The Brain

Question 1

what are the gyri and sulci of the brain?

Answer 1

gyrus = lump
sulci = groove

Question 2

what is the central sulcus and what are on each side?

Answer 2

sulcus in the middle of the brain, runs from medial to lateral
motor cortex (pre-central gyrus) anteriorly
sensory cortex (post-central gyrus) posteriorly

Question 3

where is the lateral fissure and what does it contain?

Answer 3

between the temporal and parietal lobes

contains the middle cerebral artery

Question 4

where is the longitudinal fissure and what does it contain?

Answer 4

sulcus through the midline of the brain, dividing the hemispheres
contains the anterior cerebral arteries

Question 5

what is the corpus callosum?

Answer 5

white matter tracts that connect the cerebral hemispheres

Question 6

where are association tracts found?

Answer 6

between gyri of the same hemisphere

Question 7

where do commissural tracts/fibres run?

Answer 7

from one hemisphere to the corresponding region of the other hemisphere

Question 8

where do the projection fibres arise from?

Answer 8

cerebrum to thalamus, brainstem etc.

Question 9

what is the function of basal ganglia?

Answer 9

regulate initiation and termination of body moments, also thought to be involved with memory, planning and emotional response (via limbic system)

Question 10

what forms the lentiform nucleus?

Answer 10

globus palladus and putamen

Question 11

what does the substansia nigra in the mid-brain communicate with and what is its role?

Answer 11

caudate and putamen

control sub-conscious muscle action

Question 12

what does the sub-thalamic nuclei communicate with?

Answer 12

the globus palladus

Question 13

what does the diencephalon contain?

Answer 13

thalamus
hypothalamus
pineal gland

Question 14

what is the role of the thalamus?

Answer 14

sensory relay station involved in motor pathways with connections to the hypothalamus and limbic systems

Question 15

what is the role of the hypothalamus?

Answer 15

regulates ANS and homeostasis and produces hormones

Question 16

what is the role of the pineal gland?

Answer 16

produces melatonin to regulate body clock

it’s epithelium contians the habenular nucleus whihc is responsible for olfaction and emotional response

Question 17

what cranial nerves originate in the midbrain?

Answer 17

III and IV (oculomotor and trochlear)

Question 18

what does the midbrain connect?

Answer 18

pons and medulla to diencephalon

Question 19

where is the superior colliculi and what is its role?

Answer 19

in the midbrain

visula tracking, scanning

Question 20

where is the inferior colliculi and what is its role?

Answer 20

in the midbrain

auditory startle reflex

Question 21

where are red nuclei and what is it’s role?

Answer 21

in the midbrain

co-ordinate muscle movement

Question 22

what cranial nerves originate in the pons?

Answer 22

V, VI, VII and vestibular part of VIII (trigeminal, abducens, facial and part of vestibulocohlear)

Question 23

what does the pons contain and what are their roles?

Answer 23

pontine nuclei: coordination and maximising voluntary motor output
tracts e.g. pneumotaxic: helps control breathing

Question 24

what cranial nerves originate in the medulla?

Answer 24

IX, X, XI, XII (glossopharyngeal, vagus, spinal accessory and hypoglossal)

Question 25

what does the medulla contain and what are their roles?

Answer 25

pyramids (motor tracts) cardiovascular centres (rate/force of heartbeat and diameter of vessels) breathing centres nuclei concerned with touch, pressure and vibration

Question 26

what is the role of the olives in the medulla?

Answer 26

proprioception (joint and muscle position)

Question 27

what divides the cerebellum into lobes?

Answer 27

cerebral vermis

Question 28

what is the role of the cerebellum?

Answer 28

controls sub-conscious aspects of skeletal muscle movements and coordinates complex sequences regulates posture and balance

Question 29

what do the superior, middle and inferior peduncles connect?

Answer 29

superior: midbrain to cerebellum middle: pons to cerebellum inferior: medulla to cerebellum

Question 30

what does the pituitary gland release?

