Ways of studying the brain Flashcards
(18 cards)
What are 3 types of scanning technique?
Functional magnetic resonance imaging (FMRI)
Electroencephalogram (EEG)
Event-related potentials (ERPs)
What does FMRI stand for?
Functional magnetic resonance imaging
How do FMRIs work?
When a part of the brain is active, it uses more oxygen
fMRI detects changes in blood oxygen levels and flow
It creates a 3D image showing which areas of the brain are more active during certain tasks (like thinking, speaking, or looking at pictures
Why are FMRIs useful in psychology?
Helps researchers see which parts of the brain are involved in different mental processes.
Non-invasive (no surgery or radiation)
Provides high spatial resolution (detailed images of where activity is happening)
What are some strengths of FMRIs?
- Produces detailed and accurate images of brain activity
- Not invasive
- Can study live brain activity during real tasks
What are some limitations of FMRIs?
- Not a direct measure of neural activity in particular brain areas as it only measures changes in blood flow
- Poor temporal resolution, the fMRI doesn’t show exactly when brain activity happens, only roughly (delay between brain activity and FMRI detecting it)
- Overlooks the networked nature of brain activities it focuses only on localised activity (communication is critical to mental function)
What does EEG stand for?
Electroencephalogram
How do EEGs work?
Measure electrical activity in brain
- Electrodes placed on the scalp detect small electrical charges resulting from the activity of brain cells
EEG picks up signals and records patterns of brain activity over time.
It’s often used to study things like sleep, epilepsy, or general brain function.
What are some strengths of EEGs?
- Records brain activity in real time rather than a still image of a passive brain
- Useful in clinical diagnosis e.g. epilepsy
What are the limitations of EEGs?
- Can only detect activity in superficial regions of the brain
- Not useful in pinpointing the exact source of the activity - not allowing researchers to distinguish between activities orientating in different but closely adjacent locations
What does ERPs stand for?
Event-related potentials
How do ERPs work?
Type of brain scan technique that measure small electrical changes in the brain in response to specific stimuli or events
- They are a form of EEG but focus on specific responses rather than general brain activity
Researchers present a stimulus (like a picture, sound, or word) repeatedly and average the brain’s electrical response to isolate relevant signals
EPRs allow psychologists to study cognitive processes such as attention, perception, and decision-making with very high temporal resolution (milliseconds)
What are some strengths of EPRs?
- Excellent temporal resolution, making them ideal for studying the timing of brain activity.
- Useful for investigating covert cognitive processes that don’t require physical movement
What are some weaknesses of EPRs?
- Poor spatial resolution (they don’t show where in the brain the activity is coming from very precisely)
- Require many trials to get reliable data due to the tiny signals involved
What are post-mortem examinations?
Researchers examine people and once they die examine their brains to look for abnormalities that may explain certain behaviours
What is an example of a case where post-mortems were used?
Broca’s work with a patient, Tan - found a lesion now known as Brocas area
What are some strength of post-mortems?
- Allow for a more detailed examination of anatomical and neurochemical aspects of the brain than would be possible with the sole use of scanning techniques
- Useful in understanding the origins of mental disorders such as schizophrenia (Harrison)
What are some weaknesses of post-mortems?
- Since it’s performed after death, it can’t measure function or activity, only structure - this also ,makes it retrospective because the researcher is not able to follow up on anything that arises during examination
- Brain may have changed after death (e.g. decay) or due to age, medication, or illness, making results less reliable
