Week 1 - A - Neuroanatomy 1 - Paul Felts - mainly C.N.S

Question 1

What can the nervous system be divided into?

Answer 1

The central and peripheral nervous system (and the autonomic nervous system)

Question 2

What forms the peripheral nervous system and what forms the central nervous system?

Answer 2

PNS - 12 cranial nerves and the 31 pairs of spinal nerves and their branches CNS - consists of the brain and spinal cord

Question 3

What does the CNS begin as in the early stages of development - approx week 4?

Answer 3

Begins as the neural tube

Question 4

At week 4, there are three primary besicles in the nueral tube, what are these primary vesicles known as? (forebrain, midbrain, hindbrain)

Answer 4

Prosencephalon (forebrain) Mesencephalon (midbrain) Rhombencephalon (hindbrain)

Question 5

The primary vesicles then form secondary vesicles by week 6-8 of development, what are the secondary vesicles known as?

Answer 5

Prosencephalon becomes - telencephalon and the diencephalon The mesenchephalon remains as the mesenchephalon The rhombencephalon becomes the metencephalon and the myelencephalon

Question 6

What do the telencephalon and the diencephalon give rise to?

Answer 6

Telenchephalon - gives rise to the left and right cerebral hemispheres Diencephalon gives rise to thalalmus + hypothalamus

Question 7

What do the mesencehphalon, metencephalon and myelencephalon give rise to?

Answer 7

Mesencephelon - midbrain Metencephalon - pons and cerebellum Myelencephalon - medulla oblonglata

Question 8

Name the three primary vesicles What they divide into to become the secondary vesicles and The major derivatives from the secondary vesicles

Answer 8

Prosencephalon - Telencephalon: left and right cerebral hemispheres Diencephalon: thalamus + hypothalamus Mesenchephalon - Mesencephalon: Midbrain Rhombencephalon - Metencephalon: Pons and cerebellum Myelencephalon: medulla oblongata

Question 9

What forms the brainstem?

Answer 9

The combination of the midbrain pons and medulla

Question 10

Name the secondary vesicles which give rise to the derivatives of the mature brain - start with the outlined brain and work towards the spinal cord

Answer 10

Telencephalon - rise to the cerebral hemispheres Diencephalon - thalamus + hypothalamus Mesencephalon - gives rise to the midbrain Metencephalon - pons and cerebellum Myelencephalon - medulla oblongata

Question 11

Neurones and glial cells are the two principle cells of the central nervous system What are the four parts of a typical neurone?

Answer 11

Have the dendrites, cell body, axon and nerve endings

Question 12

What is the function of the dendrites and axons?

Answer 12

The dendrites are branched propagations from the cell body that recieve information from other neurons and carry it to the cell body Axons carry messages away from the cell body to the other neurons, muscles or glands

Question 13

What are the 4 types of glial cell in the CNS?

Answer 13

Astrocytes Oligodendrocytes Microglia Ependymal cells

Question 14

What are the functions of the 4 types of glial cell?

Answer 14

Astrocytes - role in maintaining the blood brain barrier and environmental homeostasis Oligodendrocytes - produce myelin in the central nervous system Microglia - main immune surveillance cells and antigen presenting cell (APC) Ependymal cells - Ciliated cuboidal/columnar epithelium that line the ventricles

Question 15

Oligodendrocytes produce myelin in the CNS, what produces myelin in the PNS? What is the function of myelin?

Answer 15

Schwann cells produce myelin the PNS The function of myelin is to increase the speed of nerve impulses

Question 16

Throughout the brain, there are ‘bumps and valleys’ (indentations) What are these bumps and valleys properly known as?

Answer 16

Gyrus - bumps and sulcus - valley (indentation) (there are also fissures which are very deep indentations)

Question 17

What is the functions of the gyri and sulci in the brain?

Answer 17

They increase the surface are of the brain increasing the amount of cerebral cortex able to fit in the skull

Question 18

Which slice separates into right and left and which separates into front and back?

Answer 18

Coronal - front and back (anterior and posterior) Sagittal - right and left

Question 19

What is the generalization for the arrangement of grey matter and white matter in the brain?

Answer 19

Generally grey matter on the outside with white matter on the inside - however there is a central cavity of grey matter in the brain

Question 20

What do they grey and white matter in the brain contain?

Answer 20

The white matter contains mainly axons and their support cells The grey matter contains huge numbers of neuron cell bodies

Question 21

What is the difference in arrangement of matter in the spinal cord compared to brain?

Answer 21

Brain White matter inside Grey matter outside with central cavity of grey matter also Spinal cord White matter outside Grey matter inside in a ‘H’ like fashion White matter - aons Grey matter- cell bodies

Question 22

The grey matter in the spinal cord is arranged in horns What is the white matter arranged in?

Answer 22

The white matter is arranged in columns, anterior, posterior and lateral The columns are also known as funiculus - ie dorsal column = dorsal funiculus

Question 23

Why can the white matter columns also be known as fascicles?

