Schizophrenia- Biological Flashcards
What did Claridge and Davis (2003) argue?
The contribution of genetic influence is one of the few factual certainties of schizophrenia
What did Rosenthal (1963) conduct a study on and what did he find?
Identical quadruplet girls.
All developed schizophrenia at different ages and severities.
Probability of this was 0.000001%.
Grandmother was a paranoid schizophrenic.
Father may have had undiagnosed schizophrenia.
The girls had a terrible upbringing.
What were the ethical and methodological issues with Rosenthal (1963) study? (5)
Privacy
Right to withdraw
Subjective
Low ecological validity
Time consuming
What is a twin study in terms of researching schizophrenia?
A study aiming to reveal the influence of genetics on schizophrenia through monozygotic and dizygotic twins by looking at concordance rate.
What are monozygotic twins?
Twins from one egg (identical)
What are dizygotic twins?
Twins from two seperate eggs (fraternal)
What is concordance rate?
A measure of genetic similarity. (to what extent twins share the same characteristics)
What did Gottesman (1991) find out about concordance rate?
That MZ twins have about 48% concordance rate, while DZ twins have a rate of about 17%
Why are twins studies limited in generalisability? (2)
Twins are used so findings may not apply to other children.
Twins may act more similar than they actually are.
Why is reliability an issue in twin studies?
Identification of MZ and DZ is not perfect, especially before the 1980’s so may be wrongly assigned.
Why is validity an issue in twin studies?
Confounding variables present: even though twins have the same home does not mean they had the same upbringing.
-favouritism, different relationships & interests
Name the ethical issues involved twin studies.
Consent
Risk of children feeling weird/different
Damage to self confidence
What is a family study?
Studying the concordance rate of family members to determine genetic basis
What is an adoption study?
Studying concordance rate between adopted children and their birth families.
If concordance rate is higher with the birth family, it suggests genetic basis.
If concordance is higher with adoptive family, it suggests environmental basis.
What does research in adoption studies suggest?
That environmental influence is needed to trigger the gene.
