Organisation of brainstem and cranial nerves Flashcards
What makes up the brainstem
Part of the CNS between the cerebrum and spinal cord (-cerebellum)
Midbrain
Pons
Medulla oblongata
What are the roles of the colliculi and where are they found
Found on the posterior surface of the brainstem
superior - coordinated neck and eye movement
Inferior colliculus - auditory reflexes
Which cranial nerve emerges from the back brainstem
IV, trochlear nerve
Where is the 4th ventricle
Posterior surface of the pons (floor)
What is found on the posterior surface of the medullla
Dorsal columns
What is found immediately below the optic chiasm
Pituitary stalk
What forms the base of the hypothalamus
Mammillary bodies
What is the role of the trigeminal nerve and where does it emerge
Completely from the lateral part of the pons
touch sensation throughout head and neck + motor function
Which cranial nerves emerge from the medulla and what are their roles
Abducens - eye
Facial - face
Vestibulocochlear - balance and hearing
What are the roles of the glossopharyngeal, vagus and accessory nerves
Glossopharyngeal – tongue, swallowing, pharynx, mastication
Vagus - parasympathetic autonomic output
Accessory – shoulder muscles and sternocleidomastoid
What is the role of the hypoglossal nerve
tongue – all tongue muscles
What is the cerebral penduncle
Corticospinal tract that emerges as the pyramidal decussation
What are the cranial nerves that emerge form the anterior surface of the brainstem
Optic chiasm Oculomotor Trigeminal Glossopharyngeal Vagus Accessory Hypoglossal Abducens Facial Vestibulocochlear
What are the functional classifications for afferent nerves
General somatic afferent (GSA) - sensation from skin and mucous membranes
General visceral afferent (GVA) - sensation from GI tract, heart, vessels & lungs
Special somatic afferent - vision, hearing & equilibrium
Special visceral afferent - smell & taste
What are the functional classifications for efferent nerves
General somatic efferent (GSE) - muscles for eye & tongue movements
General visceral efferent (GVE) - preganglionic parasympathetic
Special visceral efferent
muscles involved in chewing, facial expression, swallowing, vocal sounds & turning head
Which nuclei emerge as GSE nerves
Oculomotor
Trochlear
Abducens
Hypoglossal
Which nuclei emerge as SVE nerves
Trigeminal
Facial
Ambiguus
Accessory
Which nuclei emerge as GVE nerves
Edinger westphal
Salivatory
Salivatory, vagus
Which nuclei emerge as SSA nerves
Vestibulocochlear
Which nuclei emerge as GSA nerves
Trigeminal
Which nuclei emerge as GVA/SVA nerves
Solitarius
What are the distinguishing features of the midbrain
Looks like Mickey Mouse Cerebral aqueduct (only present here) Substantia nigra Cerebral peduncle (ears of mm) Inferior colliculus
What are the distinguishing features of the pons
Transverse fibres
4th ventricle (floor)
Middle cerebellar peduncle (where the pons connects to the cerebellum)
What are the distinguishing features of the medulla
Pyramids
Inferior olivary nucleus (distinctive wavy shape)
What are the distinguishing features of the lower medulla
Start of the central canal of the spinal cord
Dorsal columns
Pyramidal decussation (fibres crossing over)
What occurs in lateral medullary syndrome
Thrombosis of vertebral artery or Posterior inferior cerebellar artery
What are the symptoms of lateral medullary syndrome
Vertigo
Ipsilateral cerebellar ataxia
Ipsilateral loss of pain/thermal sense (face)
Horner’s syndrome
Hoarseness, difficulty in swallowing
Contralateral loss of pain/thermal sense (trunk and limbs)
Which cranial nerves are involved in lateral medullary syndrome and which symptoms do they produce
Vestibular - vertigo
Inferior cerebellar peduncle - ataxia
Spinal nerve (trigeminal) - loss of pain/thermal sense
N Ambiguus - hoarseness and difficulty swallowing
Spinothalamic tract - contralateral loss of pain
Sympathetic tract - Horner’s
Where are the nuclei for the oculomotor nerve and what is its functional classification
Midbrain as GSE
Where are the nuclei for the Trochlear nerve and what is its functional classification
Midbrain as GSE
Where are the nuclei for the Trigeminal nerve and what is its functional classification
Midbrain, Pons, medulla and cervical spinal cord as GSA
Pons as SVE
Where are the nuclei for the Abducens nerve and what is its functional classification
Pons as GSE
Where are the nuclei for the Facial nerve and what is its functional classification
Pons as SVE
Where are the nuclei for the Vestibulocochlear nerve and what is its functional classification
Pons and Medulla as SSA
Where are the nuclei for the Vagus nerve and what is its functional classification
Medulla as GVE
Where are the nuclei for the Accessory nerve and what is its functional classification
Cervical spinal cord as SVE
Where are the nuclei for the Hypoglossal nerve and what is its functional classification
Medulla as GSE
