles) Lacrimal glands Mucosal glands Salivary glands Parotid gland ```

Question 42

What are the parasympathetic responses in head and neck?

Answer 42

Constrict pupil Accommodation reflex - lens shape Glandular secretions - salivary and mucosal Cardiac muscle and smooth muscle in resp and digestive system

Question 43

What do parasympathetic fibres associated with CN IX innervate?

Answer 43

Parotid gland

Question 44

Post ganglionic parasympathetic fibres typically hitch hike with branches of the..

Answer 44

Trigeminal nerve