Biopsychology: Methods of studying the brain

Question 1

What are the 4 main ways to study the brain?

Answer 1

• Function megnetic resonance imaging (fMRI)
• Electroencephalogram (EEG)
• Event-related potentials (ERP)
• Post-Mortem examination

Question 2

How does an fMRI work?

Answer 2

• Detect changes in blood flow and oxygenation to specific parts of the brain.
• Active parts of the brain require more oxygen, so blood flow is directed to the active areas to meet this demand.

Question 3

How does an EEG work?

Answer 3

• Measures electrical activity within the brain.
• Electrodes are fitted to a person’s head via a skull cap.
• Recording scans show the brainwave patterns generated by action potentials , providing an overall model of brain activity.

Question 4

How does an ERP work?

Answer 4

• Allow for data from EEGs to be further isolated.
• Statistical averaging techniques allow for extraneous brain activity to be filtered out, so only brain activity related to a specific stimulus is left (ERPs).

Question 5

How does a post-mortem examination work?

Answer 5

• A person’s brain is analysed after their death.
• Individuals with abnormal cognitive processes are likely to be subject to this, as a means to establish the likely cause of the abnormality the person experienced.
  -Can involve comparison with a neurotypical brain.

Question 6

2 strengths of fMRI:

Answer 6

• Does not use radiation (unlike other scanning techniques e.g PET) so procedure is virtually risk-free and non-invasive when done correctly.
• Produces images with a high-spatial resolution- providing a clear image of how activity is localised.

Question 7

2 limitations of fMRI:

Answer 7

• Expensive compared to other scanning techniques e.g. PET.
• Has a poor temporal resolution due to 5-second lag time (between firing of activity and image production), so data may not be accurate.

Question 8

2 strengths of EEG:

Answer 8

• Real world application e.g. studying stages of sleep and diagnosis of conditions like epilepsy
• Has an extremely high temporal resolution, so data is very accurate.

Question 9

1 limitation of EEG:

Answer 9

• Not very useful at showing activity localisation, so it is difficult to establish a clear, specific response to stimulus.

Question 10

1 strength of ERP:

Answer 10

• Allow for EEG data to be isolated and produce a more clear model of activity localisation.

Question 11

1 limitation of ERP:

Answer 11

• Lack of standardisation between different research studies, so it is difficult to confirm findings.

Question 12

2 strengths of post-mortem examinations:

Answer 12

• Vital for providing a foundation of early processes e.g. Broca and Wernicke both relied on using post-mortem studies to establish their theories.
• Used to support correlations between abnormal cognitive processes and physical brain abnormalities e.g. HM case study.

Question 13

2 limitations of post-mortem examinations:

Answer 13

• Observed abnormalities to the brain may not be linked to abnormal cognitive processes e.g. may be due to unrelated trauma or decay instead.
  -Ps may not be able to give informed consent.