Research methods

Question 1

What is the corchoid plexus

Answer 1

It’s a tissue that’s in each of the brain’s four ventricles - it’s what produces cerebrospinal fluid

Question 2

Where are
1. The cerebral aqueduct
2. The 2 lateral ventricles
3. The third ventricle
4. The fourth ventricle

Answer 2

1. Cerebral aqueduct connects the third & fourth ventricle
2. 2 lateral ventricles are mirrored across the sagittal plane
3. the third ventricle sits between the thalamic nuclei (along the midline)
4. (posterior to other ventricles) - between pons & cerebellum

Question 3

A hollow, enclosed neural tube forms during the first month of human development in the womb. The first cells in this tube are _______ _________ cells. Up until the 8th week of development, these cells only undergo ___________ cell division

Answer 3

A hollow, enclosed neural tube forms during the first month of human development in the womb. The first cells in this tube are [neural progenitor] cells. Up until the 8th week of development, these cells only undergo [symmetrical] cell division: each neural progenitor cell becomes two neural progenitor cells.

Question 4

At which week in embryo development does asymmetrical cell division start

Answer 4

At the 8th week: one of the daughter cell migrates away. The next time that cell divides, it will produce either two neurons or two glia cells

Question 5

When do we have the most neurons in our brain

Answer 5

By the end of the fifth month, we have 85 billion neurons in our brain (many of these neurons die before birth)

Question 6

CT SCANS
1. how do they work
2. pros

Answer 6

1. an x ray beam is delivered through the head to an X-ray detector. The X-ray beam is delivered from all angles.
2. pros - cheap, fast, noninvasive BUT provides blurry image

Question 7

MRIs
1. how do they work
2. pros

Answer 7

1. A magnetic field aligns hydrogen atoms in water molecules in the brain - this causes the atoms to emit their own radio wave to realign with the magnets
2. Provides high spatial resolution, 3-dimensional image of the brain BUT very expensive

Question 8

fMRIs
1. how do they work
2. pros & cons

Answer 8

1. The movement of oxygenated blood distorts magnetic field - shows which areas are using most energy
2. pros: pretty good temporal and spatial resolution and non-invasive BUT expensive

Question 9

DTIs
1. how do they work
2. pros & cons

Answer 9

1. measures the direction and speed of the diffusion of water molecules; used to identify axon tracts
2. pros: high spatial resolution for axon tracts BUT expensive

Question 10

PET scans
1. how do they work
2. pros & cons

Answer 10

1. a radioactive compound (like radioactive sugar molecules) are injected; they detect changes in energy use in the brain
2. pro; can make isotope radiocative & image whatever you want to see cons: expensive & isotopes must be synthesized within hours of imaging

Question 11

macro electrode eeg
1. how does it work
2. pros & cons

Answer 11

1. conductive discs placed on scalp & record electrical changes in the brain
2. pros - cheap, non-invasive & high temporal resolution BUT meaning of waves is hard to interpret & there’S low spatial resolution

Question 12

(animal method) NEURONAL TRACING
1. how does it work
2. pros and cons

Answer 12

1. u inject a molecule to stain a pre or post synaptic connection (afferent or efferent)
2. pros - you can create a brain circuit diagram cons: Molecules don’t fill
   whole neuron

Question 13

Microelectrode EEG (animals): how does it work

Answer 13

Electrode in brain records electrical changes – observe
activity changes with behavio

Question 14

electrical stimulation (animals): how does it work

Answer 14

Electrode in brain delivers electrical current, stimulates
nearby neurons – observe behavioural changes w stim

Question 15

pharmacological manipulation (animals): how does it work

Answer 15

Drug delivered into brain region through guide
cannula – alter cell activity in regio

Question 16

optogenetics (animals): how does it work