Medical Models + Treatment Flashcards
What is the biochemical explanation
Dopamine hypothesis
Outline the biochemical explanation (5) of scz
Imbalance of neurotransmitters called dopamine
Dopamine enhances feelings of arousal rewards and motivation
In the pre frontal cortex there is low levels of dopamine due to low levels of D1 receptors which leads to negative symptoms like low moods and loss of appetite
In ventral striatum there is excess D2 receptors so there in increased dopamine which leads to positive symptoms like hallucination s, relations and disorganised speech and behaviour
What are 3 evidences for the dopamine hypothesis
Drug research - amphetamines and cocaine etc increase levels of dopamine and that’s why it leads to symptoms that resembles psychosis
Post mortem Brian scans of people wit sz shows they higher density of d2 receptors than neuro typical brains
Drug levodopa used to treats Parkinson’s disease enhances dopamine and patients experience psychotic side effects mimicking sz symptoms
What is an example of a biological treatment
Drugs
Specifically clozapine used for schizophrenia
How does clozapine works as treatment for scz
Atypical antipsychotic drug
It binds to the D2 dopamine receptors tk block dopamine being absorbed by the brain to reduce positive symptoms
They only temporarily occupy the dopamine receptors so that there a less movement side effects
Clozapine however also affects 4 other receptors like serotonin and histamines
What is the other type of antipsychotic drug
Typical drugs - permanently binds to d2 receptors which stops dopamine entering synapses permanently
But has many side effects incoming movement - uncontrolled movements and tremors
What are 3 strengths of biological treatment
It is effective treatment - study shown its top 3 most effective treatment for reducing a relapse un cohort study of 290000 patients
It is effective on patients who have been resistant to other medications - (30% bi relief from 3 other antipsychotics, only 4% for clozapine)
Less movement side effects than anti psychotic drugs
What are 3 weaknesses of biological treatment
Side effects like tremors, muscle spasms
Cateful monitoring of blood cell count - life threatening reductions in 1-2% of patents weakness immune system so need regular blood testing
Ethical issues - sometimes sued without consent when patients highly disturbed pose threat to themselves and others
What is the brain abnormality explanation of mental illness
Mental illness caused by differences in brain structure
Outline the brain abonormality explanation of mental illness
Mental illness is caused by differences in brain structure
People with scz have large ventricles (fluid culled cavities ) so those with scz have lighter brains - research by swayze support this
People with scz have smaller nucleus accummbens and larger palladium which are part of reward circuit
Smaller amygdala and hippocampus linked to learning and memory
But large verticals can be linked to anti psychotic drugs (beng choon ho)
What 2 resrwcah support the brain abnormality explanation
What goes against it
Swayze and van erp
Beng Choon Ho
What was swayze study
Swayze reviewed 50 studies of sz and found that many had abnormally large amounts of liquid n ventricles of Brian
What is study by van erp
Analysed mri scan of Brian of 2028 scz patients and 2540 health controls
Those with scz had smaller hippocampus and amygdala - linked to memory and learning
They had larger pallidum and ventricle volumes - linked to rewards circuit
What is study by beng choon ho
Larger ventricles actually linked to anti psychotic medicine which is what makes the ventricles larger
What was the aim of gottesman study
To determine the risk of offspring receiving a diagnosis of schizophrenia, bipolar disorder, depression or any other diagnosis from parents who both have a diagnosis of schizophrenia or bipolar disorder
What was the design of gottesman
National register based cohort study
What was the sample
2.7 million people born in Denmark
Alive in 1968 or born later than 1968 with register link to their mother and father and aged 10 or older in 2007
What were the 2 sources of data - gottesman
The danish civil registration system - info of all people born between (1968 and 1997 is what they were interest in)
The danish psychiatric central register - all psychiatric admission in Denmark from 1970 to 2007 (icd8 and icd10)
What was the procedure of gottesman
Data of the children linked with the parents psychiatric history
Using civil register they identified parents to see if they were also on psychiatric register
Using psychiatric register identified anyone with diagnosis of bipolar or scz or depression
What are 3 results from gottesman
2 parents with schizophrenia - 67.5% chance of any disorder or 27.3% or scz
1 parents with schizophrenia, 7% chance of child with scz
No partners with disorder - only 0.86% chance scz
Outline the genetic explanation of mental illness
We inherit characteristic from our parents - 23 pairs of chromosomes and one form each pair from each parents
Chromosomes have the genes and there are different forms the the same gene - alleles
These genes can explain mental illness inherited
Supporting study - gottesman family studies
And twin studies by hilker
Who was the twin studies by and what did they outline (results )
Hilker
Based on danish twin registry and danish paychiatrix
With monozygotic twins Concordance rate of sz is33%
And 7% in dyzigotic
