Download Assumptions made by the biological model (medical model) about

Evidence supporting the assumptions of the biological approach
Evidence: Barr et al (1990) found that there was increased incidence of schizophrenia in people whose
mothers had flu while pregnant; not all people whose mothers have flu while pregnant develop the
disorder.
Which assumption this tests:
Problems with the evidence that affect how it supports the assumption:
Twin studies: monozygotic (MZ) twins – identical twins – have identical genes while dizygotic (DZ) twins
have non-identical genes. Gottesman (1991) found that there was a 48% concordance rate (agreement
rate) for depression for MZ twins and a 17% concordance for DZ twins.
Which assumption this tests:
Problems with the evidence that affect how it supports the assumption
Research shows that schizophrenics who have negative symptoms (a lack of something e.g. movement)
have larger ventricles (gaps) in the brain than a control group.
Which assumption this tests:
Problems with the evidence that affect how it supports the assumption
Schizophrenics have excess dopamine and many people suffering from depression have a lower level of
serotonin in their system. This can be measured in various ways, such as by looking at byproducts of the
neurotransmitter in urine. Alternatively receptor sites on neurons can be shown up by complex brain
scanning (Positron Emission Tomography, PET scans). These receptor sites pick up the neurotransmitter
from the firing neuron; it is possible that the altered levels of neurotransmitters in people with
schizophrenia and depression is linked to a problem with receptors – there may be either too many or too
few of them.
Which assumption this tests:
Problems with the evidence that affect how it supports the assumption