Biopsychology: Ways Of Studying The Brain Flashcards
1
Q
Overview: fMRIs.
A
- Works by detecting changes in blood oxygenation and blood flow that indicate increases neural activity.
- People are asked to do tasks and the brain activity is observed.
- When a brain area is more active, it consumes more oxygen this increases amount of blood flow directed to the active area (haemodynamic response).
- Produces 3-dimentional images showing which particular mental process which is important for establishing localisation of function.
2
Q
Strength: fMRI Is Non-Invasive.
A
- fMRI is non-invasive.
- Unlike other scanning techniques (eg PET) fMRI does not rely on the use of radiation and is safe.
- This makes it an appropriate method to measure brain activity.
3
Q
Strength: fMRI Images With High Spatial Resolution.
A
- fMRI produces images with high spatial resolution.
- It can show detail by the millimetre.
- This means fMRI can provide a clear picture of how brain activity is localised.
4
Q
Limitation: fMRI Expensive.
A
- fMRI is expensive.
- fMRI is expensive compared to other techniques and can only capture an image if the person stays still.
- This limits the appropriateness of fMRI.
5
Q
Limitation: fMRI Has Poor Temporal Resolution.
A
- fMRI has poor temporal resolution.
- This is because there is a 5 second lag between initial neural activity and image.
- This means fMRI may not truly represent moment-to-moment brain activity.
6
Q
Overview: EEGs.
A
- Records changes in electrical activity using electrodes attached to the scalp.
- The scan recording represents the brain wave patterns that are generated from the action of millions of neurons (general), providing an overall account of brain activity.
- Often used as a diagnosis tool as unusual arrhythmic patterns may indicate neurological abnormalities e.g epilepsy.
7
Q
Strength: EEG Invaluable In Diagnosing Conditions.
A
- EEG is invaluable in diagnosing conditions.
- For example it has been used to identify epilepsy and also in understanding the stages of sleep.
- This shows that EEGs are an appropriate way to measure brain activity.
8
Q
Strength: EEG Has Extremely High Temporal Resolution.
A
- EEG has extremely high temporal resolution.
- EEGs can detect brain activity at a resolution of a single millisecond.
- This means that it is more able to represent moment-to-moment brain activity.
9
Q
Limitation: EEG General Information.
A
- EEG information is received from many thousands of neurons.
- The EEG produces a generalised signal from thousands of neurons this means it’s difficult to know the exact source of neural activity.
- Therefore EEG cannot distinguish between the activity of different but adjacent neurons.
10
Q
Limitation: EEGs Does Not Provide A Complete Of Brain Activity.
A
- EEGs do not provide a complete picture of brain activity.
- They only monitor electrical activity in outer layers of the brain.
- Therefore they cannot reveal electrical activity in deeper brain sites.
11
Q
Overviews ERPs.
A
- Records changes in electrical activity using electrodes attached to the scalp but uses a specific stimulus (sensory, cognitive or motor) to see where the activity is.
- Using a statistical averaging technique, all extraneous brain activity from the original EEG recording is filtered out leaving only those response that relate to a specific or task.
- Research has revealed many different forms of ERP and how these are linked to cognitive processes.
12
Q
Strength: ERPs Are Specific.
A
- ERPs are a very specific measurement of neural processes.
- They are more specific than what can be achieved using raw EEG data.
- This means that it is a better method of investigating the brain.
13
Q
Strength: ERPs Excellent Temporal Resolution.
A
- ERPs have excellent temporal resolution.
- ERPs can detect brain activity as resolution of a single millisecond.
- This means that it is more able to represent moment-to-moment brain activity.
14
Q
Limitation: ERPs Lacks Standardisation.
A
- ERPs lack standardisation in methodology between studies.
- This makes it difficult to confirm findings in studies involving ERPs.
- Therefore the reliability of the information regarding the brain’s structure and function is lowered.
15
Q
Limitation: ERPs Extraneous Things Must Be Eliminated.
A
- ERPs must have background noise and extraneous material must be completely eliminated.
- This may not always be easy to achieve.
- This limits the appropriateness of the method for investigating the brain.
16
Q
Overviews: Post-Mortems
A
- Examine abnormalities in the structure of the brain which try to explain psychological abnormalities that people have before death.
- May also compare with neurotypical (normal) brain in order to ascertain the extent of the difference.
17
Q
Strength: Post-Mortems Foundation For Understanding The Brain.
A
- Post-mortems provided the foundation for understanding the brain.
- Broca and Wernicke both relied on post-mortems studies.
- This shows that post-mortem studies have improved medical knowledge and helped to generate hypotheses for further study.
18
Q
Strength: Post-mortems Allow In-Depth Study.
A
- Post-mortems allow for in-depth study of the brain.
- Detailed examinations and measurements of deep brain structures for example hypothalamus that are not measurable by scans can occur.
- This provides us with knowledge of the brain that cannot be gained from less invasive options.
19
Q
Limitations: Post-Mortems Causation Issue.
A
- In post-mortems causation may be an issue.
- Observed damage in the brain may not be linked to the deficits under review but some other related to trauma or decay.
- This limits the appropriateness of the method.
20
Q
Limitations: Post-mortems Ethical Issues.
A
- Post-mortem studies raise ethical issues of consent.
- Before death, patients need to give informed consent , but there is a reason that psychologists want to investigate their brains in the first place.
- This meant that they may not be able to provide informed consent, for example HM.
