THE CLINICAL APPROACH - SCHIZOPHRENIA Flashcards
(41 cards)
What are some key points about schizophrenia?
Around 1% of the population suffer from schizophrenia
Individuals who develop the symptoms tend to be 16-25
It’s equally prevalent in men and women, although onset is later in women
The peak of onset for men is 16-25 and for women it tends to be 10 years later
Men tend to have a worse prognosis than women
About ⅓ will have repeated episodes, ⅓ will make a full recovery and ⅓ will be untreatable
What did Goldstein find?
that male schizophrenia had twice as many admissions and spent twice as long in hospital than female schizophrenics
What does the DSM V require in order to diagnose schizophrenia?
Two more positive or negative symptoms prevalent for a month or more
General disturbance of 6 months
Cannot be a product of an organic disorder (eg brain tumour) or be on drugs/alcohol
Absence of a mood disorder
What are positive symptoms?
symptoms that one gains in addition to normal functioning
Eg hallucinations, delusions, racing thoughts, paranoid thinking
What are negative symptoms?
symptoms that result in the loss of normal functioning
Eg low motivation, emotional flatness, decreased speech, loss of interest in life (apathy), social withdrawal, decreased sense of purpose
What are cognitive symptoms?
how well the brain uses/stores/learns information
Eg disorganised thinking, slow thinking, poor executive function, difficulty understanding, trouble focusing, anosognosia
What are the key points of the dopamine hypothesis?
Positive schizophrenic symptoms are linked to high levels of dopamine (hyperdopaminergia) in the region called the mesolimbic pathway
Negative schizophrenic symptoms are linked to low levels of dopamine (hypodopaminergia) in the mesocortical pathway
Research by Carlsson et al adds more detail to the hypothesis
What is L-DOPA?
used to treat people with Parkinson’s disease, until the levels of the administered drug are properly established the side effects can produce schizophrenic symptoms as it increases dopamine levels
What did Randrupp and Munkvad do?
Injected laboratory rats with doses of between 1-20mg of amphetamines
Noted that the rats exhibited behaviours associated with schizophrenia, such as aggression, social isolation and stereotypical activity
Repeated the procedure on different species, including chickens, pigeons, cats, dogs, and squires and found similar results
Concluded that some forms of schizophrenic behaviour can be induced by amphetamines as they increase dopamine levels in the brain
What are strengths of the dopamine hypothesis and what are the key names?
Explains both positive and negative symptoms of schizophrenia which gives it explanatory power
Another neurotransmitter - glutamate - is also thought to cause psychotic symptoms if its production is blocked, supporting the role played by neurotransmitters in schizophrenia but rejecting a specifically dopamine explanation
Lieberman et al, Johnstone et al, Lindstroem et al
What did Lieberman et al find?
that 75% of schizophrenic patients show new symptoms or an increase in symptoms when using amphetamines and methylphenidate (drugs that mimic the action of dopamine)
What did Johnstone et al find?
that there are drugs that are effective for treating schizophrenia that are dopamine antagonists
What did Lindstroem find?
performed a PET scan study on 10 untreated patients with schizophrenia and 10 health controls, injected L-DOPA and saw that it was taken up more quickly in the patients with schizophrenia suggesting more dopamine was produced
What are weaknesses of the dopamine hypothesis?
Alpert and Friedhoff found that some patients show no improvement after taking dopamine antagonists
There is no evidence to suggest that clozapine actually increases levels of dopamine in some parts of the brain, presumably as the brain adapts to the antagonist effects of the drug - this contradicting the dopamine hypothesis
Depatie and lal showed that a drug called apomorphine, which acts as a dopamine antagonist (increases the effect) does not induce schizophrenia
Ethical issues in directly testing the dopamine hypothesis as it would involve extracting dopamine from live brains
What is the genetic explanation of schizophrenia?
studied MZ twins and schizophrenia and discovered that MZ twins have a concordance rate of 48% and for DZ twins it was 17% (suggests that genetic factors are strongly implicated in schizophrenia yet not entirely)
Also found that the stronger the genetic connection to a schizophrenic relative, the greater the risk of developing the condition
If both parents have it - 46%, if grandparent has it - 5%
What did Rosenthal find in relation to the genetic explanation of schizophrenia?
Reported on the Genain Girls (quadruplets who all developed schizophrenia but at differing ages and different forms)
They all inherited a predisposition to the disorder, but seemingly had sufficiently different environmental experiences within the family which altered the onset and outcome of the disorder
What are strengths of the genetic explanation of schizophrenia?