Answer 30

``` growth hormone (GH) follicle stimulating hormone (FSH) luteinising hormone (LH) ```

Question 31

what is the circle of willis and what is it formed from?

Answer 31

``` is a circulatory anastomosis that supplies blood to the brain and surrounding structures formed from: - anterior communicating - L+R anterior cerebral - L+R internal carotid - L+R posterior cerebral - L+R posterior communicating note: middle cerebral, basilar and vertebral arteries also supply the brain but aren't part of the circle ```

Question 32

what does the middle cerebral artery supply?

Answer 32

temporal loves

Question 33

what does the posterior cerebral artery supply?

Answer 33

occipital lobe and base of brain

Question 34

what are the branches of the basilar artery?

Answer 34

cerebellar, pontine and medullary arteries

Question 35

what does the anterior cerebral artery supply?

Answer 35

frontal and parietal lobes

Question 36

where do the vertebral arteries arise from?

Answer 36

the subclavian

Question 37

what are the layers of the meninges surrounding the spinal cord?

Answer 37

pia mater: innermost layer arachnoid mater: middle layer, fine 'spiderweb' of CT dura mater: outermost layer, tough CT sheath

Question 38

what is the space between the pia and arachnoid mater and what does it contain?

Answer 38

subarachnoid space | contains cerebrospinal fluid

Question 39

what lines the skull, what is its role and what does it form?

Answer 39

dura mater protects the brain forms the dural venous sinuses

Question 40

what covers the surface of the brain and what does it carry?

Answer 40

arachnoid mater | carries blood vessels

Question 41

what is the covering of the brain beneath the arachnoid mater?

Answer 41

pia mater | adheres to surface, goes into the sulci and around the gyri

Question 42

what does the anterior meningeal artery arise from and what does it supply?

Answer 42

ethmoid branches of the internal carotid | supplies the dura of the anterior fossa

Question 43

what does the middle meningeal artery arise from, what does it pass through and what does it supply?

Answer 43

from maxillary artery passes through the foramen spinosum supplies the dura with blood (major vessel supplying it, if damaged causes extra-dural haematoma)

Question 44

what does the posterior meningeal artery arise from and what does it supply?

Answer 44

from occipital artery | supplies dura of posterior fossa

Question 45

what nerves supply the dura?

Answer 45

anterior and posterior ethmoidal nerve anterior meningeal branches of ethmoidal nerve (CN V1) meningeal branch of maxillary (CN V2) meningeal branches of mandibular (CN V3) tentorial nerve (recurrent meningeal branch of opthalmic, CN V1) fibres from C2+3, some of which are distributed by CN X

Question 46

what is the role of the dural venous sinuses and what are they found between?

Answer 46

drain blood from the brain and channel it into the IJV between either the periosteum and dura (e.g. sigmoid sinus) or between two of the layers of dura (e.g. inferior sagittal sinus)

Question 47

what are the names of the four ventricles of the brain and where are they found?

Answer 47

``` lateral ventricles x2 (one in each hemisphere) 3rd ventricle (inside the thalamus) 4th ventricle (in the pons or upper part of medulla) ```

Question 48

how does the third ventricle connect to the lateral ventricles?

Answer 48

inter-ventricular foramina of Monro

Question 49

what is the 4th ventricle connected to?

Answer 49

subarachnoid space via lateral (x2) and median (x1) apertures central canal of the spinal cord

Question 50

what is the role of CSF and where does it circulate?

Answer 50

provides mechanical and physical protection to the brain and spinal cord circulates through the ventricles and into the subarachnoid space

Question 51

how is CSF lost from the body?

Answer 51

through arachnoid villi (aka arachnoid granulations) which are protrusions of the arachnoid mater into the dura mater protrude into the DVS allowing CSF to exit from the subarachnoid space into blood

Question 52

where are ependymal cells found and what is their role?

Answer 52

found in choroid plexi present in the lateral, 3rd and 4th ventricles (hang from roof in lateral ventricles!) filter blood plasma to produce CSF