Introduction to Clinical Neuroscience

Question 1

What lobe is the most developed in humans?

Answer 1

→ The frontal lobe

Question 2

What is the dura and what does it contain?

Answer 2

→ the ‘bag’ that surrounds the brain

→ contains CSF that surrounds the brain

Question 3

What is the function of the dura?

Answer 3

→ Cushions the brain from impact

Question 4

How much energy does the brain use?

Answer 4

→ 20-30% of the energy

Question 5

What makes up grey matter?

Answer 5

→ astrocytes
→ Neurons
→ glia

Question 6

What are the connections between grey matter?

Answer 6

→ white matter

Question 7

What do dendrites do?

Answer 7

→ They receive signals from other neurons and get processed by the cell body and the signal is transmitted to other cells

Question 8

What happens when the frontal lobe is damaged and give an example?

Answer 8

→ Phineas Gage
→ Personality changes
→ irreverent, impatient

Question 9

What is Alzheimers?

Answer 9

→ Deposition of proteins that damage the brain

Question 10

What do products of blood breakdown show up as on an X-Ray?

Answer 10

→ Bright marks

Question 11

What creates MRI images?

Answer 11

→ magnets within us

Question 12

How does NMR work?

Answer 12

→ Hydrogen atoms have protons
→ Nucleus spins and acts like a small magnet
→ A radiofrequency pulse is given out which interacts with all the protons
→ Protons spin and generate a signal

Question 13

What is isotropic diffusion?

Answer 13

→ the same diffusion in all directions

Question 14

What is anisotropic diffusion?

Answer 14

→ Strong lateral diffusion but perpendicularly weak

Question 15

How can water move in white matter tracts?

Answer 15

→ it can diffuse easily

→ restricted from moving side to side

Question 16

What is anisotropy a marker of?

Answer 16

→ How much damage is done

Question 17

Describe the principle that is used when measuring brain activity?

Answer 17

→ Deoxy Hb is paramagnetic
→ it causes a reduction in the MRI signal intensity
→ when doing something (talking) more O2 and glucose are needed
→ Deoxy Hb is washed out
→ The signal should increase

Question 18

How do PET scans work?

Answer 18

→ Injected radionuclides
→ they decay by emitting a positron
→ It doesn’t travel very far before bumping into an electron
→ the two join together and annihilate and emit a gamma ray
→ The gamma rays are emitted in equal and opposite directions to conserve momentum

Question 19

Give an example of how Parkinsons is detected using a PET scan?

Answer 19

→F18 nucleus is attached to dopamine
→ this is picked up by dopamine receptors
→ in normal controls there is a lot of dopamine receptors in the caudate and putamen
→ in patients with parkinsons they are reduced so the signal is less bright