Biological Explanations For Schizophrenia Flashcards
What is one biological explanation of schizophrenia
Genetic factors
What is supporting evidence for genetic factors
family studies, twin studies and adoption studies.
Who studied genetic relatedness
Gottesman
What did Gottesman find about genetic relatedness
children with two schizophrenic parents have a concordance rate of 46%, compared to just 13% concordance rate for a child with only one parents with schizophrenia and 9% for a sibling who has schizophrenia.
What does Gottesman’s research show
that schizophrenia does run in families however it could also be due to common rearing patterns and other non-heredity factors.
How does gottesmans research on genetic relatedness link with expressed emotion
the family could be hostile and this would then increase the chances of an individual becoming schizophrenic.
Who researched schizophrenia in twins
Joseph
What did Joseph find about schizophrenia in twins
monozygotic twins had a 40.4% chance of developing schizophrenia compared to a 7.4% chance for dizygotic twins. Twins environment are equivalent yet monozygotic twins that share 100% of their genes do have a 100% concordance rate
what does Joseph’s research show
that environments do play a significant role in developing schizophrenia as well. This can also be shown through the diathesis stress model.
Who researched adoption studies with schizophrenia
Tieneri et al
What did tierneri et al study and find
164 Finland adoptees and found the biological mothers who had been diagnosed with schizophrenia. 6.7% of their children had also been diagnosed with it, compared to 2% of 197 control adoptees whose biological mothers did not have schizophrenia.
What did the investigators of Tieneri et al’s study conclude
that these findings showed that the genetic liability to schizophrenia had been ‘decisively confirmed’.
Evaluation of the biological approach for schizophrenia
- Another biological explanation
- Mixed evidence for the dopamine hypothesis
- Development of treatments for sz
- Key weaknesses
Evaluation: another biological explanation
Another biological explanation is the dopamine hypothesis which states that schizophrenics have an abnormal amount of D2 receptors so there is more dopamine binding. If there are disturbances with these processors it can lead to attention, perception and thought problems. This evidence that dopamine has a link to schizophrenia comes from amphetamines, anti-psychotic drugs and Parkinson’s disease.
Evaluation: mixed evidence for the dopamine hypothesis
Mixed evidence for the dopamine hypothesis-Dopamine agonists increase the levels of dopamine and make schizophrenia worse and can produce schizophrenia-like symptoms in non-sufferers.Antipsychotic drugs reduce dopamine activity.These suggest an important role of dopamine in schizophrenia .Lindstroem et al found that chemicals needed to produce dopamine are taken up faster in the brains of schizophrenia sufferers than control suggesting that they produce more dopamine.There may be other neurotransmitters involved such as glutamate.