biological explanations Flashcards
strength (genetic evidence) : Genetic explanation DW
P: There is strong evidence for genetic vulnerability as an explanation of schizophrenia from many sources.
E: Gottesman showed how genetic similarity and shared risk of schizophrenia are closely related. If an identical twin has schizophrenia there is a 48% chance that the other twin will develop schizophrenia. With dizygotic twins it is 17%.
E: This suggests that genetic factors make some people more vulnerable to developing schizophrenia than others.
I: This therefore supports the role of genetics as a biological explanation for schizophrenia. Also, this means that family members who have schizophrenia can get their family tested to see if they have it which would help early diagnosis and treatment.
strength (adoption evidence): Genetic explanation DW
P: Further evidence for the role of genetics in the development of schizophrenia comes from Tienari et al.
E: They found that children of schizophrenia sufferers are still at a heightened risk of schizophrenia if adopted into families with no history of schizophrenia.
E: This shows that there must be a link in genetics as they haven’t been around the person with schizophrenia which supports the idea that nature has more of a role than nurture in the development of the disorder.
I: Therefore this could result in adoption papers having information regarding their family history of schizophrenia so families can support their child.
limitation (nature vs nurture): Genetic explanation DW
P: It is very difficult to separate out the influence of nature vs nurture
E: Gottesman showed that only 48% of identical twins are proven to have schizophrenia. The fact that the concordance rates are not 100% means that schizophrenia cannot wholly be explained by genes.
E: It could be the similarity of environments that causes schizophrenia, as there is an increased concordance rates for DZ twins compared to siblings.
I: This suggests that the genetic explanation cannot give a full explanation of the disorder and more research into twin studies and genetics need to be done.
limitation (biologically reductionist): Genetic explanation DW
P: the genetic explanation of schizophrenia is biologically reductionist
E: It focuses on the role of genes in the disorder and does not consider “larger” influences like the role of cognitions or the environment in the development of the disorder.
E: This means that the genetic explanation should be more holistic and consider cognitive and environmental factors as just focusing on genes because that’s too simplistic.
I: Therefore more research should be done to address other factors such as stress from parents to increase the internal validity of the explanation
strength (support for the dopamine hypothesis): Neural explanation DW
P: There is support for the involvement of abnormal dopamine functioning in schizophrenia.
E: Curran et al found that dopamine agonists like amphetamines that increase the levels of dopamine make schizophrenia worse and can produce schizophrenia-like symptoms in non-sufferers.
E: The study supports the hyperdopaminergic part of the dopamine hypothesis proving that dopamine levels play an important part in schizophrenia.
I: This increases the validity for the dopamine hypothesis as an explanation for the illness and can lead to drugs being given to patients to reduce the level of dopamine. Families can also test babies for their dopamine levels so early signs can be spotted and treatment can be provided.
strength (further evidence for the involvement of dopamine): Neural explanation DW
P: Further evidence for the involvement of dopamine in schizophrenia comes from Lindstroem et al.
E: They completed a radioactive labeling study and found that the chemicals that are needed to produce dopamine are taken up faster in the brains of schizophrenia sufferers than controls.
E: It shows that an increase in dopamine leads to schizophrenia and it also means that schizophrenia sufferers have an abnormal brain structure.
I: Antipsychotic drugs could be used so that you could lower the receptors so there is less dopamine.
limitation (Correlation-causation): Neural explanation DW
P: One criticism of the neural correlates explanations of schizophrenia is the correlation-causation problem.
E: It is not clear what comes first- are raised dopamine levels the cause of schizophrenia, or is it the raised dopamine level the result of schizophrenia?
E: If we don’t know for certain what comes first then this means the existence of neural correlates in schizophrenia explains very little about the disorder itself.
I: This reduces the internal validity of the neural correlates explanation as it cannot fully explain the cause of schizophrenia limiting its accuracy.
limitation (biologically deterministic): Neural explanation DW
P: Neural correlate explanations of schizophrenia are biologically deterministic
E: It explains schizophrenia in terms of brain structures and neurotransmitters in the brain which we have no control over so our behaviour is determined.
E: It could have the implication that they are going to get schizophrenia regardless which gets rid of free will and control over their action due to the symptoms
I: This could impact their mental health have a negative effect on how they manage their disorder leaving them feeling guilty as they cant help how they behave. It also creates a stigma for schizophrenia which is damaging for sufferers which could even demotivate them to wanting to get treated and manage their symptoms.
