Lecture 3: Brain

Question 0

Dural Innervation branches of trigeminal nerve

Answer 0

Branches of trigeminal nerve
CN V1 => anterior & posterior flax cerebrii+ tentorium cerebelli
CN V2 => anterolateral reflections.
CN V3 => lateral reflections.

Floor of posterior cranial fossa by: C2, C3, hypoglossal and vagus

Question 1

Dural Innervation

Answer 1

Only meningeal layer to be in innervated by sensory fibres
Innervated by:
- trigeminal
- vagus
- upper cervicals
Also stretch sensitive– causes head aches

Question 2

Dura mater supplied by which artery?

Answer 2

Middle meningeal artery

Question 3

Where does dura mater drain to?

Answer 3

Internal jugular vein

Question 4

Arachnoid mater

Answer 4

Located between dura and pia mater
Is avascular
Not attached to the dura
Subarachnoid space between arachnoid and pia mater is filled with CSF
Folds of arachnoid mater project into venous sinus to form arachnoid villi (granulations)
Arachnoid granulations is where CSF diffuses into the blood stream

Question 5

Pia mater

Answer 5

Highly vascularised, extremely thin

Question 6

Hippocampus

Answer 6

Plays a role in behaviour and emotional expression as well as a key role in memory and learning

Question 7

Thalamus

Answer 7

Receives and processes pre cortical input from all sensory systems EXCEPT olfactory

Question 8

Hypothalamus

Answer 8

Located lateral to third ventricle

Question 9

Mammillary bodies

Answer 9

Connected to the hippocampus via the fornix

Projects into the anterior nucleus of the thalamusn

Question 10

Medial geniculate body

Answer 10

MEDIAL GENICULATE body relays AUDITORY impulses from INFERIOR COLLICULUS to primary auditory cortex.

Question 11

Lateral geniculate body

Answer 11

LATERAL GENICULATE body relays VISUAL impulses from optic tract to primary visual cortex.

Question 12

Disturbances of PCA

Answer 12

Occlusion will lead to visual disturbances

Question 13

Disturbances of MCA

Answer 13

Occlusion will lead to sensorimotor function loss in hands and face

Question 14

Disturbances of ACA

Answer 14

Occlusion will lead to sensorimotor function loss in e lower limbs and bladder weakness

Question 15

Ventricles lined with what type of cells?

Answer 15

ependymal cells

Question 16

ependymal cells forming the choroid plexuses that produce and secrete?

Answer 16

cerebrospinal fluid (CSF).

Question 17

Cerebrospinal fluid does what?

Answer 17

CSF removes waste products associated with neuronal activity & gives brain buoyancy to protect it from trauma.

Question 18

Dural venous sinuses

Answer 18

• Between periosteal and meningeal layers of dura. No valves.
• Contains blood from superficial brain veins.
• Drains to Internal Jugular Vein.

Question 19

Two layers of dural mater?

Answer 19

• Two layers: periosteal and meningeal layers.

• periosteal = periosteum covering inner surface of calvaria.
Does not extend through foramen magnum.

Question 20

Arteries of cerebrum

Answer 20

• Anterior cerebral artery (branch of internal carotid artery)
• Middle cerebral artery (branch of internal carotid artery)
• Posterior cerebral artery (terminal branch of basilar artery)

Question 20

Common site of atherosclerotic narrowing?

Answer 20

Bifurcation of common carotid artery

Question 20

Internal carotid and vertebral arteries do what kind of circulation?

Answer 20

Internal carotid- anterior circulation

Vertebral arteries- posterior circulation

Question 20

Post-central gyrus (dark blue) =

Answer 20

primary somatosensory cortex
Nerve cells in this area receive and interpret sensations of pain,
temperature, touch and pressure from contralateral side of body.

Question 20

Pre-central gyrus (dark pink) =

Answer 20

primary motor cortex.

Large motor nerve cells in this area control voluntary movements 
on opposite (contralateral)  side of body.

Question 20

Corpus callosum?

Answer 20

commissure between cerebral hemispheres

Question 20

Septum pellucidum?

Answer 20

stretches between the two to form medial wall of lateral ventricles

Question 20

What are Gyri?

Answer 20

elevated ridges

Question 20

What are Sulci?

Answer 20

shallow grooves

Question 20

What are Fissures?

Answer 20

deep grooves

Question 20

Fourth ventricle has foramina in it’s roof so CSF can escape into the?

Answer 20

subarachnoid space

Question 20

Choroid plexus is located where?

Answer 20

Lateral ventricle