Paper 2 - Biopsychology - Ways To Investigate The Brain

Question 1

What are the different ways of investigating the brain?

Answer 1

FMRI
Electroencephalogram (EEG)
Event-related potentials (ERP’s)
Post mortem examinations

Question 2

What does a fMRI show?

Answer 2

Brain activity

Question 3

What is a fMRI?

Answer 3

It is a 3D scan providing structural and functional information

Question 4

How does an fMRI work?

Answer 4

It shows changes in brain activity using a string magnetic field and radio waves
1) More oxygenated blood flows to active areas of the brain
2) Molecules in oxygenated blood respond differently to a magnetic field than those in deoxygenated blood
3) therefore more active areas of the brain can be identified 21

Question 5

When are EEGs commonly used?

Answer 5

Sleep studies

Question 6

What can EEG’s also be used to study?

Answer 6

Depression
Schizophrenia
Abnormal EEG’s have also been seen in patients suffering from anorexia nervosa

Question 7

What did Boutos et al (2008) show?

Answer 7

This was a meta analysis which showed that patients suffering from schizophrenia displayed abnormal EEG wave patterns compared to controls

Question 8

What can an EEG potentially be used for?

Answer 8

A diagnostic tool

Question 9

What are the advantages of an EEG?

Answer 9

Invaluable in the diagnosis of conditions such as epilepsy
Contributes to research into ultraradian rhythms of sleep
Extremely high temporal resolution
So it can accurately detect brain activity at a resolution of a single millisecond

Question 10

What are the disadvantages of an EEG?

Answer 10

The results are very generalised (thousands of neurones)
Not useful for pinpointing exact source of neural activity

Question 11

What do ERPs do?
How?

They record activity…

Answer 11

They record activity in response to a stimulus introduced by the researcher

This is because all extraneous brain activity from the original EEG is filtered out leaving only those responses that relate to the specific stimuli

Question 12

What can ERPs be used in?

Answer 12

Memory research
(Location of memory)

Question 13

What did MIltner find?
When?

Answer 13

2000

He found that people with phobais had an ERP of greater amplitude in response to images of the phobic stimulus

Question 14

What are the strengths of a ERP?

Answer 14

It is much more specific to the measurement of neural processes than raw EEG data

Excellent temporal resolution

Question 15

What are the weaknesses of ERPs?

Answer 15

There is a lack of standardisation in ERP methodology between different research studies which makes it difficult to confirm and replicate findings

It is hard to completely eliminate all extraneous data because that includes background noise

Question 16

Describe the 1 study that is involved in post mortem examinations

Answer 16

Brown et al (1986) he discovered that patients who suffered from schizophrenia had enlarged ventricles in their brains

Question 17

What are the strengths of post mortem examinations?

Answer 17

They were really important in providing an early understanding of key processes in the brain
Broca and Wernicke both used post mortem examinations

Improves medical knowledge and it helps generate hypothesis for future studies

Question 18

What are the weaknesses of post mortem examinations?

Answer 18

Determining causation is a problem as you only see the final result

It is difficult to get consent from a dead guy
Eg HM never gave consent but post mortem examinations have been done on his brain

Question 19

Explain the role of MRI scans in investigating the brain?

Answer 19

They create detailed pictures of areas of the brain

Question 20

What are the strengths of fMRIs?

Answer 20

It provides a high resolution picture of brain activity
This means that patterns of activity can be compared rather than just the physiology of the brain
It is non invasive/virtually risk free
Doesn’t rely on radiation

Question 21

What are the weaknesses of fMRI’s?

Answer 21

It has poor temporal resolution (it is 5 seconds behind)
It is expensive
It can only work if the patient stays still
It measures blood flow in the brain. It can’t look at individual neurones

Question 22

What is a haemodynamic response?

Answer 22

A haemodynamic response is where the haem in oxygenated blood is attracted to the magnets on the fMRI. This shows activated ares of the brain, when presented with a stimuli

For example where there is highlighted areas, shows more blood flow, indicated more activity.