6. Autonomic Innervation Of Head And Neck Flashcards
What is the autonomic nervous system part of?
Peripheral nervous system
Where is the central control of the autonomic nervous system from?
Hypothalamus
What does the autonomic nervous system maintain?
Maintains and fine tunes internal environment
What makes up the autonomic nervous system?
Sympathetic and parasympathetic nervous systems
What are the target tissues of ANS?
Smooth muscle
Cardiac muscle
Glands (lacrimal, mucosal, salivary)
What does sympathetic nervous system do?
Smooth muscle of blood vessels, eye lid and iris (dilator pupillae)
Sweat glands
Arrector pili muscles
Decreases secretions from salivary and lacrimal glands
What does the parasympathetic nervous system do?
Smooth muscle of iris (sphincter pupillae) and muscle in ciliary body (controls thickness of lens)
Lacrimal glands
Salivary and mucosal glands
Smooth muscle of respiratory and GI
What is the thoracolumbar outflow?
Sympathetic exits of CNS
Segments T1-L2 of spinal cord
Cells bodies within lateral horn of grey matter of spinal cord
What is the craniosacral outflow?
Exit of parasympathetic from CNS
Cranial - 4 cranial nerves
Sacral - S2-S4 (pelvic splanchnics)
How would the pupil differ in a Horner’s syndrome compared to an oculomotor nerve lesion?
Horner’s syndrome - miosis (constricted pupil)
CNIII lesion - mydriasis (dilated pupil)
What happens in Horner’s syndrome?
Miosis
Ptosis
Anhydrosis
What causes Horner’s syndrome?
Pathology involving apex of lung and/or common carotid artery and its branches can damage the sympathetic trunk carrying the nerves that supply the eye and face, causing autonomic dysfunction
Which cranial nerves carry parasympathetic fibres from the brainstem?
Oculomotor
Facial
Glossopharyngeal
Vagus
What is the route of the parasympathetic fibres of cranial nerves?
Arise from brainstem from parasympathetic nuclei Hitch hike onto one of 4 CNs Parasympathetic ganglia Hitch hike on to branches of CNV Target tissues
What are the 4 parasympathetic nuclei?
Edinger westphal
Superior salivary
Inferior salivary
Dorsal motor