RM 1: brain scans (BP)

Question 1

Computed tomography scan

CT scan: strengths and weakness

Answer 1

Strength:
+ Very quick to conduct and give accurate details of brain structure (quality of images can show tumours, lead to our better understanding of how they develop).

Weakness:
- However, the image produced is only structural it does not provide any detail about how the brain functions.
- Potential risks due to x-ray radiation.

Question 2

Positron Emission tomography

PET scan: strengths and weaknesses

Answer 2

Strength:
+ A strength of this scan is that it indicates the specific areas of the brain that are involved in the experience. It can provide evidence for localisation of function, e.g. participants and researchers can see which areas of the brain are linked to that activity.

Weakness
- A radioactive injection is used which is invasive and with the potential to damage cells and tissues in the body and some individuals can also have allergic reactions to FDG. This limits the usage of these scans for research.
- Also, they only show how the brain functions and do not allow actual damage to be seen.

Question 3

Functional Magnetic Resonance Imaging

FMRI scan: strengths and weaknesses

Answer 3

Strength
+ A strength of an fMRI is that is that the images shown in an fMRI are extremely clear and inform us of what areas are most active during a given task.

Weakness
- In order for an fMRI to be effective, the patient must remain perfectly still. This is a weakness because keeping still may be difficult for certain people, such as children or people with severe anxiety, which limits the use of this method for some types of research.
- Moreover, anyone with a cardiac pacemaker or who has had any recent metal surgical implants would not be able to have those scans due to the high-magnetic fields in fMRI scans.

Question 4

OVERALL

Strengh of brain scans

Answer 4

I - Brain scans are reliable and objective ways to measure brain activity.
J - By comparing these measurements against observed behaviours, we can establish connections between brain areas and behaviours. An example of this is Raine et al (1997) study where it was shown that murder showed significantly less activity in the prefrontal cortex left amygdala left hippocampus and cerebral cortex the murderers however had high levels of activity in the right amygdala and right hippocampus

Question 5

OVERALL

Weakness of brain scans

Answer 5

• As many of these scans rely on radiation, magnets or their participants to lay still. These brain scans might not be viable for groups such as children or people with metal implants. As such may not be a suitable way to investigate the brain in all cases.
• Moreover, brain scans do NOT tell the whole story of aggression. It just lets us know that certain areas are more active in more aggressive individuals. But we aren’t sure if these brain areas activation CAUSES the aggression. Some research argues aggressive behaviours cause the brain’s structures to change. (correlation not causation)