Week 2 content

Question 1

what are major gyrus and sulci in the brain

Answer 1

Sulci - longitudinal fissure, central sulcus and lateral sulcus of the fissure, calcarine sulcus.

gyri - precentral gyrus, post central gyrus.

Question 2

list the specialized cortical regions

Answer 2

primary motor cortex (pre-central gyrus)
primary somatosensory cortex (post-central gyrus)
primary auditory gyrus (temporal lobe)
primary visual cortex (occipital lobe)

wernickes area

Question 3

what are the three classifications of white matter in the cerebrum

Answer 3

projection fibres
commissural fibres
association fibres

Question 4

define projection fibres

Answer 4

→ Sensory of motor fibres travelling to connect the brain with the brainstem and the spinal cord.
→ Projection fibres can either be ascending or descending along the spinal cord.

Question 5

commissural fibres

Answer 5

→ Connects corresponding regions of the two hemispheres.

Question 6

association fibers

Answer 6

→ Connects areas within one hemisphere.
→ There are both short and long association fibres.

Question 7

what is the diecephalon

Answer 7

→ Located – just above the brainstem, between the cerebral hemispheres, it has the third ventricle between its left and right sides. It has an internal capsule lying superficial to it – the diencephalon is a very deep structure.
→ It is divided into the epithalamus, thalamus, subthalamus, hypothalamus.

Question 8

thalamus

Answer 8

Thalamus
→ Largest most dorsal nuclear mass
→ Shape of 2 small eggs stuck together. There is a 3rd ventricle in the centre, and an internal capsule at the lateral aspect.
→ Has many connections to the lobes and functional areas of the brain.
o Sensory part of thalamus – ventral posterior lateral and medial.
o Motor part of thalamus – ventral lateral and internal capsule at lateral aspect.
→ Relay centre.

Question 9

hypothalamus

Answer 9

Hypothalamus (hypo meaning “under/lower than”)
→ Ventral and rostral to thalamus
→ Regulation of autonomic/endocrine functions (pituitary gland, mamillary bodies, optic chiasm).

Question 10

subthalamus

Answer 10

Subthalamus (sub meaning “below than”)
→ Immediately ventral to the thalamus, located at the function of the diencephalon and brainstem.
→ Related to the basal ganglia for movement control (sub-thalamic nuclei).

Question 11

epithalamus

Answer 11

Epithalamus (epi meaning “outside/on top of”)
→ Caudal to the thalamus
→ Circadian rhythm and sexual reproduction cycles.

Question 12

cranial nerve I

Answer 12

olfactory nerve
originates from the cerebrum, purely sensory fibers, has autonomic fibers, innervates the olfactory epithelium via the olfactory bulb, responsible for olfaction (smell).

Question 13

cranial nerve II

Answer 13

oculomotor nerve, originates from the cerebrum, purely sensory, has autonomic fibers, innervates the retina, responsible for visual sensory information.

Question 14

cranial nerve III

Answer 14

oculomotor nerve, originates from the midbrain, purely motor, has autonomic fibers, innervates the superior, inferior and medial recti, inferior olblique levator and levator palpebare superioris (4/6 eye muscles), responsible for eye motor control.

Question 15

cranial nerve IV

Answer 15

trochlear nerve, originates from the posterior brainstem, purely motor, has autonomic fibers, innervates the superior oblique muscle, and is responsible for eye motor control.

Question 16

cranial nerve V

Answer 16

trigeminal nerve, originates from the pons, is a mixed nerve (sensory and motor), has autonomic fibers, innervates the face, scalp, cornea, nasal and oral cavities, also the temporalis, lateral and medial pterygoids, masseter.

responsible for general sensation, opening and closing mouth, movement of the eyeball, taste, facial movement as well as salivation and lacrimation.

Question 17

cranial nerve VI

Answer 17

abducens nerve, originates from the pons, purely motor, innervates the lateral rectus muscle, responsible for movement of the eyeball.

autonomic fibers??

Question 18

cranial nerve VII

Answer 18

facial nerve, originates from the pons, mixed (motor and sensory), has autonomic fibers, innervates the anterior two thirds or the tongue, muscle of facial expression, responsible for taste, facial movement.

Question 19

cranial nerve VIII

Answer 19

vestibulocochlear nerve, originates from between pons and medulla, purely sensory, innervates the vestibular apparatus, responsible for vestibular sensation, balance and pathway to auditory input.

autonomic fibers??

Question 20

cranial nerve XI

Answer 20

glossopharyngeal nerve, originates from the medulla, purely sensory, has autonomic fibers, innervates the stylopharyngeus muscle.

responsible for the general sensation and taste, swallowing and salivation.

Question 21

cranial nerve X

Answer 21

vagus nerve, originates from the medulla, mixed (motor and sensory), has autonomic fibers, innervates pharynx, larynx, oesophagus, and thoracic and abdominal viscera.

responsible for swallowing, speech, general sensation, control of cardiorespiratory system and gastrointestinal system.

Question 22

cranial nerve XI

Answer 22

accessory nerve, branches from the vagus nerve, motor nerve, no autonomic fibers, sternomastoid and teapezius muscles.

responsible for the head and the shoulder.