Ways of Studying the Brain Flashcards
What are neuropsychological tests?
Tests designed to measure the verbal and non-verbal behaviours of those suffering brain damage
What are neuropsychological tests used for?
The results are compared with those of individuals not suffering brain damage
They can be used to indicate the type and severity of brain damage someone has suffered, as well as assessing people with learning disabilities and developmental disorders
What are lesion studies?
Experimental studies, usually done on animals, where small lesions are made, or small parts of the brain are removed, in order to test their effects on behaviour
The aim is to link the behaviour to the affected areas of the brain
What is the problem with lesion studies done on humans?
They are done only on those who already have lesions, and therefore there is no control
What is TMS and how is it used?
Transcranial magnetic stimulation
It is used to create a temporary lesion in the brain, which gives more control to the human lesion studies while still being ethical
What is EEG?
Electroencephalography
Electrodes are attached to the scalp which record the activity of groups of neurons
How is EEG used?
Specific patterns that can be seen on a trace appear to correspond to different psychological states or states of consciousness
We can see brain death
We can distinguish between different sleep states as well as between sleeping and wakefulness
We can use it to detect epilepsy
What is MRI and how is it used?
Magnetic resonance imaging
It is a measure of structure and creates images based on how atoms in living tissue respond to a magnetic pulse
What is DTI and how is it used?
Diffusion tensor imaging
It is a measure of structure and measures how water molecules diffuse in tissue to provide information about how structures and pathways in the brain are aligned
What is PET and how is it used?
Positive emission topography
It is a measure of activity, including that of metabolism, blood flow and neurotransmitters
It requires that the participant is injected with a radioactive substance, which travels to the active parts of the brain - the scanner then detects energy emissions while the person is performing a task, showing which areas of the brain are most active at the time
What is the problem with PET?
Due to the levels of radiation than must be injected, it cannot be used with certain groups (children, pregnant people) and it cannot be conducted more than once in a year on the same subject, making follow up studies difficult
What is fMRI and how is it used?
Functional magnetic resonance imaging
It is a measure of activity, and produces pictures of blood flow in the brain, each taken less than a second apart, so it is possible to see changes in activity as they happen
What is fNIRS and how is it used?
Functional near-infrared spectroscopy
It is a measure of activity, and involves shining light into the brain and measuring how it is reflected back
What is one benefit and one drawback of fNIRS?
Benefit: it can be used on moving participants unlike fMRI
Drawback: it has a limited use compared to fMRI as it creates less of a precise map and can’t go as deep into the brain
What is the problem with the fact that scans focus on localised brain areas?
Interconnectivity is important, as lots of different areas in the brain often work simultaneously to achieve a particular function, and this can be lost when only one area is focused on at a time
