Ways of Studying the Brain Flashcards
Name the 4 ways of studying the brain.
fMRI, EEG, ERP, Post Mortem
What do fMRI scans detect?
Changes in the flow of oxygenated blood in the brain.
How are fMRIs interpreted?
Where there is more activity in the brain, there is more oxygenated blood in that area
What is the name of the response where more oxygenated blood is sent to a more active area?
Haemodynamic response.
Describe what an image produced by an fMRI scan would look like.
The image is a 3D photo of the brain. The lighter the area, the more neural activity.
How are fMRI scans able to detect blood flow in the brain?
The magnetic field emitted by oxygenated blood is different to deoxygenated blood.
What do EEGs measure?
Electrical activity in the brain.
How do EEGs measure brainwaves?
Electrodes are fixed to the scalp.
What are EEGs usually used for?
How are they used for this purpose?
They are used as a diagnostic tool for neurological issues such as epilepsy.
Any unusual arrhythmic patterns of brain activity can be detected.
What are ERPs used to measure?
The response to a specific stimulus or task.
Describe what an ERP is.
A statistical averaging technique that filters extraneous activity from the original EEG recording to leave only those responses that relate to the presentation of a specific stimulus/task.
What is a brain post mortem?
The brain is cut open after death to see if there is any anatomical cause for any rare disorder or unusual deficits in cognitive/behaviour.
How might the extent of neurodiversity be understood?
The brain may be compared to a neurotypical brain.
Explain the strength of fMRI, EEGs and ERPs being non invasive. Compare this to post mortems.
Why are brain scans better overall in terms of the volume of people being studied?
All 3 of these scanning techniques take place outside of the brain, meaning that the person being studied is likely to feel more comfortable. Additionally, they do not release any radiation, meaning that no one will be harmed as a result of the scan. On the other hand, post mortem studies are invasive as they require the brain to be cut up and examined. This means that brain scans are a better technique for studying the brain as they allow a higher volume of people to take part in them, meaning more research can be done to increase our understanding of brain function.
Explain the limitation of fMRI scans having poor temporal resolution.
Compare this to EEG/ERPs temporal resolution.
Temporal resolution refers to the accuracy of the scanner in relation to time. The temporal resolution of fMRI scans is around 5s. This means that what we view on the scan is slightly different to what is happening in real time, in the brain. This is worse than other scanning techniques (EEG/ERP) which have a high temporal resolution of 1 millisecond. This means that making conclusions about neural activity with a high degree of accuracy is difficult.