Heston studied 47 adults, adopted at birth because their mothers were schizophrenic and compared them to 47 adoptees whose mothers weren’t schizophrenic
10% of adults with schizophrenic adults went on to develop schizophrenia compared to none of the control group
Study by the International schizophrenic consortium 2008 found that schizophrenics are more likely to have structural changes to their genes
Crepsi, Summers and Dorus did a DNA analysis and found 28 separate genes linked to schizophrenia, which provided or conferred linguistic skills and creativity, but most or all of these genes tended to lead to serious mental illnesses
What are weaknesses of the genetic explanation of schizophrenia?
Concordance isn’t 100% so genes cannot be the entire explanation
Around ⅔ of schizophrenics have no schizophrenic relative
Research has failed to isolate a single recessive or dominant gene for schizophrenia (more complex than one gene)
Kelly and Murray argue that there are only weak correlations between variations in particular genes of schizophrenics and non-schizophrenics which suggests that there are actually a number of genes involved in the development of schizophrenia
Genes may simply give someone a predisposition to schizophrenia but not an inevitability
There are alternative explanations - eg neurological, neurochemical, psychodynamic, cognitive, social etc
What is the social explanation of schizophrenia?
Argues that the human world acts as a major cause of schizophrenia or at least precipitates relapse in those who are already diagnosed
Fits with the diathesis stress model of mental illnesses, as it argues that it is a combination of biological and environmental factors that causes mental health disorders
Urbanicity, social drift, socio-economic status, immigration and minority status,
How can urbanicity lead to schizophrenia?
Living in an urban, densely populated, working class area can be stressful and this stress itself may be the cause of schizophrenia
Urban living is often associated with social deprivation, high unemployment and poverty, poor housing, social isolation, high rates of crime and drug use, separation from parents and hold a low status
This factors all contribute to a high level of psychological distress, leading to a schizophrenic breakdown in people who are vulnerable
Eaton found that living in a city exposed people to more long term stress such as exposure to noise, light pollution, criminality, faster pace of living and greater anonymity
Life can be more competitive in a densely populated city, this can increase the feeling of social defeat which is a stressor that can lead to schizophrenic symptoms
How can social drift lead to schizophrenia?
Individuals struggling with stress are more likely to withdraw fro society
Less likely than other people to spot their unusual thinking and behaviour
This allows space for abnormal thinking to develop and therefore they begin to behave strangely
People with schizophrenia may find it difficult to maintain high powered jobs and dynamic lifestyles and so drift down the socio-economic scale
Schwartz found that schizophrenics were downwardly mobile, supporting the social drift theory
How does socio-economic status lead to schizophrenia?
Some children grow up in environments that are less favourable than others where their needs aren’t met and this can make them more vulnerable to mental health disorders
For example, families affected by unemployment, poverty, and a poorer standard of living may be exposed to considerable more stress
Cooper using five categories of social class found that for single men, the rate of schizophrenia in social class 5 (unskilled labourers) was 4.1x higher than those in class 1
How can immigration and minority status lead to schizophrenia?
There are higher rates of schizophrenia in the 1st and 2ns generation immigrants than there are in indigenous populations (higher in 2nd generation)
Although it appears that minority or out group status is the key, the marginalisation of people leaves them vulnerable to schizophrenia
The higher rates in the 2nd generation can be explained by them developing a weaker ethnic identity than their parent as they have learnt more than their parents of the culture they live in so fit into the norms of society (identification with their family is at odds and can create stress)
Immigration populations tend to be disadvantaged with regard to educational attainment, social class, standard of housing and discrimination and also tend to live in over crowded conditions
White people from lower SES groups don’t have the same increased risk as black immigrants, suggesting it is more than simply social diversity and lower SES that causes schizophrenia, it is also experiencing discrimination
Brown found than when immigrants lived in neighbourhoods where their own ethnic group did not predominate there was a higher rate of psychotic disorders compared to neighbourhoods where they did
What are strengths of the social explanation of schizophrenia and what are the key names?
Can help deal with schizophrenia by drawing attention to factors which affect mental health at the community level
Housing projects which reduce overcrowding and encourage neighbourhood cohesion and celebrate cultural diversity should foster the courage, fortitude and resilience which will help communities arm themselves against mental breakdown
Evangelos Vassos et al, Veling et al