Biopsychology: Ways of Studying the Brain NEW Flashcards
Name four ways of studying the brain
Functional Magnetic Resonance Imaging (fMRI)
Electroencephalograph (EEG)
Event Related Potentials (ERP)
Post mortems
What does EEG stand for?
Electroencephalograph
What does fMRI stand for?
Functional Magnetic Resonance Imaging
What does ERP stand for?
Event Related Potentials
What does fMRI identify changes in?
Oxygen levels in the blood due to brain activity
What is the 3D image from an fMRI called?
Activation Map
What has fMRI been used to study?
Which specific parts of the brain are active in particular processes.
In an fMRI, what does increased blood flow show?
When a brain area is active
fMRI is a much safer way of studying the brain than …
PET scans
In terms of resolution, what can we say about fMRI?
High spatial
Low temporal
In EEG, where are the electrodes placed?
On the scalp
What does an EEG detect?
Small electrical changes from brain cell activity.
What have EEGs been used to study?
Sleep Patterns
Arousal
Brain tumors
Epilepsy
How are the electrical signals seen in an EEG?
Graphed over a period of time
In terms of resolution, what can we say about EEG?
High temporal
Low spatial
How is an ERP similar to an EEG?
Electrodes are placed on the scalp
How is an ERP different to an EEG?
EEG shows general activity whereas ERP shows specific brain activity
In an ERP, how is a stimulus presented?
Many times
In an ERP, what is filtered out?
All extraneous brain activity
In terms of resolution, what can we say about ERP?
High temporal
Low spatial
Why is it hard to get meaningful data from a ERP?
It can take many trials as they are affected by external factors e.g. noise
When is a post-mortem conducted?
After death
What do they do in a post-mortem?
Examine and dissect the brain to identify and physical/structural abnormalities.
What do they compare in a post-mortem?
A brain with a disorder/mental process with one that doesn’t show this.
Identify one area of the brain located by post-mortem.
Broca’s area
Why might a post-mortem lack internal validity?
They are affected by extraneous variables such as age, medication or time of death.
When is the use of post-mortem most valuable?
When trying to study the deeper areas of the brain such as the hypothalamus
Why is fMRI a much safer technique to measure brain activity?
It is non-invasive and doesn’t use radiation to identify differences in brain areas
Why are PET scans less safe than fMRIs?
They use small amount of radiation which could lead to potential harm
fMRIs have higher spatial resolution compared to which other brain scanning techniques?
EEG and ERP
Why is high spatial resolution a strength of fMRI?
It can accurately identify specific brain areas involved in behaviour, depicting detail by the millimetre and providing a clear image of how the brain is localised
Name two strengths of fMRI compared to other scanning techniques
Safer technique compared to PET scans
Higher spatial resolution compared to EEG and ERP
Name one weakness of fMRI
Poor temporal resolution
Why do fMRI have poor temporal resolution?
There is around a 5 second time lag behind the image on the screen and the initial firing of neuronal activity
What is a consequence of fMRI having poor temporal resolution?
They may not truly represent moment-to-moment brain activity
EEGs are high in temporal resolution, what does this enable a researcher to do?
Take a real time recording of brain activity rather than a still image of the brain
Why do EEGs provide a greater insight into processes of the brain, such as the activity of the brain during sleep?
Due to being high in temporal resolution and the researcher being able to take real time recordings of brain activity
Why can researchers gain a more accurate measure of general brain activity in a particular task when using an EEG?
Due to being high in temporal resolution and the researcher being able to take real time recordings of brain activity
EEGs enable the researcher to take real time recordings of brain activity. What is a consequence of this?
Researchers can gain a more accurate measure of general brain activity in a particular task /
Researchers can gain a greater insight into the processes of the brain, such as the activity of the brain during sleep
Give one strength of EEGs
High in temporal resolution
Give one weakness of EEGs
Low in spatial resolution
Why is low spatial resolution a weakness when using an EEG?
It can only provide information on general activity in the brain, and cannot pinpoint the exact source of neural activity that is involved in behaviour
What is the difference between an EEG and an ERP in spatial resolution?
