PBL 1

Question 1

what are the 2 functions of the meninges?

Answer 1

to provide a supportive framework for the cerebral and cranial vasculature
to act with the CSF to protect the CNS from mechanical damage

Question 2

what are the 2 connective tissue layers of the dura matter?

Answer 2

endosteal layer (lines inner surface of bone of cranium)
meningeal layer (lines endosteal layer)

Question 3

where are the dorsal sinuses found?

Answer 3

between the endosteal and meningeal layers of the dura matter

Question 4

what are venous sinuses responsible for?

Answer 4

Venous vasculature of the cranium, draining into the internal jugular veins.

Question 5

what are arachnoid granulations?

Answer 5

structures filled with CSF that extend into the venous sinuses through openings in the dura mater and allow the drainage of CSF from subarachnoid space into venous system

Question 6

what are the 3 layers of the meninges from superficial to deep?

Answer 6

dura mater, arachnoid mater, pia mater

Question 7

what are the 2 groups of bones of the skull?

Answer 7

cranial bones and facial bones

Question 8

what makes up the cranial bones?

Answer 8

frontal bone, parietal bone, temporal bone, occipital bone, sphenoid bone, ethmoid bone

Question 9

in which bone is the foramen magnum found?

Answer 9

at the base of the occipital bone

Question 10

what are the layers of the scalp?

Answer 10

skin, connective tissue, epicranial aponeurosis, loose areolar connective tissue and periosteum

Question 11

where does the epicranial aponeurosis run from and to?

Answer 11

from the frontal muscle to the occipitalis

Question 12

what is the function of the periosteum?

Answer 12

to provide nutrition to the bone and the capacity for repair

Question 13

what are the 2 main arteries that supply blood to the brain?

Answer 13

internal carotid artery and vertebral arteries

Question 14

what is the function of the circle of Willis?

Answer 14

to provide collateral blood flow between the anterior and posterior circulations of the brain, protecting against ischemia in the event of vessel disease or damage in one or more areas

Question 15

describe the path of the internal carotid artery?

Answer 15

They originate at the bifurcation of the left and right common carotid arteries, at the level C4.
They move superiorly within the carotid sheath, and enter the brain via the carotid canal of the temporal bone.
Once in the cranial cavity, the internal carotids pass anteriorly through the cavernous sinus

Question 16

what does the internal carotid artery give rise to?

Answer 16

ophthalmic artery
posterior communicating artery
middle cerebral artery
anterior choroidal artery
anterior cerebral artery

Question 17

describe the cerebral venous drainage?

Answer 17

The cerebral veins empty into the dural venous sinuses situated within the subarachnoid space.

Question 18

what do the superficial veins of the cerebrum drain into?

Answer 18

superior sagittal sinus

Question 19

what do the deep veins of the cerebrum drain into?

Answer 19

transverse, straight and sigmoid sinuses

Question 20

outline the pathology of subdural bleeds

Answer 20

usually a tear of cerebral veins occurs causing blood to escape from the blood vessel and form a blood clot/haematoma that puts pressure on the brain and damages it

Question 21

what are the common causes of subdural bleeds?

Answer 21

RTCs, brain atrophy in elderly patients and alcoholics, assault

Question 22

how do subdural bleeds present?

Answer 22

headache, feeling/being sick, confusion, personality changes, feeling drowsy, loss of consciousness

Question 23

how are acute and chronic subdural bleeds different?

Answer 23

acute- symptoms start very soon after sever head injury

chronic- few days or weeks later symptoms begin to occur

Question 24

what are the 2 most widely used surgical techniques for subdural bleeds?

Answer 24

craniotomy

burr holes

Question 25

what is a craniotomy?

Answer 25

a section of the skull is temporarily removed so the surgeon can access and remove the haematoma

Question 26

what is a burr hole?

Answer 26

a small hole is drilled into the skull and a tube is inserted through the hole to help drain the haematoma

Question 27

where is the primary somatosensory cortex?

