CNS overview

Question 1

What does the CNS consist of?

Answer 1

Brain and spinal cord

Question 2

CNS of domestic species…..

Answer 2

Is entirely contained within the skull (brain) and vertebral column (spinal cord) and surrounded by 3 protective membranes called Meninges.

Question 3

What is the role of the CNS

Answer 3

1. to receive sensory info from the peripheral nervous system and then send motor info out

Question 4

What are the broad regions of the brain?

Answer 4

1. Cerebrum
2. Diencephalon
3. Brain stem: most cranial nerves arise, includes pons and medulla oblongata
4. Cerebellum: maintaining balance and coordination of movement.

Question 5

Cerebellum

Answer 5

1. Behind the cerebrum
2. “little brain”
3. two lateral cerebellar hemispheres
4. compares what you intended to do with what actually happened: organises and refines motor activity
5. Vital for balance and coordination
6. connected to brain stem by 3 PEDUNCLES of white matter on either side
7. WM branches to look like a tree, grey = highly folded cortex on outside

Question 6

Diencephalon

Answer 6

1. consists of thalamus and hypothalamus

2. Diencephalon and cerebrum = forebrain

Question 7

What is the first part of the brain stem?

Answer 7

Midbrain

Question 8

What makes up grey and white

Answer 8

1. Grey - nerve cell bodies, dendrites and synapses.

2. white matter = axons of CNS nerves

Question 9

What are glial cells, nuclei and tracts

Answer 9

1. GC = supporting cells in the CNS
2. Clusters of cell bodies in the CNS
3. Bundles of axons in the CNS

Question 10

What is decussation?

Answer 10

where info from/ output to the right side of the body is handled by the left side of the brain.
This crossing over is called decussation
“The tracts decussate”

Question 11

Where is white and grey matter arranged in the brain and spinal cord

Answer 11

1. Spinal cord: WM outside, grey in

2. Brain: WM inside, GM outside forming cerebral cortex

Question 12

What is the difference between the cerebrum adn cerebral cortex

Answer 12

1. Cortex = just outside

2. cerebrum = whoel thing

Question 13

What is the basal nuclei

Answer 13

1. grey matter within the white matter of the brain.
2. create stripey appearance called corpus striatum
3. really important for planning and executing movments

Question 14

What is the part of the brain that allows the RHS and LHS to coordinate with one another

Answer 14

1. Corpus Callosum
2. white matter
3. means that if learn something on RHS cna do on LHS

Question 15

Brain surface anatomy of cerebrum and cerebellum

Answer 15

Cerebrum:
1. ridges = GYRI (gyrus)
2. Furrows = SULCI (sulcus)
3. Cerebral hemispheres separated by longitudinal fissure
——————
Cerebrum separated from cerebellum by a transverse fissure
—————————

Cerebellum

1. folds = folia
   - ——————–

Question 16

How can the brain be divided up by

Answer 16

1. anatomically

2. Functionally

Question 17

Where is smell detected? what is the “nose brain”?

Answer 17

1. Rhinencephalon = nose brain
2. Ventral aspect
3. Olfactory bulb = vert rostral aspect
4. Piriform lobe = where most smell is processed
5. Size reflects importance of olfaction to that species
6. It communicates with centres to affect emotion (memory) behaviour and communication

Question 18

What are spaces in the brain called and what for

Answer 18

1. ventricles
2. CNS is bathed in cerebrospinal fluid inside and out
3. V produce and allow CSF to circulate around these interconnected V

Question 19

What are the distinct areas in the brain?

Answer 19

For these functions:

1. front = motor
2. behind motor = somatosensory
3. back = visual
4. bottom = olfactory
5. side = smell

Question 20

What is the associated cortex

Answer 20

1. much of the cortex is termed this

2. it integrates experiences with memories adn emotions

Question 21

What is the limbic system

Answer 21

1. series of tracts and nuclei which are key to emotion learning and memory

Question 22

What is the thalamus

Answer 22

realy point for all sensory info coming into the brain, except olfactory input. Also involved in sleep and wakefulness

Question 23

What is the hypothalamus

Answer 23

Connects the endocrine and nervous systems, and also has important roles in behaviour as it forms part of the limbic syste,

Question 24

What is the brain stem comprised of

Answer 24

1. midbrain, pons, medulla oblongata
2. contains key control centres fr CV, RESP, GI
3. contains the nuclei for most of the cranial nerves
4. midbrain includes the TECTUM which is involved in orientating the head and body in response to sights and sounds (birds)

Question 25

Species difference

Answer 25

1. Degree of folding of cerebral cortex varies depending on their intelligence and how much space available 2. Size and degree of dev of regions varies depending on importance of the functions of a given region

Question 26

What does size of limbic system govern

Answer 26

1. Larger limbic = species driven by instincts, less control over emotions and behaviours

Question 27

What are the anatomical lobes of the cerebrum?

Answer 27

frontal lobe, parietal lobe, occipital lobe, temporal lobe (sides)

Question 28

What are the folds of the cerebellar cortex called?

Answer 28

FOLIA

Question 29

``` Which area is involved in emotion, memory adn learning A cerebellum B Limbic C Pons D Ventricles and say what the others are involved ```

Answer 29

``` ANSWER = B: limbic Cerebellum = coordination Pons = brain stem Ventricles = spaces in brain ```

Question 30

How can we attempt to localise areas of damage?

Answer 30

1. CNS contains groups of neurons in different regions, which are associated with specific functions 2. injury or illness will cause different clinical signs depending on which region is affected, 3. hence we can attempt to localise the area of damage by analysing the clinical signs an animal presents with

Question 31

Cerebrum

Answer 31

1. heavily folded 2. divided into left and right cerebral hemisphere which is separated by a longitudinal fissure 3. arises from the embryonic prosenceph

Question 32

What are clusters of cell bodies within the CNS called and what is the PNS equivalent?

Answer 32

1. Nuclei | 2. CNS equivalent of the ganglia of PNS

Question 33

Why is white matter white?

Answer 33

presence of fat in the myelin around the axons.

Question 34

How is white matter organised? | What is the PNS equivalent?

Answer 34

bunches of axons which are called tracts (the CNS equivalent of anatomical nerves in the PNS), which connect different CNS regions

Question 35

What are 2 main gyrus and sulcus?

Answer 35

1. Cruciate sulcus Forms a cross with the longitudinal fissure 2. Sylvan gyrus on lateral aspect of each hemisphere

Question 36

How can the cerebral hemisphere be broadly divided anatomically?

Answer 36

1. lobes according to which bones of the skull sit outside these areas 2. Frontal, parietal, temporal, occipital