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SchizophreniaFeatures:Schizophrenia is found universally at a rate of about 1.4-4.6 per 1000 people. About a quarter of people who have had schizophrenia recover and don’t relapse. About a quarter of people who have schizophrenia never recover. That leaves 50% who have periods of recovery and periods of symptoms. The positive symptoms can be overcome, but negative symptoms and tend to remain.Positive Symptoms:Positive symptoms are about changes in thinking in the person. These include:Hallucinations – seeing or hearing things that aren’t there. Hearing voices in some cultures is not seen as a sign of mental disorder, but of a personal spiritual capability. In these cases, the voices are often kind and positive, whereas with schizophrenia the voices are often harsh and critical. Critical voices provide a running commentary on what the person is doing. Tells the person what to do – usually uncharacteristic acts.Delusions – false beliefs. Such as someone thinking their movements are being controlled nu someone else. A common form of delusion is the paranoid delusion; the sufferer believes that someone is trying to mislead, manipulate or even kill them. Someone suffers from delusions of grandeur when they think they are in a prominent position of power, such as a King, or that they possess special power, such as the cure to cancer. Delusions can also take the form of the person thinking that unrelated things are in fact intended to relate to them, they may feel that a newspaper headline carries a secret message for them. Delusions can lead to strange behaviour such as covering windows to shut out the sound of God.Thought disorders – makes a person’s speech hard to follow. They might also lose concentration at work or complain of having muddled thinking. The person may become disorganised. Further developments of thought disorders are ‘thought insertion’ (a person thinks their own thoughts are put there by someone else) or ‘thought broadcasting’ (thinking others can hear their thoughts).Evaluation: Positive symptoms tend to have greater weight when diagnosing schizophrenia but, as was explained earlier, they can be affected by cultural differences so perhaps should not be weighted as strongly as negative symptoms, which might be more objectively measured.Negative Symptoms:Negative symptoms often start before positive ones, sometimes years before schizophrenia is diagnosed. This is known as the prodromal period. They include:Lack of energy and apathy – for example, no motivation to do daily chores.Social withdrawal – for example, avoiding family and friends and not going out.Flatness of emotions, where the face becomes emotionless and the voice dull with no rise and fall.Not looking after appearance and self, and generally not adhering to expectations with regard to preserving a sense of self.Evaluation: Negative symptoms seem less affected by cultural factors and it has been suggested that they can be more objectively measured. Hearing voices, for example, is hard if not impossible to measure. Lack of energy, flatness of emotions or social withdrawal might be more easily monitored. Prodromal features have been found to be present in many adolescents and cannot be taken to indicate the onset of schizophrenia.Types of Schizophrenia:Paranoid: someone being suspicious of others and having delusions of grandeur, often hallucinations.Disorganised: disorganised, hard to follow speech, inappropriate mood for situation.Catatonic: when someone is very withdrawn and isolated and has little physical movement.Residual: where there are low level positive symptoms but psychotic symptoms are present.Undifferentiated: when the person doesn’t fit the other types.Explanation BIOLOGICALDopamine hypothesisExcess of the neurotransmitter dopamine possibly causes schizophrenia. The presence of an excess number of dopamine receptors at the synapses causes the symptoms. It explains why hallucinations may occur as the brain is too active. It is possible that the increase in dopamine in one site of the brain (mesolimbic pathway) contributes to positive symptoms and in another site (mesocortical pathway) to negative symptoms. It suggests a strong genetic link and allows antipsychotic drugs such as chlorpromazine to be used to reduce schizophrenic symptoms. Also, it explains (PET scan evidence) why schizophrenics have enlarged ventricles compared to non-sufferers and smaller frontal lobes (development of the receptors in one area might inhibit their development in another).Evidence: Randrup & Munkvad (1996)Randrup & Munkvad aimed to see whether schizophrenia-like symptoms could be induced in non-human animals by giving them amphetamines. Amphetamines worsen schizophrenic-like symptoms by releasing dopamine at the central synapses. The procedure involved injecting rats with doses of amphetamines. They reported all the known symptoms of schizophrenia were found. They concluded the experiment with a number of different animals, including dogs, cats, pigeons, pigs and squirrels, all showing that stereotypical schizophrenic activity can be produced by amphetamines. This supports the theory that dopamine contributes to schizophrenia.EvaluationAntipsychotic drugs, like chlorpromazine, block post-synaptic receptor sites. If the receptors are blocked, then less dopamine will be taken up so the effects of dopamine are reduced symptoms of schizophrenia are alleviated.Drugs given to increase dopamine production in sufferers from Parkinson’s disease can experience symptoms of schizophrenia, therefore dopamine relates to schizophrenic symptoms. PET scans have shown that genes linked with dopamine production are found with greater frequency in those with schizophrenia.The brains of those with schizophrenia