Schizophrenia (Oversimplified prob dont use unless desperate) Flashcards
Schizophrenia
Cause
Genes
Prevalance
The prevalence rate of schizophrenia is 1% of the world’s population
this does not change year to year though
therefore meaning that there is a strong genetic components
As if it was contagious more people would get it but as people are born and die it’s probably genetic
Schizophrenia
Cause
genes
twin studieds
If one twin has schizophrenia does the other one?
well Gottesman and shields 1966 went to find out
Reminder MZ =100% identical
DZ = 50%
57 twin pairs
MZ = 54% shared SZ (Concordance rate)
DZ = 18%
. This therefore shows but it’s not just genetic as MZ would be 100% concordance rate
but it does show there is a large netic and opponent as the concordance rate of MZ twins sharing schizophrenia is greater than DZ twins
Schizophrenia
Cause
Genes
Adoption Studies
Adoptions studies use twins
one has been adopted by someone who is not their biological parent so they grew up in a different environments from which ones their siblimgs did with their bio parents
this is to determin if there is a Nurture factor in SZ
• Kety Et al 1968
33 adopted twins
finds a high concordants rate among adopted twins if one has schizophrenia the other one likely does too
so genetics is still a large influencing factor for SZ than environment
Schizophrenia
Cause genes
Family studies
Family studies of studies but look at the relationships of those with schizophrenia to their parents or relatives that also have it
Kety et al 1986 also did this in their study
They found a higher percentage of family members and relatives also had schizophrenia
This therefore shows that there is a high genetic components in schizophrenia
Schizophrenia
Cause Brain Structure
Ventricles
The ventricles are filled with fluids
In schizophrenia brains there are much larger ventricles than a non schizophrenia brains
therefore an increase amount of brain damage is present in those with schizophrenia
Schizophrenia
Cause brain structure
Pfc
The prefronto Cortex is problem solving the people with schizophrenia has visual damage in the prefrontal cortext compared to non-skits of running people
Schizophrenia
Cause
Brain structure
Visual Cortex
The visual Cortex is located in the back of the brain where the visual functions are done
People with schizophrenia have damage to their visual cortex
SZ people have visual deficits in the way the perceived the world around them
Schizophrenia
Cause Brain structure
Wernicke’s Area
Wernicke’s area is located on the left side of the brain for right-handed people and the overway round for left-handed people
It’s also located within the language area of the brain
in which there are two different pathways to deal with language
what
which allows us to understand what is being said and
where
which allows us to understand where the voices coming from
brains can differentiate between internal and external dialect of those around them
however in schizophrenic brains this not so easily done
which is why they have internal conversations but perceive it as an external one
which results in auditory hallucinations
A symptom of schizophrenia
Schizophrenia
Cause
Neurotransmitters
Dopamime
Dopamine is active in excess in certain parts of the schizophrenic brain
This is linked to one kind of dopamine receptor which receives dopamine and causes it to be active this is called the D2 receptor
The malfunction of this means that dopamine works for longer in excess which causes the cognitive systems to function incorrectly
This was first discovered in 1950 when a drug was used up to effectively treating psychosis
including SZ which affected the dopamine system in the brain
so they found that a system of dopamine causes the issue of SZ
Schizophrenia
Cause NT
Glutamate
And large amount of glutamate acts to regulate the amount / function of dopamine
If there is an issue with glutamate it may lead to the dopamine issue that causes schizophrenic symptoms such as the cognitive systems to incorrectly function
Schizophrenia
Cause NT
Serotonin
Serotonin activity in excess in certain parts of the brain may cause the kind of negative symptoms of schizophrenia for example their flattened effect
similar to some forms of depression
Schizophrenia
First generation drugs
First generation drugs are typical antipsychotics
which are used to primarily treat positive symptoms such as hallucinations and delusions
Schizophrenia
Second generation drugs
These are atypical antipsychotics
they also are effective at treating positive symptoms but they are more effective than the first gen drugs at treating negative symptoms
Sutch as a lack of ordinary mental activities such as emotional expression, social engagment, thinking and motivation
Schizophrenia
Chloroplosamine
1st gen
Est. 1953
It reduces the symptoms of SZ such as hallucinations
It works by dampening the effect of dopamene and reducing its activity in all of the brain
A major side effects of this is that dopamine also controls motor movements in the brain so by decreasing dopamine you decrease the motor movements
Two little dopeamine leads to Parkinson’s Disease which involves muscle stiffness
