Brain Structure as an Explanation for SZ

Question 1

Outline 6 points about brain structure

Answer 1

• Death/decay of tissue in brain areas, enlarged ventricles
• Frontal/temporal lobe smaller
• Reduction of grey matter
• Prefrontal cortex smaller, which is involved in speech, decision making and willed actions
• Factors before birth. Causes enlarged ventricles, e.g. mom contracts influenza during pregnancy
• During conception of foetus during famine causes nutritional deficiency

Question 2

Supporting research?

Answer 2

P- Suddath et al (1990)
E- Used MRI to obtain pictures of the brain structure of MZ twins in which 1 twin had SZ. The SZ twin generally had more enlarged ventricles. The differences were so large that the twins could be easily identified from the brain images in 12/15 pairs
E- Shows that brain structure, in particular enlarge ventricles, could be a cause of SZ

Question 3

Strength?

Answer 3

P- Reliable
E- Use of brain scans
E- Gathers scientific, objective data

Question 4

Weakness?

Answer 4

P- Reductionist
E- Alternative explanation of SZ is the dopamine hypothesis. Sufferers have increased D2 receptors in brain and increased dopamine levels
E- Must consider more than one level of explanation. As an explanation this is better than brain structure as has more application - drug treatment

Question 5

Weakness?

Answer 5

P- Data is correlational
E- Associations only identified because its correlational , brain scans are not used as diagnostic tools
E- Causation cannot be inferred, lowers validity