Cranial Nerves Flashcards
What do the cranial nerves supply?
Somatic and visceral motor and sensory information to the head.
Which cranial nerves supply visceral sensory and motor innervation to the neck, chest and abdomen?
CNIX and CNX
Which cranial nerves are purely sensory?
CNI, II and VIII
Which cranial nerves are purely motor?
CNIII, IV, VI, XI and XII
Which cranial nerves are mixed sensory and motor?
CNV, VII, IX and X
Why do the mixed cranial nerves have multiple functions?
Because each cranial nerve contains many functional groups of fibres.
What are cranial nerves connected to centrally?
Cranial nerve nuclei
How are the cranial nerve nuclei organised?
Rostral to caudal roughly in order of the target tissues they are associated with, in columns of similar function.

Where are the motor nerve nuclei located in the brainstem?
In 3 columns close to the midline.

How are the 3 motor nerve nuclei columns arranged from medial to lateral?
Somatic, Branchial (gill) and visceral (autonomic)

Which structures are innervated by somatic motor nerves?
Extra-occular muscles and muscles of the tongue.
Which cranial nerves innervate the extra-occular muscles?
CNIII Occulomotor
CNIV Trochlear
CNVI Abducens
Which cranial nerve innervates the muscles of the tongue?
CNXII Hypoglossal
Which structures are innervated by branchial arch nerves?
Muscles of mastication
Muscles of facial expression
Muscles of pharynx and larynx
Which cranial nerve supplies the muscles of mastication?
Mandibular division of CNV (Trigeminal)

Which cranial nerve supplies the muscles of facial expression?
CN VII (Facial nerve)
Which cranial nerves supply the muscles of the pharynx and larynx?
CNIX (Glossopharyngeal nerve) and CNX (Vagus)
What is nucleus ambiguus?
Mostly a motor nucleus that lies behind the inferior olive.
It is the nucleus for CNIX (stylopharyngeus muscle) and CNX (levator palati muscle) that controls the pharynx and larynx.

What do the visceral efferents innervate?
Smooth muscles (autonomic)

Which nuclei comprise the visceral efferents?
CNIII - Edinger-Westfal nucleus
CNVII - Superior salivatory nucleus
CNIX - Inferior salivatory nucleus
CNX - Dorsal motor nucleus of the Vagus
Where are sensory nuclei located in the brainstem?
In 3 columns lateral to the medial 3 motor columns.

How are the 3 sensory nerve nuclei columns arranged from medial to lateral?
Visceral sensory
Somatic sensory
Special sensory

Which structures are innervated by the visceral afferent nerves?
Taste
Autonomic
Which cranial nerves are responsible for taste visceral afferents?
CNVII (Facial)
CNIX (Glossopharyngeal)
CNX (Vagus)

















