Neuroanatomy 2 and 3 - 13.02.23

Question 1

What are the 4 key elements of the blood-brain barrier?

Answer 1

1. Endothelial cell tight junctions (less permeable so chemicals can’t get through)
2. Lack of basement membrane fenestrations (no holes in the basement membrane)
3. Astrocytic end feet (support cells which form an additional layer to stop things getting in)
4. Pericytes (regulate the blood-brain barrier)

Question 2

Why is the Circle of Willis needed in the brain?

Answer 2

So there is always a back up blood supply in case of a blockage

Question 3

Where does venous blood drain?

Answer 3

Into sinuses. Which are channels between 2 layers of dura

Question 4

What is the main artery and vein in the spinal cord?

Answer 4

The anterior spinal vein and the anterior spinal artery

Question 5

How are the lateral ventricles and the third ventricle separated?

Answer 5

By the interventricular foramen

Question 6

What lies in between the third and fourth ventricle?

Answer 6

The cerebral aqueduct

Question 7

What are ependymal cells?

Answer 7

• Line the ventricle
• Small ciliated cells
• They have some epithelial properties
• Glial cells (brain derived)

Question 8

What does the cilia on the ependymal cells do?

Answer 8

Moves the CSF along to the sinuses to be drained so there is no blockage

Question 9

What is made in the Choroid plexus?

Answer 9

CSF is made here and secreted into ventricles
- This plexus also has a large SA due to structure

Question 10

How does CSF drain?

Answer 10

• Via arachnoid granulations (protrusions of the arachnoid mater)
• Peripheral nerves to lymphatics (important nasal mucosa lymphatics)

Question 11

Which cranial nerve does the brainstem not give rise to?

Answer 11

CN I - olfactory nerve

Question 12

What is the limbic system controlling?

Answer 12

• Memory
• Motivation
• Emotion
• Fight or flight

Question 13

What is the Diencehalon?

Answer 13

• The diencephalon is a division of the forebrain. It is situated between the telencephalon and the midbrain
• Containing the thalamus, hypothalamus, and the third ventricle.

Question 14

What are the 3 main groups of nuclei in the thalamus? (functions)

Answer 14

1. Sensory relays
2. Cerebellar and basal ganglia relays to motor frontal lobe
3. Connected to limbic areas of cerebral cortex

Question 15

What does damage to the thalamus cause?

Answer 15

Loss of sensation, pain, movement disorders

Question 16

What are the thalamic connections?

Answer 16

The thalamus projects to various other areas of the forebrain
e.g. To the motor cortex, somatosensory cortex

Question 17

What are the direct and indirect pathways of the basal ganglia?

Answer 17

• They relate to when to do a movement
• The activity of the direct and indirect pathways are modulated by dopamine receptors contained in the substantia nigra

Question 18

What nuclei make up the basal ganglia?

Answer 18

They are called the caudate nucleus, putamen, globus pallidus, subthalamic nucleus, and substantia nigra

Question 19

What is the function of the hypothalamus

Answer 19

Sits on top of pituitary gland and tells it what to do

Question 20

What are the inputs to the hypothalamus?

Answer 20

1. Hippocampus
2. Amygdala
3. Circulating blood

Question 21

What are the outputs to the hypothalamus?

Answer 21

• Pituitary
• Hormones

Question 22

How is the spinal cord covered?

Answer 22

in the 3 layers of mater

Question 23

How does white matter vary in different parts of the spinal cord?

Answer 23

• Least amount on thoracic (not much movement or impulses to control)
• Most in the sacral (a lot of activity)