Neurophysiology 1

Question 1

what is the CNs made up of?

Answer 1

• Brain (protected by the skull, the cranium)

- Spinal Cord (protected by the vertebral column

Question 2

what are the ridges in the brain called?

Answer 2

sulci and gyri

these allow for more of the cerebral cortex to be accomodated in a fixed brain volume

Question 3

what is grey matter?

Answer 3

composed of cell bodies within dendrites that allow neurones to feed into one and other

Question 4

what is white matter?

Answer 4

• composed of axons
• fatty and gelatinous because of the oligodendrocytes that produce myelin
• myelin is wrapped around the neuron for production

Question 5

what are the 3 layers of connective tissue?

Answer 5

1. dura matter
2. arachnoid mater
3. pia mater

Question 6

what is dura matter?

Answer 6

outer layer closest to theskull

tough and durable

Question 7

what is the arachnoid mater.

Answer 7

middle layer - looks like a spiders web

fibrous filaments

Question 8

what is pia mater?

Answer 8

inner layer

tender and soft

Question 9

what is meningitis?

Answer 9

inflammation of the meninges

- different causes but mainly due to bacterial infection

Question 10

what is the treatment for meningitis?

Answer 10

act as fast as possible

- benzylpenicillin or cefotaxime

Question 11

what happens during meningitis?

Answer 11

• there is NO space between the outer & middle layer (the dura & arachnoid)
• there IS a space between the middle & inner layer (the arachnoid & pia)
 this is the subarachnoid space – where the cerebrospinal fluid (CSF) is

Question 12

what may severe head injury cause?

Answer 12

bleed on the brain –> subarachnoid haemorrhage

Question 13

what is epidural pain relief?

Answer 13

• the spinal cord extends 2/3 of the length of the spin, doesn’t extend all the way down
• the lower 1/3 consists of individual nerves/neurons
• epidural pain relief/lumbar punctures are carried out in the lower third region to avoid potential damage to the spinal cord

Question 14

what is the cerebrospinal fluid?

Answer 14

• average adult has around 150mL of CSF that bathes the CNS (around the brain and down the spinal cord)
• CSF has a similar composition to PLASMA
  o similar in terms of the ions that are present
  o there are LESS proteins in the CSF than there are in the plasma
• the CSF fluid is produced by a structure called the Choroid Plexus (a plexus of cells)

Question 15

what is choroid plexus?

Answer 15

plexus of cells that produces the CSF in ventricles of the brain
they are specialised capillary like structures found in the ventricles of the brain

Question 16

what routes can the CSF take?

Answer 16

two major routes

1. central canal - flows through the spinal column
2. through the subarachnoid space via the formaen of magedie - flows around the brain

Question 17

how much CSF is produced. a day?

Answer 17

400-500mL

Question 18

what is hydroephalus?

Answer 18

is a condition where the CSF doesn’t drain properly

• this causes a build-up of CSF fluid
• this increases the pressure on the brain which can lead to brain damage

Question 19

what is the treatment for hydrocephalus?

Answer 19

• surgery, where a shunt is needed to drain the CSF into the rest of the body, so that it can be absorbed and removed naturally

Question 20

what is the blood cerebrospinal fluid barrier?

Answer 20

this is a cellular barrier, that separates the blood from the CSF, barrier consists of:

• Capillary Endothelial Cells – LEAKY
• Ependymal Epithelial Cells – TIGHTLY LOCKED, BARRIE

Question 21

what is the within the choroid plexus?

Answer 21

a series of capillaries which water and ions leak out into the space

Question 22

what is a mutlidrug resistance associated protein?

Answer 22

sits on the side that faces the blood

this protein recognises many drugs, and pumps drugs back into the blood as a protective mechanism = BARRIER

Question 23

what is the P-glycoprotein/

Answer 23

sits on the side that faces the CSF and this protein also recognises many drugs and can pump them into the CSF