As in SZ only some parts of the brain have excess dopamine that means by reducing all of it in the brain it leads to major motorc side effects
such as unusual, slow, a lack of and uncontrollable movement in the body
Due to this major side effect on motor movements it led to patients being reluctant to take it
Other side effects included possible seizures
Schizophrenia
Haloperidol 1st gen
Introduced in 1967
It was far more Potent than chloropromazine meaning that it was only needed in smaller doses
which meant that it had a less overall effect on motor movement but it was still quite high
It was effective at stopping auditory hallucinations
This works by dampening dopamines affects
Motor movments side effects are still severe including slow, unusual ,a lack of and uncontrollable movements in the body
Other side effects include the feeling sleepy, Insomnia, dizziness, dry mouth, constipation and Blury vision
Schizophrenia
Clozapine
2nd gen
Introduced in 1990 it was a second generation drug
which decreased the motor movment side effects so more patients were willing to take them
but it also increased psychosis treatment
Decrease hallucinations and delusions which worked by inhibiting D2 dopamine receptors
Side effects
Causes potential issues / risks of agranulocytosis
( decreased white blood cell efficiency)
Therefore it weakens the immune system and increases the risk of infection and disease
This meant that patients that were given it needed Close monitoring to see if they were developing this so they could treat it
which was impractical
Schizophrenia
Olanzapine
Second gen
Lanzapine was introduced in 1991 in the United States of America and in 1996 in use for general medication
It had very good effect ( at reducing the positive symptoms of SZ)
in the early stages of psychosis such as after their first psychotic episode
This LED the moral question on should you give drugs to somebody who is a relative of someone SZ due to the genetic factor and therefore at risk of getting it
Even if they have not had their first psychotic episode yet so we can’t confirm if they will develop it or not
This works by blocking dopamine receptors in the brain and it affects serotonin by rebalancing it so behavior can be improved
Side effects include:
Changes in Vision (blur)
Balance and walking changes increasing clumsiness and dizziness
Schizophrenia
Aripiprazole
3rd gen
Aripiprazole was introduced in 2002 and the worked to reduce hallucinations in SZ patients
It works as a partial agonist
an Dopamine Agonist means that it does the same function as normal dopeamine
the Partial means:
when a molecule of ari attaches to a D2 dopamine receptor it does only PART of dopamine’s normal job
Therefore the part of the molecule that that’s working will be able to control motor functions
and the parts that is not working will be in the areas of the brain that has excess dopamine activity therefore reducing hallucinations
(as its not active)
side effects include
Light-headedness, stomach pains, anxiousness, constipation, feeling sick, sleep trouble, blurry vision
Schizophrenia
Strengths that drugs are successful in treating SZ
• all afformentioned drugs treat hallucinations and other effects very well
• second generation drugs have more effective psychosis treatments and less severe motorcycle effects so patients are more likely to take them
• Aripiprazole has less side effects as it is a partial agonist so there is more treatment of hallucinations and less motor side effects meaning that it is very ethical and more likely to be used in the medical field
• olanzapine is a good treatment at early stages of psychosis and maybe even be able to treat people who are only at risk of developing schizophrenia
so it may be able to use the used to reduce the chances of SZ occurring/ developing in the first place
Schizophrenia
weaknesses that drugs are successfull at treating SZ
• first gen drugs have severe motor side effects ( muccle stiffness/unresponsivness) similar to Parkinson’s Disease this also leads to a patient reluctant to take them
• most of the affirmation drugs have side effects: on vision, sleep, dizziness, constipation and anxiousness
• using olanzapine to treat early stages of psychosis raises a moral issue as they’ve not yet had a psychotic episode yet
so to treat someone that does not have any symptoms means that they are just giving them the drug side effects
and the drug could be used on someone who was actually shown a psychotic episode
• arapitrazole deal has minus side effects such as light-headedness, blurry vision, anxiousness and constipation, therefore despite being a drug used in the medical field it is not Flawless
• chloroprozenine and Haloperidol
Have major motorcycle effects such as muscle stiffness, unresponsiveness, slow, uncontrollable movements etc and were the only medication for SZ from 1953 to 1990 over the space of 37 years
And chloropamine also had side effects of possible seizures
So aripiprazole maybe good but it is only a recent development and many had to deal with the major motor side effects in first gen drugs if they didn’t simply refuse them
