Cranial Nerves Flashcards
How many cranial nerves are there?
12
What are common causes of nerve compression?
Inflammation
Tumours
and Fraction
What do somatic motor fibres supply?
Supple striated muscle
Are somatic motor fibres voluntary or involuntary?
Voluntary
What do autonomic motor fibres supply?
The things we dont think about
e.g smooth muscle
What are visceral sensory nerves?
Receive inputs from afferent sources e.g pharynx, heart, lungs
We are not normally conscious of it
Where do inputs from general sensory nerves come from?
Afferent inputs
e.g touch temp pain
From skin and mucous membrane
What are the inputs for special sensory nerves?
Taste, hearing, smelling, vision and balance
Do somatic motor fibres synapse?
No
Do autonomic motor fibres synapse?
Yes
What is CN I?
Olfactory neve
What is CN II?
Optic nerve
What is CN III?
Oculomotor nerve
What is CN IV?
Trochlear
What is CN V?
Trigeminal Nerve
What is CN VI?
Abducent nerve
What is CN VII?
Facial nerve
What is CN VIII?
Vestibulocohlear nerve
What is CN IX?
Glossopharyngeal nerve
What is CN X?
Vagus nerve
What is CN XI?
Accessory nerve
What is CN XII?
Hypoglossal nerve
What is the main function of CN I?
Sensory smell
What is the main function of CN II?
Sensory vision
What is the main function of CN III?
Motor (eye movement)
What is the main function of CN IV?
Motor (eye movement)
What is the function of CN V?
Mixed sensation
Muscles of facial expression, parasympathetic, taste
What is the function of CN VI?
Motor (eye movement)
What is the function of CN VII?
Mixed
Muscles of facial expression, parasympathetic, taste
What is the function of CN VIII?
Sensory (hearing and balance)
What is the function of CN IX?
Mixed
Swallowing, sensation from tongue
Parasympathetic supply
What is the function of CN X?
Mixed
Muscles of throat
What is the function of CN XI?
Motor
Soft palate, throat and neck
What is the function of CN XII?
Motor (tongue)
What is the pathway of CN I?
Receptors in olfactory epithelium of nasal cavity
Olfactory nerve fibres pass through foraminfera in cribriform plate
Enter olfactory bulb in anterior cranial fossa
What can a fracture cribriform plate cause?
Anosmia due to tearing of the olfactory nerve
What is the pathway of CN II?
Enters via optic canal
nerve join to form optic chiasma
Fibres from medial half of each retina cross to form optic tract