Answer 27

across the central sulcus and behind the primary motor cortex

Question 28

what is the function of the primary somatosensory cortex?

Answer 28

Receives nerve impulses for touch, pressure, itch, tickle, temperature, pain, and proprioception, and is involved in the perception of these somatic sensations.

Question 29

which Brodmann's areas are the primary somatosensory cortex?

Answer 29

1,2 and 3

Question 30

which brodmann's area is the primary gustatory area?

Answer 30

43

Question 31

what is the function of the primary gustatory area?

Answer 31

Receives impulses for taste and is involved in gustatory perception and taste discrimination

Question 32

which brodmanns area is the olfactory cortex?

Answer 32

28

Question 33

where is the olfactory cortex located?

Answer 33

in the uncus, found along the ventral surface of the temporal love

Question 34

what is the function of the olfactory cortex?

Answer 34

Receives impulses for smell and is involved in olfactory perception

Question 35

where is the visual area located?

Answer 35

on the calcimine sulcus deep within the inside folds of the occipital lobe

Question 36

what brodmanns area is the visual area?

Answer 36

17

Question 37

what is the function of the visual area?

Answer 37

Receives visual information and is involved in visual perception.

Question 38

where is the primary auditory cortex located?

Answer 38

on the transverse gyrus that lie on the back of the superior temporal convolution of the temporal lobes

Question 39

what brodmanns area is the primary auditory cortex?

Answer 39

41 and 42

Question 40

what is the function of the primary auditory cortex?

Answer 40

Receives information for sound and is involved in auditory perception

Question 41

what are the 3 areas of the motor cortex?

Answer 41

the primary motor cortex, premotor cortex and supplementary motor area

Question 42

which brodmanns area is the primary motor cortex?

Answer 42

4

Question 43

what is the function of the primary motor cortex?

Answer 43

the main contributor to the generation of neural impulses that control execution of movement

Question 44

where is the premotor cortex located?

Answer 44

anterior to the primary motor cortex

Question 45

what is the function of the premotor cortex?

Answer 45

responsible for some aspects of motor control

Question 46

what are the functions of the supplementary motor areas?

Answer 46

internally generated planning of movement, planning of sequences of movement, and the coordination of the two sides of the body.

Question 47

where is the supplementary motor area located?

Answer 47

on the midline surface of the hemisphere anterior to the primary motor cortex

Question 48

what do association areas do?

Answer 48

integrate information from different receptors or sensory areas and relate the information to past experiences. Then the brain makes a decision and sends nerve impulses to the motor areas to generate responses

Question 49

what is the prefrontal association complex?

Answer 49

A region of the brain located in the frontal lobe that is involved in planning actions and movement, as well as abstract thought.

Question 50

what is the wernickes area?

Answer 50

The posterior section of the superior temporal gyrus in the dominant cerebral hemisphere, one of two parts of the cerebral cortex linked with speech

Question 51

what is the brocas area?

Answer 51

A region in the frontal lobe of the dominant hemisphere (usually the left) of the hominid brain with functions linked to speech production

Question 52

left untreated, what can raised inter cranial pressure cause?

Answer 52

brain injury, seizure, coma, stroke, or death.

Question 53

why do we get raised intercranial pressure?

Answer 53

The cranium andthe relatively inelastic dura, form a rigid container, such that the increase in any of its contents (brain, blood, or CSF) will tend to increase the ICP.

Question 54

what are common symptoms of raised inter cranial pressure?

Answer 54

headache, vomiting without nausea, ocular palsies, altered level of consciousness, back pain, and papilledema.

Question 55

if the raised inter cranial pressure causes a displacement of brain tissue, what additional symptoms can you get?

Answer 55

pupillary dilatation, abducens palsies, and the Cushing’s triad

Question 56

what is the cushings triad?

Answer 56

bradycardia , irregular respirations, and a widened pulse pressure.