Answer 23

This is because the columns are groups of bundled axons which are also known as fascicles

Question 24

What is the main sulcus in the brain that separates the frontal and parietal lobe?

Answer 24

This is the central sulcus

Question 25

Where does the primary motor and primary somatosensory sit in relation to the central sulcus?

Answer 25

The primary motor area sits anterior to the central sulcus in the precentral gyrus The primary somatosensory area sits posterior to the central sulcus in the postcentral gyrus

Question 26

What is the deep groove in the brain that separates the right and left hemispheres? What allows communication between right and left hemispheres?

Answer 26

The deep groove is known as the longitudinal fissure The corpus callasoum allows communication between the right and left hemispheres

Question 27

What is the white matter situated in the inferomedial aspect of both hemispheres of the brain known as?

Answer 27

This would be the internal capsule - nerve signals are transmitted through this space in the axons

Question 28

A small lentil like shaped structure of gray matter is situated in the brain lateral to the internal capsule, what is this known as? It is important in movement control

Answer 28

This is the lentiform nucleus

Question 29

Just superior to the corpus callosum on a saggital slice of the brain is what gyrus?

Answer 29

This would be the cingulate gyris - above this structure is the cingulate sulcus

Question 30

What is the cingulate gyrus involved in?

Answer 30

It is involved in emotion formation and processing/memory

Question 31

What is the sulcus in the occipital lobe where the primary visual cortex is located known as?

Answer 31

This is known as the calcarine sulcus

Question 32

What is the function of the pineal gland? What joins the right and left thalami?

Answer 32

The primary function of the pineal gland is to produce melatonin. This modulates duirnal rhythm The two thalami are joined by the interthalamic adhesion although there is no transmission here

Question 33

What are the borders of the frontal lobe?

Answer 33

The frontal love has the central sulcus as its posterior border with a line drawn to reach the corpus callosum and The lateral sulcus as its lateral border from the temporal lobe

Question 34

What are the borders of the parietal lobe of the brain?

Answer 34

The central sulcus anteriorly The parieto-occipital sulcus posteriorly with a line connecting this to the preoccipital notch (produced by a notch from temporal bone) Bordered laterally by a line from the lateral sulcus

Question 35

What are the borders of the occipital lobe?

Answer 35

It lies posterior to the line made by joining the parieto-occipital sulcus to the preoccipital notch

Question 36

Finally what are the boundaries of the temporal lobe?

Answer 36

The lateral sulcus supreriorly with a line drawn backwards extending from this and a line drawn from the parieto-occipital sulcus to the preoccipital notch posteriorly

Question 37

What are the five lobes of the brain?

Answer 37

Frontal lobe Parietal lobe (x2) Occipital lobe Temporal lobe (x2) and the Insular lobe (x2)

Question 38

Where is the insular lobe normally found and what does it play an important role in?

Answer 38

The insula is hidden from view in the lateral fissure and has an important role to play in the patient's experience of pain and tatse

Question 39

What is another name for the lateral sulcus?

Answer 39

The sylvian fissure

Question 40

What are the three layers of the meninges? they protect the brain and spinal cord

Answer 40

Dura mater Arachnoid mater Pia mater - only a couple of cells thick

Question 41

Where is CSF (cerebrospinal fluid) produced and what is the flow of CSF?

Answer 41

Produced in the choroid plexuses of the ventricles Flow from lateral ventricles down through the interventricular foramen into the 3rd ventricle Then down the cerebral aqueduct (sylvian aqueduct) into the 4th ventricle CSF then exits into the subarachnoid space via lateral apertures and into the central canal of the spinal cord via lateral apertures Once in the subarachnoid space it escapes into the superior saggital sinus via arachnoid granulations

Question 42

Where does the dural venous sinuses drain into?

Answer 42

Drains into the internal jugular vein

Question 43

Which two ventricles are midline structures? What lobes are the four horns of the lateral ventricles situated in?

Answer 43

The third and fourth ventricles Lateral ventricles Anterior horn - frontal lobe Body - parietal love Posterior horn - occipital lobe Inferior horn - temporal lobe

Question 44

What is the nervous system that spans from the oesophagus to the rectum known as?

Answer 44

The enteric nervous system

Question 45

Which arteries supply the different regions of brain?

Answer 45

Blue - anterior cerebral artery - basically most of frontal lobe / parietal lobe Red - middle cerebral artery - temporal lobe / parietal lobe Green - posterior cerebral artery - mainly occipital lobe

Question 46

Which arteries form the circle of willis?

Answer 46

* Anterior cerebral arteries (x2) * Anterior communicating artery * internal carotid arteries (x2) * Posterior communicating artery (x2) * Posterior cerebral artery (x2) * The basilar artery (right + left vertebral arteries) The middle cerebral artery is a branch of the internal carotid artery