Neuro anatomy + physiology

Question 1

What cranial nerves originate from the cerebrum?

Answer 1

• olfactory nerve (CN I)
• optic nerve (CN II)

Question 2

What cranial nerves originate from the midbrain?

Answer 2

• trochlear nerve (IV)
• oculomotor (III)

Question 3

What cranial nerves originate from the pons?

Answer 3

• trigeminal (V)
• abducens VI
• facial VII
• vestibulocochlear VIII

Question 4

What cranial nerves originate from the medulla oblongata?

Answer 4

• glossopharyngeal IX
• vagus X
• accessory XI
• hypoglossal XII

Question 5

What is the function of of CNI?

Answer 5

• Sensory visceral
• Smell

Question 6

What is the function of CN II?

Answer 6

• Special somatic sensory (SSS) – senses derived from ectoderm (e.g. sight, sound, balance)
• Vision

Question 7

What is the function of CN III?

Answer 7

• Motor (somatic and visceral) : skeletal + smooth muscles
• Somatic muscles - 4 extrinsic eye muscles and levator palpebrae superioris.
• Visceral : pupillary sphincter

Question 8

What is the function of CN IV?

Answer 8

• Motor (somatic)
• Superior oblique

Question 9

What is the function of CN V?

Answer 9

• Ophthalmic (somatic sensory) -> Scalp, forehead and nose.
• Maxillary (somatic sensory) -> Cheeks, lower eye lid, nasal mucosa, upper lip, upper teeth and palate.
• Mandibular (Soamtic sensory + specific visceral motor/ smooth muscle):
  - GSS: anterior 2/3 tongue, skin over mandible and lower teeth.
  - SVM: muscles of mastication.

Question 10

What is the function of CN VI?

Answer 10

• general somatic motor -> Lateral rectus

Question 11

What is the function of CN VII?

Answer 11

GSS: sensation to part of ext. ear (General somatic sensory)

SVS: taste from ant. 2/3 tongue, hard and soft palate (Special visceral sensory)

SVM: muscles of facial expression. (Special visceral motor)

GVM: lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose. (General visceral motor)

Question 12

What is the function of CN VIII?

Answer 12

• Special somatic sensory (SSS)
• Hearing and balance

Question 13

What is the function of IX?

Answer 13

GSS: post. 1/3 tongue, ext. ear, and middle ear cavity.

GVS: carotid body and sinus.

SVS: taste from post. 1/3 tongue.

GVM: parotid gland.

SVM: stylopharyngeus

Question 14

What is the function of X?

Answer 14

GSS: ext. ear, larynx and pharynx.

GVS: larynx, pharynx and, thoracic & abdominal viscera.

SVS: taste from epiglottis region of tongue

GVM: smooth muscles of pharynx, larynx and most of the GIT.

SVM: most muscles of pharynx and larynx.

Question 15

What is the function of CN XI?

Answer 15

• Motor
• GSM: trapezius and sternocleidomastoid.
• SVM: a few fibres run with CNX to viscera.

Question 16

What is the function of CN XII?

Answer 16

• Motor GSM
• Intrinsic and extrinsic tongue muscles (except the palatoglossus).

Question 17

What is the function of the hypothalamus?

Answer 17

• Haemostasis
• Hormonal regulation

Question 18

What is the function of the thalamus?

Answer 18

• Relay sensory and motor signals
• Regulation of consciousness and alertness

Question 19

What is the function of the amygdala?

Answer 19

• Emotional centre
• Fight or flight reactions
• Modulation of memory

Question 20

What is the function of the hippocampus?

Answer 20

Memory conversion

Question 21

What is the function of the frontal lobe?

Answer 21

Decision making, problem solving , planning. Higher intellect, personality, mood, social conduct and language (dominant hemisphere side only).

Question 22

What is the function of the parietal lobe?

Answer 22

Perception, recognising objects, visuospatial processing, recognising numbers. Recognition of sensations and processing sensory information of multiple modalities

Question 23

What is the function of the temporal lobe?

Answer 23

Learning, emotion, memory, language + hearing

Question 24

What is the function of the occipital lobe?

Answer 24

visual perception + association

Question 25

What is the role of the pons?

Answer 25

• largest part of the brainstem, function as a connection between the cerebrum and cerebellum
• Controls respiration, sleeping, bladder, taste & hearing.

Question 26

What is the role of the midbrain?

Answer 26

It acts as a conduit between the forebrain above and the pons and cerebellum below.

Question 27

What is the role of the medulla?

Answer 27

Houses essential ascending and descending nerve tracts as well as brainstem nuclei. Contains reflex centers of vomiting, coughing, sneezing and swallowing.

Controls autonomic NS. Also contains respiration, cardio & vomiting centres

Question 28

What is the role of the caudate nucleus?

Answer 28

• Memory
• Learning

Question 29

What is the role of the lentiform nucleus?

Answer 29

• Putamen and the Globus Pallidus
• Putamen linked to substantia nigra → role in degenerative neurological disorders
• Putamen functions → Regulating movements + learning
• Globus pallidus → subconscious regulation of movement

Question 30

What is the function of the thalamus?

Answer 30

• pathway from cerebral cortex + midbrain (brainstem)
• Functions:
  
  • regulation of sleep, wakefulness, the level of awareness, activity,
  • processing and relaying sensory information to various parts of the cerebral cortex

Question 31

What is the flow of CSF in the ventricles?

Answer 31

• Ependymal cells ⇒ Choroid plexus in Lateral Ventricles
• Intraventricular Foramen (foramen of Monroe) ⇒ Third Ventricle
• Cerebral Aqueduct ⇒ Fourth Ventricle
• Leaves Lateral and Medially through Foramen of Luschka & Magendie ⇒ Subarachnoid Space
• Around brain ⇒ down spine ⇒ reabsorbed into dural venous sinuses from Arachnoid granulations
• All drains in internal jugular vein