seem to be different, e.g. grey matter differences in the front and temporal lobes. Such brain changes, at an early age, link with sensitivity to dopamine.PET scans show that blocking dopamine receptors doesn’t always remove schizophrenic symptoms. However, if antipsychotic drugs are administered early on in the disorder, then more than 90% of patients respond.Blocking dopamine receptors happens almost immediately but effects aren’t noticed for several days. This suggests that something other than excess dopamine is causing the psychotic symptoms.Amphetamines (cause excess dopamine, resulting in psychosis symptoms) only produce positive symptoms of schizophrenia, which suggests that the dopamine hypothesis is not a sufficient explanation.Social and environmental factors seem to trigger schizophrenia, so a biological explanation is not sufficient. Perhaps stressful events in life can trigger production of excess dopamine.Research Methods (AO3)Evidence also comes from unrelated events, such as how medication affects those with Parkinson’s disease or how using recreational drugs leads to psychotic symptoms.Dopamine receptors are implicated in many different studies, which tends to give the hypothesis reliability.‘Biological’ research methods such as PET scans and animal studies have good controls and have qualitative data (scientific) which means the findings are credible.Something else to do with schizophrenia may have caused the differences in dopamine receptors, rather than dopamine receptor differences causing schizophrenia.Animals are used to investigate dopamine pathways and the effects of drugs on them. Findings from animal studies can’t legitimately be generalised to humans because there are differences in animal brains and the functioning of their nervous systems.The Stress-Diathesis Model suggests that behaviour comes in part from a genetic predisposition and in part from the environment. Gottesman and Shields thought that particular genes predispose someone to schizophrenia by lowering the threshold for coping with stress. Even if there is a single gene for schizophrenia, their explanation still stands that there is a genetic tendency to schizophrenia that can be triggered by environmental factors.Another Biological explanation is the genetic one - Gottesman and Shields ( 1966)Treatment BIOLOGICAL Drug TherapyDrug treatment was first introduced in the 1950’s and can be called chemotherapy, which is an overall term for therapy using chemicals. A patient is only put on one antipsychotic drug at a time. However, antidepressants can be used at the same time and anticonvulsants might also be prescribed. If dopamine is linked to schizophrenia, then drugs that target dopamine transmission should reduce the symptoms of schizophrenia, e.g. Chlorpromazine acts by blocking dopamine receptors and therefore reducing its effects. Antipsychotic drugs are used to treat schizophrenia and suppress hallucinations and delusions. There are two types of drugs; ‘typical’ ones which are well established and ‘atypical’ which are less widely used but have fewer side-effects and act in different ways to ‘typical’ antipsychotic drugs. Symptoms of typical drugs:Sleepiness and tiredness;Shaking and muscle spasms;Low blood pressure;Problems with sex drive;Weight gain.Evidence: Meltzer et al. (2004)Meltzer carried out studies to look at the use of drug therapy on schizophrenia patients. He chose 481 patients with schizophrenia and randomly assigned them to groups. The groups had either a placebo, 4 investigational drugs (new antipsychotic drugs) or a Haloperidol (established antipsychotic drug) for 6 weeks. The study gathered information about positive and negative symptoms, severity of the illness and a score from the psychiatric rating scale. Haloperidol gave significant improvements in all aspects of functioning tested compared with the placebo group so the study appeared to have validity. Two of the new drugs also showed improvements in several of the measures compared with the placebo. The other 2 new drugs showed no improvements.Meltzer concluded that Haloperidol improves symptoms of schizophrenia and that drug therapy does work to an extent.EvaluationDrugs are thought to be better than pre-1950’s treatments as they are seen as more ethical and more effective.Drug treatment rests on strong biological evidence about the causes of schizophrenia so is underpinned by theory which helps in considering its effectiveness.It’s cheap, ethical and practical to give people drugs.Schizophrenic patients don’t continue to take the drugs prescribed (in 50% of cases). It might be that problems in functioning means they might find the side-effects too uncomfortable or forget.Rosenhan found that patients in institutions preferred to hide their drugs rather than take them.Drugs have been called a ‘chemical straight jacket’ and some people think that such control by society is unacceptable and unethical.Antipsychotic drugs have side effects and aren’t a ‘cure-all’ treatment as they don’t cure negative symptoms of schizophrenia.Drugs don’t take into account a patients environmental or social problems which might contribute to relapses. Social treatments such as ACT programmes address these issues.Research Method TWIN STUDIESThis method involves comparing MZ (monozygotic) and DZ (dizygotic) twins to see what differences there are in the incidence of certain characteristics. MZ twins are genetically identical and share 100% of their genes as they come from one egg. DZ twins only share 50% of their genes as they come from two eggs. If a characteristic is completely genetically given (nature), MZ twins would both show characteristics. If a characteristic comes from environmental influences and factures (nurture), then MZ twins will not share the