3.5. Ways Of Studying The Brain Flashcards
What is a post mortem?
The brain is studied after death to see structural abnormalities
E.g. HM and Tan
Strength of a post mortem
Can clearly see structural damage and differences between “normal” and “abnormal”
Weaknesses of a post mortem
- Unique cases (lack of generalisability)
- Small sample sizes
- Lacks validity due to changes during death
What is an EEG?
Electrodes placed on the scalp to detect neural activity.
Used to look at stages of sleep and disorders, including epilepsy
Strengths of an EEG
+ cheap = lots of research = increased reliability and validity
+ can see more and when a person is thinking
+ safe, painless, and non-invasive (likely to get more ppts)
Weaknesses of an EEG
- poor spatial resolution (hard to read, need lots of research to understand)
- restricted to neo-cortex (outer layer) -> cannot use to study deeper part of the brain safely
What is an fMRI?
Magnetic field and radio waves used to measure blood flow
Measures changes in blood flow when specific tasks are performed to see what area is involved
What are the strengths of an fMRI?
+ Shows tumours and other damage
+ Safe, painless and non-invasive
What are the weaknesses of an fMRI?
- very expensive, decreased research
- cannot use if you have a pacemaker or metallic device = decreased sample
What is an Event Related Potential (ERP)?
Electrodes placed on the scalp to detect neural activity when presented with a stimuli
What are the strengths of an ERP?
+ Ppts can be given different stimuli to see how processing works and which area of the brain is activated in response to the stimuli
+ Shows tumours and other damage
+ Safe, painless and non-invasive
What are the weaknesses of an ERP?
- very expensive, decreased research
- cannot use if you have a pacemaker or metallic device = decreased sample
What is the difference between EEGs and ERPs?
An EEG is a recording of general brain activity, usually linked to states such as sleep and arousal whereas ERPs are elicited by specific stimuli presented to the ppt.