EEGs can only provide information on general activity in the brain, whereas ERPs enable a researcher to identify specific brain activity in a particular task
Why might findings from an EEG be less valuable in developing our understanding of the brain?
Due to being low in spatial resolution and researchers not being able to pinpoint the exact source of neural activity that is involved in behaviour
ERPs have high temporal resolution especially when compared to which other brain scan?
fMRI
Why is high temporal resolution a strength when using an ERP?
Brain activity can be identified every millisecond so researchers can see brain activity in real time
In terms of resolution, what is an ERP high and low in?
High temporal resolution, Low spatial resolution
Why do ERPs have poor spatial resolution, compared to fMRI?
They can only detect brain activity in general brain areas rather then identify the specific location of brain activity
Why can it be hard to obtain meaningful data from the use of ERPs?
They can be affected by external factors such as background noise which means that it can take many trials as it is hard to control these other factors
ERPs can be affected by external factors such as background noise. Why is this a weakness?
It can take many trials to obtain meaningful data as it is hard to control these other factors
Post-mortems are the only invasive way to study the brain. Why is this a strength?
It is possible to get a more detailed examination of the brain compared to EEG and ERPs
What deeper area of the brain have researchers been able to study through use of post-mortems?
Hypothalamus
Why is it hard to establish cause and effect with post-mortem studies?
There are many extraneous variables which cannot be easily controlled such as how long a person had a particular disorder/age at time of death/whether they have received drug treatment for their disorder
It is hard to establish cause and effect with post-mortem studies as there are many extraneous variables which cannot be easily controlled.
What is a consequence of this?
It can be more challenging to interpret the role of specific brain areas in behaviour, limiting the internal validity of findings of post-mortem studies
Give an example of an extraneous variable that cannot be easily controlled in post-mortem studies
How long a person had a particular disorder / age at time of death / whether they have received drug treatment for their disorder
Why can it be more challenging to interpret the role of specific brain areas in behaviour when using post-mortems?
It is hard to establish cause and effect with post-mortem studies as there are many extraneous variables which cannot be easily controlled
Which brain scan involves identifying changes in the levels of oxygen in blood?
fMRI
In an fMRI, what happens when a brain area is more active?
More oxygen is used so there is an increase of blood flow to this area
When is an fMRI used?
To identify which specific parts of the brain are active in particular mental processes (showing localisation)
Which brain scan is used to identify which specific parts of the brain are active in particular mental processes (showing localisation)?
fMRI
What do EEGs detect?
Small electrical changes resulting from the activity of brain cells
In which brain scan are electrical signals graphed over a period to see a person’s general brain activity?
EEG
When is an EEG used?
To detect sleep patterns and states such as sleep or arousal / To diagnose conditions such as brain tumours and epilepsy
Which brain scan is used to detect sleep patterns and states such as sleep or arousal / To diagnose conditions such as brain tumours and epilepsy?
EEG
How is an ERP different to an EEG?
ERPs show the brain’s response to a specific stimulus, EEGs show general brain activity
How do ERPs show the brain’s response to a specific stimulus?
1) A stimulus is presented to an individual many times and brain activity is measured
2) All extraneous brain activity from the original EEG recording is filtered out
3) Only those responses that link to the presentation of the stimulus is left
What do ERPs look like?
Graphed, and a base line measure line is shown with a test line to the difference in brain activity to specific stimuli
When is an ERP used?
To study a range of cognitive processes such as attention, memory or perception in response to a specific stimuli
Which brain scan is used to study a range of cognitive processes such as attention, memory or perception in response to a specific stimuli?
ERP
What two types of brain are compared in a post-mortem?
Healthy brains, Those with a disorder
Who are post-mortems mainly used on?
People who have a rare disorder or defects
In a post-mortem, the brain of a dead patient is examined and dissected to see if there are any physical/structural abnormalities.
What is this brain then compared to?
A brain that does not show this behaviour or mental process
Give an example of how post-mortems have been used to identify localised areas of the brain
Identification of Broca’s area as an important brain area for speech production