characteristic any more than DZ twins. With regard to schizophrenia, if one twin has the disorder and the condition is inherited it would be expected that both MZ twins would have the disorder. With DZ twins, there is only a 50% chance both twins would inherit schizophrenia.EvaluationThere is no other way to study genetic influences so clearly because no other humans share 100% of their DNA.Although the amount of DNA they share differs, both MZ and DZ twins share their environments, so there is a natural control over environmental effects.MZ twins share their DNA but even in the womb they may experience different environments which may lead them to develop differently.MZ twins may be treated more alike than DZ twins because they are identical and share their gender too, so their environments may not be as controlled as initially thought.Evidence: Gottesman and Shields (1966)Aim: The aim was to investigate the relationship between genetic make-up and schizophrenia, by looking at whether twins of schizophrenic parents to see if they develop the disorder.Procedure: 57 pairs of MZ and DZ twins were studied where at least one of the twin pair had been hospitalised and diagnosed with schizophrenia. The question was, when one twin had developed schizophrenia, was the other also diagnosed with schizophrenia, and whether they were MZ or DZ twins. G&S looked at the concordance rate within MZ twins to see in what percentage of cases when one twin was diagnosed with schizophrenia, the other one was too. The same was done for DZ twins.Results:The results showed that schizophrenia is on average 47% genetic (nature) as when schizophrenia occurred in one MZ twin, there was a 47% chance of it occurring in the other twin. However, when it occurs in a DZ twin, the concordance rate only averaged at 17%.Conclusion:There appears to be a genetic component (nature) in the development of schizophrenia. However, as the concordance rate is not 100% for MZ twins, who are genetically identical, there must be an environmental influence (nurture) on the development of schizophrenia (diathesis-stress model).EvaluationThe study replicates other studies and the results are backed up by them which means they are likely to be reliable.It addresses criticisms of previous studies by detailing the sampling carefully so that it was understood which twins were included and why. This shows good controls.A concordance rate simply notes whether if one twin had an abnormality, the other has it too. It would have been more useful to information on the degree of schizophrenia of both twins.There might be different forms of schizophrenia and that some of the disorders diagnosed might come from life experiences rather than genes. Reasons for schizophrenia weren’t distinguished.KEY STUDY 1Rosenhan 1973 – Being sane in an insane placeBackgroundInterested in defining abnormality, mental disorders and problems with ‘sane’ and ‘insane’.The DSM offers lists of symptoms which help to distinguish between ‘sane’ and ‘insane’. However Rosenhan wanted to investigate the use of the DSM, as he felt there were issues with the RELIABILITY and VALIDITY, as well as defining ‘abnormality’.Placed ‘normal’ people, with no history of psychiatric disorder, into an institution to see if they could be distinguished from ‘the insane context in which they are found’.AimTo see if 8 sane people who gained admission into 12 different hospitals would be ‘found out’ as sane.To find experience being in an institute and what it feels like to be viewed as ‘insane’.ProcedureStudy 1Eight pseudo-patients. 3 women and 5 men. Rosenhan was a pseudo-patient.A graduate, a paediatrician, a psychiatrist, a painter, a housewife and 3 psychologists.Used pseudonyms and provided different occupations to avoid being treated differently.12 hospitals in 5 different states and were varied in character (e.g. old/new, private/public).Called hospital for an appointment. Arrived saying that they had been hearing voices that were unclear but saying ‘empty’, ‘hollow’ or ‘thud’. Other than changing names and some personal history, patients gave details of their own life. Non e of their current behaviours or history was pathological.Once admitted, they stopped simulating symptoms of abnormality – behaved normally. They were given medication (which they didn’t swallow), responded to instructions and chatted to other patients. They had to convince staff they were sane.All but one wanted to be discharged immediately due to stress, therefore behaved ‘sanely’ and were ‘paragons of cooperation’ResultsLabelled schizophrenic.All were admitted and none were detected as being sane. All except one pseudo-patient had a diagnosis of schizophrenia in remission.Between 7-52 days spent in hospital. 19 days average.Hospitals considered good and not to blame for failure to recognise insanity. Patients and visitors felt they were sane: 38/118 patients on admissions ward were suspicious.Rosenhan suggested that doctors are more likely to step on the side of caution. However, psychiatric diagnosis carry stigma, making the implication that misguided psychiatric diagnosis is in some way more serious than medical ones.Staff at a teaching hospital doubted findings of the first study. Rosenhan told them that one or more pseudo-patients would be admitted over a 3 month period.Each staff member was asked to rate patients presenting themselves on a scale of 1-10 reflecting likeliness of being a pseudo-patient.NO GENUINE PSEUDO-PATEIENTS (as far as known).Results193 patients were judged.19 were considered to be pseudo-patients by at least one psychiatrist and one other staff member.Conclusions‘Any diagnostic process that lends itself so readily to massive errors of this sort cannot be reliable’Once labelled schizophrenic, there isn’t much a pseudo-patient