PSU2003 W1 Schizophrenia 1 - (L) Flashcards
What are the general symptoms of Schizophrenia ?
Auditory/visual hallucination (prolonged periods), cogntiive problems, negative effects, mania, disorganised speech, delusions, paranoid, grandiose, persecution, inappropriate affect odd behaviour.
What are some of the historical perspectives on the causes of Schizophrenia ?
R.D. Laing (linked familial dynamics as the reason for schizophrenia but had no control condition) Freud (paranoid delusion sresult from repressed sexual urges which are striving for expression)
What are the limitation of these historical perspectives?
They lack evidence, R.D. Laing had no control condition and Freud did not use evidence
Explain the possible influence of genetics to the development of schizophrenia?
The concordance rate for schizophrenia is higher in monozygotic twins (45ù) compared to dizygotic (10%) this could show a genetic predisposition to schizophrenia.
Explain is the possible influence of the Environement to the development of schizophrenia?
The concordance rates are to low to be the sole factor, exposure to stressors is common ebfore an episode and the severity of the episode can be predicted by the amount of stress.
What are the main pharmacological treatments of schizophrenia?
Chlorpromazine and Reserpine, both discovered through luck
What is the dopamine theory of schizophrenia?
The thoery believes schizophrenic people have more D2 receptors which leads to more dopamine within the synaptic cleft, which leads to the positive symptoms (mania)
What is the etymology of Schizophrenia?
“A splitting of the mind”, skhizein “to split” and phren “heart, mind” Originally thought to be a breakdown of integration between emotion, thought and action.
What were R.D. Laing’s thoughts on schizophrenia?
Linked familial dynamics as the reason for schizophrenia but he had no control condition. [he did not believe schizophrenia was an illness he viewed it more as a way people cope with chaotic environments.]
Was R.D Laing correct (even thought he didn’t have a control condition)?
He was partially correct as environment does play a factor however it is not the sole cause.
What was Freud’s belief?
believed that “paranoid delusions result from repressed sexual urges which are striving for expression.” – no evidence
What are the concordance rates for Dizygotic and Monozygotic twins for schizophrenia?
45% and 10%
How were anti-psychotic drugs discovered?
Luck
How was Chlorpromazine discovered?
originally marketed as an antihistamine (used to treat fevers/allergies as an anti-inflammatory). French surgeon noticed it calmed normal patients when used as anti-inflammatory. Decided it might calm schizophrenics and it did
How was Reserpine discovered?
Taken from snale root plant to treat mental illness in india, also effective in treating schizophrenia.
What are the similarities between Chlorpromazine and Reserpine?
Both take 2-3 week sto work, symptoms like those in parkinsons start to emerge (loss of dopamine)
What role / How do these drugs work?
The drugs blcok dopamine which affects the substantia nigra (bring dopamine to emotion snad motor areas)
What is Chlorpromazine’s mode of action?
It blocks DA receptors and stops DA working, as they cannot bind to the receptors, this is done by a false transmitter (antagonsit)
What is Reserpine’s mode of action?
It deplete vesicles (pops them), reducing the amount fo DA that is released.
What is the dopamine hypothesis?
Drugs that reduce dopamine neurotransimmision reduce psychotic symptoms. Drugs that increase DA neurotransmission, produce psychotic symotoms, this led to the dopamien theory of schizophrenia.
What other drugs provide evidence for the dopamine hypothesis?
Cocaine psychosis, amphetamine psychosis (drugs that increase dopamine), They blcok the reuptake of dopamine which leaves more in the synaptic cleft, which causes schizophrenic like symptoms
What is Haloperidol?
Is an effective anti-psychotic but isn’t very good at binding to dopamine receptors, becuase there is more than 1 type of DA receptor
What is the role of dopamine receptors in the use of anti-psychotic drugs?
the efficacity of the drugs as a treatment for the symptoms can be prodicted by the efficacity of the drugs in binding to dopamine receptoss.
What are the types of DA receptors?
D1-LIKE (D1;D5) positively coupled to adenlyate cyclase, D2-LIKE (D2;D3;D5) negatively coupled to adenlyate cyclase.
What is a Adenylate cyclase?
Enzyme that helps send messages inside the cells.
What is pharmacological fallacy?
drug treating something, and it works in a certain way doesn’t mean that you had a problem of a reduction of that thing in the first place. But believing that is pharmacological fallacy.
How do PETs work?
Positron emission tomography make something radioactive, injecting it into the blood. It crosses the blood brain barrier into the brain, you then can use a scintillation counter to see where in the brain the radioactivity is and how much there is.
What did Seeman et al. 2000 show?
There is some evidence to suggest that there is an overactive dopamine system in some people with a diagnosis of schizophrenia.
What is the difference between schizophrenic people and the control?
Difference in receptors, greater number of dopamine reeptors in schizophrenic people.
What was a good predictor for how well the antipsychotic medication was going to work?
The number of dopamine receptors, the more receptors the better the treatment would be.
How is stress related to schizophrenia?
exposure to stressors is common before an episode and there is a correlation between the amount of stress and severity of episode
What is an exemple of a specific enironmental stressor linked to schizophrenia?
Bullying expereinces and psychotic expereinces (delusion) in non-schizophrenics