The brainstem Flashcards
The mamillary bodies are part of which system?
Limbic system
What causes the bulge in the floor of the 4th ventricle?
CN VII wrapping around the nucleus of CN VI
What are the 2 main arteries that supply the brain + brainstem?
Internal carotid arteries + Vertebral arteries
CN’s III + IV can be compressed by an aneurysm in which 2 arteries?
Superior cerebellar artery + Posterior cerebral artery
Which 2 arteries supply the midbrain?
Superior cerebellar artery
Posterior cerebral artery
Which artery supplies the pons?
Basilar artery w/ pontine branches
Which 3 arteries supply the medulla?
Anterior spinal artery
Vertebral arteries
Posterior inferior cerebellar artery (PICA)
Starting from medial to lateral, what is the arrangement of the 3 layers of nuclei in the brainstem?
Somatic motor
Visceral motor & visceral sensory
Somatic sensory
What is meant by branchial motor fibres?
Skeletal muscle derived from pharyngeal arches
What are the 4 somatic motor nuclei in the brainstem?
CN III - oculomotor nucleus
CN IV - trochlear nucleus
CN VI - abducens nucleus
CN XII - hypoglossal nucleus
What is the function of the oculomotor nucleus?
Motor to all eye muscles except lateral rectus and superior oblique
What is the function of the trochlear nucleus?
Motor to superior oblique muscle of the eye
What is the function of the abducens nucleus?
Motor to lateral rectus of the eye
What is the function of the hypoglossal nucleus?
Motor to the tongue
What are the 4 somatic sensory nuclei in the brainstem?
CN V - mesencephalic nucleus
CN V - principal nucleus
CN V - spinal nucleus
CN VIII - vestibulocochlear nucleus
What is the function of the mesencephalic nucleus?
Proprioception
What is the function of the principal nucleus?
Light touch
What is the function of the spinal nucleus?
Pain & temperature
Which 3 CN’s hitchhike on the spinal nucleus of CN V?
VII
IX
X
What are the 4 parasympathetic nuclei in the brainstem?
CN III - Edinger-Westphal nucleus
CN VII - superior salivatory nucleus
CN IX - inferior salivatory nucleus
CN X - dorsal vagal nucleus
What is the function of the Edinger-Westphal nucleus?
Pupillary light reflex
What is the function of the superior salivatory nucleus?
Parasympathetics to lacrimal glands + all salivary glands (except parotid)
What is the function of the inferior salivatory nucleus?
Parasympathetics to parotid gland
What are the 3 branchial motor nuclei in the brainstem?
CN V - trigeminal nucleus
CN VII - facial nucleus
CN IX, X, XI - nucleus ambiguus
What is the function of the trigeminal nucleus?
Branchial motor to muscles of mastication
What is the function of the facial nucleus?
Branchial motor to muscles of facial expression
What is the function of the nucleus ambiguus?
Branchial motor to pharynx, larynx, soft palate
What is the function of the dorsal vagal nucleus?
Autonomic control to body - heart, Gi tract, lungs
Which 4 structures would be knocked out with a block in the PICA?
Sensory nucleus (CN V)
Sympathetic nerves
Spinocerebellar tract
Spinothalamic tract
Which 4 structures would be knocked out with a block in the anterior spinal artery?
Motor nuclei
Medial longitudinal fasciculus
Medial lemniscus
Motor corticospinal
Is bulbar palsy a UMN or LMN lesion?
LMN
Is pseudobulbar palsy a UMN or LMN lesion?
UMN
Why is there a high likelihood that a pseudobulbar palsy will turn into a medical emergency?
Since it is an UMN lesion, spastic paralysis of the pharynx & larynx may develop = airway occlusion
Would damage to the Edinger-Westphal nucleus result in ipsilateral or contralateral loss of the pupillary light reflex?
Ipsilateral
Would damage to CN IV nucleus result in ipsilateral or contralateral loss of superior oblique function?
Contralateral
