Ways of Studying the Brain Flashcards
fMRI
Measures brain activity in specific areas by detecting associated changes in blood flow.
EEG
A record of the brain wave patterns produced by thousands of neurons, providing an overall account of brain activity.
ERPs
Isolating specific responses of neurons to specific stimuli or tasks.
Post-mortem examinations
Correlating behaviours before death with brain structures after death.
POST MORTEMS
This is where a brain is analysed after a person’s death.
In research, individuals whose brains are subject to a post mortem are likely
to have a rare disorder or unusual deficit.
Areas of damage in the brain are examined to establish the likely cause of the application.
This also may involve comparison with a neurotypical brain to assess the extent of the difference.
Shows structure
A03 POST MORTEMS
+ Improve medical knowledge
+ Help generate hypotheses for further study
- Hard to establish causation
- Ethical issues regarding
consent before death
SCANNING
Some scanning techniques can record global neural
activity through the assessment of brainwave patterns.
Others show activity in specific parts of the brain as the brain performs certain tasks and processes.
FMRI
Detects changes in blood oxygenation and flow that occur as a result of neural
activity in specific parts of the brain.
When a brain area is more active it consumes more oxygen, and blood flow is
directed to the active area (haemodynamic response)
fMRI produces 3D images (activation maps) showing which parts of the brain
are involved in particular mental processes.
Helps us to understand localisation of function
Shows structure and function
A03 FMRI
+ Does not rely on use of
radiation
+ Risk free
+ Non-invasive
+ Easy to use
+ Produces a clear picture
- Expensive
- Poor temporal resolution
- Can only measure blood
flow in the brain – cannot
tell the type of brain activity
EEG
Measures electrical activity in the brain via electrodes fixed to a skull cap.
Records the brainwave patterns generated form neurons, giving an overall
account of brain activity
EEG is often used as a diagnostic tool, as unusual patterns of activity may
indicate neurological abnormalities (epilepsy, tumours etc.)
Shows function
A03 EEG
+ Invaluable in the diagnosis
of conditions, e.g. epilepsy
+ Has high temporal resolution
- Information received is
generalised - Cannot pinpoint exact source of neural activity
ERPS
These are types of brainwave that are triggered from particular events.
These can be linked to cognitive processes.
Shows function
A03 ERP
+ More specificity to
measurement
+ Excellent temporal
resolution
+ Many different types of ERP have been identified, and their precise role in cognitive functioning described
- Lack of standardisation in
methodology - Difficult to eliminate
background noise and
extraneous material
