Neuroscience techniques

Question 1

What is resolution

Answer 1

the extent to which a method can sample the brain’s function

Question 2

What is spatial resolution

Answer 2

Precision in the localization of brain activity/function

Question 3

What is temporal resolution

Answer 3

Precision in the timing of brain activity/function

Question 4

What do structural MRIs do

Answer 4

Produces detailed images of the brain to investigate the structure

Question 5

What do sMRIs rely on?

Answer 5

The magnetic properties of hydrogen nuclei

Question 6

What do structural MRIs measure

Answer 6

Size of cortical matter, size of specific parts of the brain, differences in brain structure between people

Question 7

What are advantages of structural MRIs

Answer 7

Non invasive, little health risk, high spatial resolution

Question 8

What are disadvantages of structural MRIs

Answer 8

cramped area, expensive, only information on the structure alone

Question 9

What does a functional MRI measure

Answer 9

Changes in the concentration of oxygen in the blood relating to neural activity

Question 10

What is the BOLD signal

Answer 10

Blood oxygen level dependent

Question 11

What is the haemodynamic response

Answer 11

When the BOLD signal evolves over time as a response to increase in neural activity

Question 12

What are the 3 phases in the haemodynamic response

Answer 12

Initial dip, overcompensation, undershoot

Question 13

What happens in the initial dip of the haemodynamic response

Answer 13

neuronal consuming of oxygen, small rise of deoxyhaemoglobin so a reduction of the BOLD signal

Question 14

What happens in the overcompensation phase of the haemodynamic response

Answer 14

increased consuming of oxygen, more blood flow, BOLD signal increases due to increase of blood flow

Question 15

What happens in the undershoot of the haemodynamic response

Answer 15

blood flow + oxygen consumption dip and return to original levels, relaxation of venous system, temp increase of deoxyhaemo

Question 16

When are functional MRIs used?

Answer 16

Investigating which brain areas are active under certain conditions, the differences of brain activity between people, changes in brain activity pre and post interventions

Question 17

What did Milne et al find?

Answer 17

Memory issues are reported in patients with MDD and reflects the hippocampal changes. Increased activity in the right hippocampal area when comparing the control and people with MDD

Question 18

What are the advantages of functional MRIs

Answer 18

non invastive, good spatial resolution, low health risk

Question 19

What are disadvantages of functional MRIs

Answer 19

noisy, cramped space,
very expensive machine,
poor temporal resolution,
indirect measure of brain activity

Question 20

What do EEGs do

Answer 20

Investigate the electrical activity of the brain

Question 21

How do EEGs work

Answer 21

Neurons produce electrical charges that form patterns called brain waves. The electrodes detect brain wave. The EEG machine amplifies the signals and records them in a wave pattern

Question 22

When are EEGs used

Answer 22

Investigate brain activation with milliseconds resolution, investigate changes in brain activity between groups, biomarkers of disorders. Patterns of brain waves (alpha, beta, gamma, theta) each associated with specific cognitive functions/behaviours. For ERPS

Question 23

Where do EEGs signals originate

Answer 23

In the post synaptic dendritic

Question 24

What are the currents for EEGs signals

Answer 24

Passive and active currents

Question 25

What are advantages of EEGs

Answer 25

Non-invasive
Inexpensive and flexible
Good temporal resolution (ms range)
Direct measure of brain activity

Question 26

What are disadvantages of EEGS

Answer 26

Poor spatial resolution
Mostly restricted to activity from cortical areas

Question 27

What do ERPs measure

Answer 27

The amount of electrical activity due to a stimulus

Question 28

What gives the peaks in an ERP wave

Answer 28

Dipoles which summate to the skull

Question 29

What are dipoles

Answer 29

Separation of electrical charges that create an EM field from different neurones and regions

Question 30

What do TMS do

Answer 30

Activate or modulate neuronal activity in the brain
which allows infering of brain behaviour relations

Question 31

What happens when there is a change in the electric current in TMS

Answer 31

A magnetic field is created which will incrase the rate of change in the electric current which induces a secondary electric current into the nearby wire

Question 32

Where is the secondary current induced

Answer 32

In neurons below the stimulation site

Question 33

When are TMS used

Answer 33

To investigate the relationship between brain areas and behaviour. Stimulating the areas of the brain with decreased activity

Question 34

What are advantages of TMS

Answer 34

Non-invasive
Quick
Relatively cheap

Question 35

What are disadvantages of TMS

Answer 35

Some side effects (e.g. headaches, scalp pain, dizziness)
Still not sure how long the effects last
Poor spatial and temporal resolution

Question 36

What do animal models do

Answer 36

They target lesion of defined brain areas with targeted training and analysing the brain structures

Question 37

How is animal models invasive

Answer 37

There is invasive recording of neural activity and brain stimulation

Question 38

What does animal models allow

Answer 38

Causal conclusions