ways of studying the brain

Question 1

when are brain scanning techniques used?

Answer 1

for medical purposes and in the diagnosis of illnesses, or to investigate localisation

Question 2

how do fMRIs work?

Answer 2

they detect changes in both blood oxygenation and flow that occur as a result of brain activity in specific areas of the brain. When an area is more active, it consumes more oxygen so blood flow is directed to that area.

Question 3

what images do fMRIs produce?

Answer 3

3D images showing which parts of the brain are involved in particular mental processes

Question 4

why are fMRIs important?
(What to they support)

Answer 4

it has important implications for our understanding of localisation of function

Question 5

what do EEGs measure?

Answer 5

electrical activity within the brain

Question 6

how do EEGs work?

Answer 6

electrodes are fixed to the patients scalp using a skull cap. The scan recording represents the brainwave patterns that are generated from the action of thousands of neurones and this provides an overall account of brain activity

Question 7

when are EEGs used?

Answer 7

used by clinicians as a diagnostic tools unusual arrhythmic patterns of activity may indicate neurological abnormalities such as epilepsy or brain tumours

Question 8

How do ERPs work?

Answer 8

using a statistical averaging technique, all extraneous brain activity from an original EEG recording is filtered out, leaving only responses that relate to the events being studied. What’s left are ERPs, types of brainwaves that are triggered by particular events.

Question 9

what does a post mortem involve?

Answer 9

the analysis of a persons brain following their death. it may involve a comparison with a neurotypical brain in order to find the extent of the difference

Question 10

when would a person be more subject to a post mortem examination?

Answer 10

those who have a rare disorder and have experienced unusual deficits in cognitive processes or behaviour during their lifetime.

Question 11

why do post mortems occur?

Answer 11

to try and establish the likely cause of affliction the person experienced.

Question 12

what is a strength of fMRIs? (radiation)

Answer 12

unlike other scanning techniques, it doesn’t rely on the use of radiation. If administered correctly, it is virtually risk free, non invasive and straight forward to use. It produces images that have a very high spatial resolution, depicting detail by the millimetre and provides a clear pic of how brain activity is localised. This means fMRI can safely provide a clear pic of brain activity

Question 13

what is a limitation of fMRIs? (£)

Answer 13

it is expensive compared to other neuroimaging techniques. It has poor temporal resolution as there’s a 5 second time lag between the image on screen and the initial firing of neuronal activity. This means fMRI may not truly represent moment-to-moment brain activity

Question 14

what is a strength of electroencephalograms? (EEGs, diagnosis)

Answer 14

useful in studying the stages of sleep and in the diagnosis of conditions such as epilepsy, a condition characterised by random bursts of activity in the brain that can easily be detected on screen. Unlike fMRI, EEG has extremely high temporal and can accurately detect brain activity at a resolution of a single millisecond. This shows the real world usefulness of the technique

Question 15

what is a limitation of EEGs? (pinpointing)

Answer 15

the EEG signal is not useful for pinpointing the exact source of neural activity. This is because of its generalised nature. Therefore it doesn’t allow researchers to distinguish between activities originating in different but adjacent locations

Question 16

what is a strength of event related potentials (ERPs)? (specific)

Answer 16

They bring much more specificity to the measurement of neural processes than could ever be achieved using raw EEG data. They have excellent temporal resolution when compared to neuroimaging techniques such as fMRI. This means they are used to measure cognitive functions and deficits such as the allocation of attentional resources

Question 17

What is a limitation of ERPs? (pure data)

Answer 17

critics have pointed to a lack of standardisation in ERP methodology between different research studies which makes it difficult to confirm findings. A further issue is that in order to establish pure data, background ‘noise’ and extraneous material must be completely eliminated. This is a problem as this may be difficult to achieve

Question 18

What is a strength of post mortems?

Answer 18

The evidence from pm was vital in providing a foundation for early understanding of key processes in the brain. Broca and Wernicke both relied on post mortems when establishing links between language and the brain. This is a strength because it shows that they are extremely useful and provided psychologists with extremely useful information