can do to overcome the tag.Insanity is a powerful trait and therefore all behaviours and characteristics are coloured by the label ‘insane’, and normal behaviours are thus overlooked.Doctors and psychiatrists are more likely to make a type 2 error (diagnosing a healthy person as sick) then a type 1 error (diagnosing a sick person as healthy).EvaluationStrengthsFindings can be generalised due to the variation between hospitals.It is reliable as in all 12 hospitals, the same results were found on replication. It also had standardised procedures.Ecologically valid due to setting. It was a field study.Participant observation had some degree of objectivity.Confidentiality of hospitals and staff kept safe.WeaknessesMay have interpreter bias.Hospital staffs were deceived. They may have left their profession due to doubt in their own diagnosis.Lacks validity as experiences of pseudo-patients may have differed from real patients who didn’t have the comfort of false diagnosis.Only had DSM II in the 1970’s. A more recent study may have led to more reliable diagnosis due to improvements in the DSM.Not a natural setting for pseudo-patients.Optional KEY STUDY Goldstein (1988) – Gender differences in the course of schizophreniaAimTo see if there is any significant difference in the age of onset of schizophrenia between the two sexes.To see if women have a less severe course of the disorder than men.ProcedureThe sample consisted of 199 men and women. In the 1970s all had been diagnosed with schizophrenia on admittance and on discharge from psychiatric hospital, where they had stayed for less than six months. They were all expected to live with a family member, either a parent or a spouse, and all were aged between 18 and 45 years. None of them had any organic brain disorder such as epilepsy, and none had any drug problem, including alcohol abuse.They were re-diagnosed 10 years later using the revised version of DSM. Of the original 199 patients, 169 were re-diagnosed with schizophrenia using the revised version, 30 were deemed to be not schizophrenic according to the revised version of DSM (misdiagnosed). Of the 169 who were re-diagnosed, 52 were first-time admissions and 38 had only one pervious hospitalisation in the 1970s. The remainder were patients studied by Goldstein.How well the patients could function in everyday life was measured by looking at marital status, occupational status, peer relationships, isolation and interests. The course and severity of the illness was measured by looking at the number of times the patients had been in hospital, and how long the hospital stays had been over a 10-year period.ResultsThe researchers found that schizophrenic women had a significantly lower number of re-hospitalisations (average of 1.1 over 10 years) and shorter length of hospital stays (average 207 days over 10 years). Men had 2.2 re-hospitalisations over a 10 year period, with 418 days in hospital on average.The difference in gender was even stronger when looking at a five-year period, possibly because the severity of schizophrenia does not worsen after 5 years.Differences in premorbid functioning, such as isolation, peer relationships and interests, affected re-hospitalisations. Social functioning, such as marital and occupational status, affected the length of stays.ConclusionGender differences in the course of schizophrenia are present in the early stages of the disorder, with poorer premorbid functioning in men being responsible for a poorer outcome.EvaluationStrengthsWhilst this was a longitudinal study, it did not suffer from the problem of participants dropping out, as data on their functioning was collected at the start of the study, and data about their hospitalisation was obtained from the New York State Department of Mental Health.The men and women were well matched in terms of marital status, age, education, religion and socio-economic status.Two experts who didn’t know the aim of the study tested the reliability of the re-diagnosis; there was inter-rater reliability of 80%, showing that there was good reliability.The sample size was 169, as they added people who had previously had one hospital stay before the start of the study to increase the sample so that it was more generalizable to all schizophrenics.The data is objective and unbiased in terms of the number of hospital stays and length of the stays, as it came from an outside agency that accurately recorded these details.WeaknessesWhilst the men and women were matched for employment status, the type of employment varied. The women mostly had clerical or sales jobs or were housewives, whilst the men had more ‘blue collar’ jobs. There were also more unemployed men than women.There are problems with generalising the results, as all the participants returned to their families after hospitalisation. The same results may not be true for schizophrenics who do not return to their families. However, all these patients were in the early stages of schizophrenia at the start of the study and it has been found that the most early-stage schizophrenics do rely on family help after hospitalisation, so this may be in fact representative.Another problem with the sample is that the age limit was 45 years. 9% of schizophrenic women have their first schizophrenic episode after 45 and have more paranoia, whilst very few men do, so this may have biased the sample in favour of finding the gender differences. However, in the current version of DSM, people must be under 45 to be diagnosed with schizophrenia, so those over 45 would be diagnosed with a different disorder.If you argue that DSM is not a valid measurement of mental illness, this brings into question the validity of the diagnosis of schizophrenia. ................
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