biological explanations of schizophrenia

Question 1

family studies

Answer 1

genetic basis

Question 2

irving gottesman (1991) - findings

Answer 2

-chance of developing SZ increases in line with genetic similarity to a relative with SZ
(e.g. MZ - 48%, DZ - 17%, children - 13%, siblings- 9%)

Question 3

gottesman - conclusions

Answer 3

-SZ is partly genetic in origin
-concordance aren’t 100% so therefore partly environmental

Question 4

candidate genes - polygenic

Answer 4

-lots of genes involved in development of SZ
- most likely ones involved in coding for neurotransmitters (dopamine)

Question 5

candidate genes - aetiologically heterogeneous

Answer 5

-not one set cause of SZ
-combinations of genes and other factors can lead to SZ

Question 6

the role of mutation

Answer 6

-caused by radiation, poisoning or viral infection

Question 7

strength

Answer 7

point - research support
evidence- Tienari et al (2004) found that adopted children of biological mothers with SZ were more likely to develop the disorder than adopted children with mothers without SZ
explain- suggests that SZ is genetic

Question 8

weakness

Answer 8

point - twin studies
evidence - MZ twins are allocated as Mz through sight also MZ are treated the same, same room, same clothes etc
explain - concordance rates also say that SZ isn’t purely biological due to the influence of environmental factors/influence

Question 9

environmental factors

Answer 9

-smoking THC-rich cannabis (only if there is a genetic predisposition - family member who had SZ)
-childhood trauma (67% of SZ patients reported childhood trauma compared to matched control (no disorder) with 38% reporting childhood trauma
explain - doesn’t cause SZ but childhood trauma is associated