Ways of studying the brain Flashcards
How does fMRI work?
o Detects changes in blood oxygenation and flow that occurs as a result of neural activity in specific parts of the brain
o When a brain area is more active in consumes more oxygen so there is an increased demand for blood
What are the strengths of fMRI?
o It doesn’t rely on the use of radiation
o Virtually risk-free, non-invasive and straight forward to use
o Produces images that have a high spatial resolution
What are the weaknesses of fMRI?
o It’s expensive compared to other techniques
o Can only capture a good image if a person stays perfectly still
o Poor temporal resolution
o Can only measure blood flow, doesn’t hone in on activity of individual neurones
How does EEGs work?
o Measures electrical activity within a brain via electrons that are fixed onto an individual scalp
o Scan recording represents the brain wave patterns that are generated from action of neurones
Strengths of EEGs?
o Proved invaluable in diagnosis of condtions such as epilepsy
o Contributed to understanding of the stages involved in sleep
o High temporal resolution
Weaknesses of EEGs?
o Generalised nature of information received
o Can’t pinpoint the exact source of neural activity
How do ERPs work?
o Brains electro physical response to a specific sensory, cognitive or motor event can be isolated throughout statistical analysis of EEG data
Strengths of ERPs?
o Limitations of EEGs are addressed
o Bring much more specificity to the measurement of neural processes
o Good temporal resolution
Weaknesses of ERPs?
o Critics have pointed to a lack of standardisation in ERP methodology between different research studies which makes it difficult to confirm findings
How do post-mortems work?
o Brain is analysed after death to determine whether certain observed behaviours during the patient’s lifetime can be linked to abnormalities in the brain
Strengths of post-mortems?
o Vital in providing a foundation for early understanding key processes in the brain
o Broca and Wernicke both relied on post-mortem studies
Weaknesses of post-mortems?
o Causation is an issue
o Observed damage to the brain may not be linked to the deficits under review but some other trauma or decay
o Issue of ethical issues, HM lost ability to form memories and couldn’t provide fully informed consent but post-mortem research was still done on his brain
