Ways of studying the brain Flashcards
1
Q
How do FMRI scans work?
A
- FMRI scans work by detecting the changes in both blood oxygenation and flow that occur due to neural activities in the brain
- When a brain is more active, it consumes more oxygen and to meet this demand, the blood flow to the specific area increases
2
Q
What do FMRI scans produce?
A
- a 3D image which shows the parts of the brain involved in specific brain processes
- This is important for understanding the localisation of brain functions
3
Q
What is a strength of FMRI scans?
A
- A strength is that FMRI scans unlike PET scans do not rely on radiation.
- FMRI scans are virtually risk free, non - invasive and very straight forward to use
- It also produces images that have a high spatial resolution, that can depict details and provide a clear image of how brain activity is localised
4
Q
What is a weakness of FMRI scans?
A
- FMRI scans are quite expensive compared to other scans
- They have poor resolution as there is a 5 second lag so it is behind on neuronal activity and might not represent memory brain activity
5
Q
How do electroencephalograms work?
A
- An electroencephalogram (EEG) measures electrical activity within the brain via electrodes that are fixed to an individuals scalp using a skull cap
- The cap produces a scan recording that represents the brain wave patterns that are generated from the action of thousands od neurons, providing an account of brain activity
6
Q
What are EEgs meant for?
A
- EEGs are often used by clinicans as a diagnostic tool as unusual arrythmic patterns may indicate epilepsy,tumours or sleep disorder
7
Q
What are the strengths of EEGs?
A
- EEG have been useful in studying the stages of sleep and in the diagnosis of conditions such as epilepsy as sudden bursts can be detected ( real world application)
- EEGs are accurate as they have a high temporal resolution of a single millisecond. This shows its usefulness
8
Q
What is a limitation of EEGs?
A
- the main drawback of EEGs lie in the generalised nature of the information they produce as they do not pinpoint exact neural activity so you can not determine specific locations of neural activity.
9
Q
What are event - related potentials?
A
- ERPs are produced from filtering out all extraneous brain activity and isolating specific stimulus and performance tasks from EEGs.
- This leaves ERPs which are just brain waves triggered by particular events. Researchers have linked ERPs to cognitive processes such as attention and perception
10
Q
What are the strengths of ERPs?
A
- there is much more specifity to the measurement of neural processes than achieved when just using raw EEG data
- they have excellent temporal resolution so they can be used to measure cognitive function deficiets such as the allocation of differential resources
11
Q
What are the limitations of ERPs
A
- the process to create ERPs is not standardised which makes it difficult to confirm findings
- Also it can be difficult to remove extraneous material
12
Q
What are post - mortem examinations?
A
- they are techniques which involve the analysis of a persons brain following their death
- people with PME are likely to have experienced unusual deficiets in cognitive processes or behaviour during their lifetime
- Areas of damage within the brain are examined to determine any cause of afflication a person has experienced
- they also involve the comparison to a neurotypical brain to determine any differences
13
Q
what are strengths of post - mortem examinations?
A
- post - mortem evidence can be vital in understanding key processes in the brain
- Broca and Wernicke relied on post mortem examinations in establishing links between the brain, language and behaviour
- they were also used to study HM’s brain damage
14
Q
What are limitations of PMEs?
A
- damages to the brain may be due to trauma or decay
- post mortem studies also have ethical issues due to lack of informed consent
