biological explanations- schizophrenia Flashcards
genetic factors
predetermine whether individual develops disorder
what type of studies are used
family, twin and adoption studies offer a way of validation the role of genetic factors as causal
family studies- closeness
the closer the degree of genetic relatedness the greater the risk
what did Gottesman 1991 find
children with 2 schizophrenic parents have a concordance rate of 46%
children with one parent 13%
issue with family studies
raised in same environment not heredity
twin studies concordance rates of genes
MZ twins who share 100% of their genes should be more concordant for heredity traits compared to DZ twins who only share 50% of their genes
Joseph 2004- twin study
meta analysis for all schizophrenia studies prior to 2001 = reliable
found concordance rate for MZ twins was 40.4% and DZ twins 7.4%
issue- twin studies
environmental element is the same and any differences in concordance rates are a product of internal factors
Joseph 2004 evaluates study
identical twins are treated more similarly
extraneous variable environment
Tienari 2000
found the adoptees whose biological mothers had been diagnosed with schizophrenia 6.7% also revived diagnosis compared to 2% of control adoptees born to non schizophrenic mothers
dopamine hypothesis
genetic factors can lead to differences in brain chemistry concluding brain chemistry to be the causal factor for schizophrenia
dopamine hypothesis example
schizophrenia might result from high levels of neurotransmitter dopamine
drug lopa– dopamine hypothesis
increases dopamine levels in those suffering from Parkinson’s disease – can produce side effects such as schizophrenia
supporting evidence for dopamine hypothesis
post mortem examination of patients brains showed they had greater density of dopamine receptors in certain parts compared to those without schizophrenia
