Ways Of Studying The Brain Flashcards
fMRI outline:
Measures blood flow in the brain when a person performs a task. When the blood flows there is more oxygen so the doctors can see what part of the brain is being used for the task.
EEG and ERP outline
EEG: measures electrical activity through electrodes attached to the scalp, can detect epilepsy and sleep disorders.
ERP: same as EEG but participant is presented with a stimulus and brain activity is looked at. However have to get multiple readings and an average response is graphed as there may be background data
Post mortem examination outline:
Study the physical brain of a person who displayed a particular behaviour while they were alive that suggests brain damage when they are dead.
fMRI evaluation:
One strength of an fMRI is that the procedure is non invasive, meaning the skin is not broken and tools don’t enter the body. Whereas PET scans are invasive.
One limitation do fMRI is that cause and effect cannot be established as they don’t provide a direct measure of neural activity and only measure changes in blood flow. Whereas
EEG and ERP evaluation
a strength of EEG and ERP is that they are high in temporal resolution, the temporal resolution is every millisecond which means they represent movement to movement brain activity whereas fMRI has low temporal resolution of 1-4 seconds.
a limitation of EEG and ERP is that the spatial resolution is low, this is the smallest feature a scanner can detect. Greater spatial resolution allows psychologists to discriminate between different brain regions with greater accuracy. Whereas fMRI has a high spatial resolution of 1-2mm.
post-mortem examination evaluation
a strength of post-mortem examinations is that they provide detailed examinations of the atomic structure and can access deeper brain regions e.g. hippocampus whereas EEGs can only look at the top part of the brain.
a limitation of post-mortem examinations is that there are many extraneous variables that can effect results/ conclusions. Aswell as any mediacation the patient may have been taking, their age and the length of time between death and examination are all confounding variables that may effect the results
