Transcript genetic explanation of schiz ppt

Schizophrenia
True/False
• 3% of the population suffer from
schizophrenia
• The word schizophrenia means ‘split mind’
• The DVM is used to diagnose schizophrenia
• A delusion is a positive symptom
• The symptoms must persist for one year in
order to be diagnosed as schizophrenic
• The flattening of emotion is a positive
symptom
LEARNING Objectives
OBJECTIVES
Learning
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describe the role of genetics in schizophrenia
describe family, twin and adoption studies
which study the role of genetics in
schizophrenia
explain how family, twin and adoption studies
support the genetic explanation of
schizophrenia
Biological V Psychological
Nature V Nurture
Biological Explanations
 Genetics
 Biochemistry
 Brain Structure
Graph Activity
RESEARCH Studies
STUDIES
Research
• What is the logic behind conducting twin
studies?
• What is the logic behind conducting adoption
studies?
TASK
 Complete twin and adoption
recap task
Overview
Overview
• Genetic explanation state that the genes for schizophrenia are
inherited which could be the reason for some symptoms
• It is thought that the presence of certain types of genetic
mutations may be necessary for the disorder to be triggered –
i.e. predisposed to the disorder
• These genes can cause critical neural pathways in the brain to
be disrupted or damaged
• Therefore behaviour that is controlled by these pathways will
not occur or even develop properly
• It is also possible that it is genetics that cause excess
production of/sensitivity to dopamine… this leads us to the
Dopamine Hypothesis ….
AO2/AO3AO2
questions
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What should concordance be for MZ twins if genetics was the only
explanation?
Is there another explanation for high concordance amongst family
members, particularly identical twins?
Why is concordance for MZ twins always higher than that for DZ
twins?
What is the problem with retrospective data?
If diagnostic criteria has changed over time how will it affect the
research findings?
Read over Gottesman & Shields (1966) and complete pgs 20-22
in your packs