Schizophrenia: Biological Explanations of Schizophrenia - Genetics/Neural Correlates/Dopamine Hypothesis (KR) Flashcards
What does the biological explanation assume about SZ?
it is caused by physical factors of the body
How does the genetic explanation explain sz?
SZ is hereditary and is passed through genes
What are our genes?
genetic material that make up who we are
What is meant by genetic predisposition?
based on our genetic material, the likelihood of developing a disorder
What is the term used to describe the likelihood of developing a disorder from our genes?
genetic predisposition
If we have a genetic disposition to Sz what does that mean?
we are more likely to develop Sz
Sz is described as polygenic what does this mean?
Polygenic: multiple genes involved in the development of a disorder
Sz is polygenic meaning that there are multiple genes involved in the development of Sz, What do we call these genes
Maladaptive Candidate genes
give an example of a maladaptive candidate gene involved in Sz
PCM1
if Sz is polygenic, what does that mean for an individuals vulnerability?
it increases and individuals vulnerability
Why does polygenic mean that an individuals vulnerability is increased?
The more maladaptive genes an individual
What have studies shown about the genetic variations for Sz?
there are 108 separate genetic variations
What is meant by a concordance rate?
it is the probability rate
What was the concordance rate found by Gottesman in MZ and DZ twins?
Mz: 48%
Dz: 17%
What does the differences between the Mz and DZ concordance rate show us about the genetic link in SZ?
Closer the genetic link, the higher the probability
What is meant by an MZ twin?
monozygotic: they share 100% of their genetic information
What is meant by an DZ twin?
Dizygotic: they share 50% of their genetic information
What is meant by neural correlates?
Abnormalities in the structure and function of the brain
What are abnormalities in structure and brain function also refered to as?
neural correlates
How are neural correlates identified?
through brain scans
How what abnormality in the structure of the brain associated with SZ?
Enlarged ventricles
What is an enlarged ventricle?
fluid filled spaces in your brain
In a meta analysis by Raz and Raz, What did they find in individuals with SZ in their brain
those with SZ had enlarged ventricles compared to the control group
How are enlarged ventricles associated with SZ?
they are associated with damage to central brain areas and the pre frontal cortex
If enlarged ventricles are damaging the central areas of the brain and the pre frontal cortex, what symptoms does this lead to in SZ?
Negative symptoms such as avolition
What is the dopamine hypothesis?
The idea that neurotransmitters work differently in those with SZ
What is a neurotransmitter?
a chemical messenger in the brain
How is dopamine involved in SZ?
either too much/too little dopamine activity in the brain
What are the receptors in the brain called that process dopamine?
D2 receptors
D2 receptors process what neurotransmitter?
dopamine
What is meant by HYPERdopaminergia?
increase in dopamine activity
What is meant by HYPOdopaminergia?
decrease in dopamine activity
What is the term for increased dopamine activity
Hyperdopaminergia
What is the term for decreased dopamine activity
Hypodopaminergia
What happens when there is increased dopamine activity in the subcortex of the brain?
High dopamine activity in central areas such as Broca’s is associated with auditory hallucinations
Explain auditory halluncinations using the dopamine hypothesis
High dopamine activity in central areas of the brain such as Broca’s areas
What happens when there is decreased dopamine activity in the cortex?
low dopamine activity in the prefrontal cortex is associated with avolition
Explain avolition using the dopamine hypothesis
low dopamine activity in the prefrontal cortex is associated with avolition
What is the term for high dopamine activity in the subcortex?
Subcortical hyperdopaminergia
What is the term for low dopamine activity in the cortex
Cortical hypodopaminergia
