Schizophrenia

• What are weaknesses of the use of antipsychotics

  Side effects.e.g. typical have itchy skin and sleepiness.Antipsychotics mightn't be appropriate for all people as side effects can be very distressing. therefore not ethical
• What are strengths of the use of antipsychotics?

  Research to support.Leuct carried out a meta analysis of relapse rate for antipsychotics and placebos. 64% relapsed on placebo but 27% who remained on their medication.Antipsychotics are effectivehowever 36% didn't relapse showing that there are other factors impactingAntipsychotics improve the life.e.g. minimising symptoms of schizophrenia.Improves the suitability of the drug.Atypical have less side effects.No tardive dyskinesia.Increases the validity.
• What other neurotransmitter does atypical antipsychotics deal with?

  serotonin and they address the negative symptoms
• What is a side effect of atypical antipsychotics?

  Agranulocytosis - reduces white blood cell count
• Why do atypical anti-psychotics cause less extrapyramidal side effects?

  Have little effect on the dopamine systems that control movement
• How do Atypical antipsychotics work?

  The block dopamine receptors temporarily and then rapidly disassociate to to allow for normal dopamine transmission
• Why were atypical antipsychotics developed?

  - Minimise the symptoms

  - improve the effectiveness
• When have atypical antipsychotics been used since?

  1970s
• What are extrapyramidal side effects?

  Ones that effect our movement and are very serious. An example is tardive dyskinesia which is the involuntary movement of the jaw, face and tonge
• What are the side effects of antipsychotics?

  Dizziness, agitation and sleepiness
• How do typical antipsychotics work?

  1) Bind and block dopamine receptors but don't stimulate them

  2) Initially dopamine levels build up but then production is reduced

  3) This normalises neurotransmitters in key areas of the brain by reducing stimulation of the dopamine system

  Therefore reduces positive symptoms
• Give an example of typical antipsychotics?

  Chlorpromazine
• What are the two types of antipsychotics?

  - Typical (traditional)

  - Atypical (newer)
• How do all antipsychotic works?

  By reducing dopaminergic transmission
• What is the medicine used to treat schizophrenia?

  Antipsychotic - tablets, syrup or injection
• Evaluate the neural correlates biological explanation of schizophrenia?

  Research to support grey matter deficits in patients with schizophrenia.Vita found that patients showed significantly grey matter loss over time in frontal, temporal and parietal lobes.Supports the theoryBiological explanation alone is reductionist.Other factors that led to schizophrenia are being ignored.May be better to take an interactionist approach by combining biological and psychological factors such as the diathesis stress model.
• Evaluate the dopamine hypothesis biological explanation of schizophrenia?

  Unable to establish cause and effect.e.g. unclear if increase in dopamine causes schizophrenia or high dopamine is a result of having schizophrenia.Reduces the validity.Evidence from dopamine hypothesis comes from success in drug treatment.e.g. Leucht found that anti-psychotic drugs (which reduce dopamine levels) were significantly more effective than placebo in reducing both positive and negative symptoms.Supports biological explanation
• Evaluate the genetic biological explanation of schizophrenia?

  Strong evidence to support genetic vulnerability leading to schizophrenia.Gottesman.Suggests that the idea that genetic factors make some people much more vulnerable to developing schizophrenia.Additionally concordance rate for siblings was significantly lower than DZ twins implying there is also some environmental factors.
• What is the revised dopamine hypothesis?

  Positive symptoms caused by hyperdomergia (high levels of dopamine in sub cortex)

  Negative symptoms caused by hypodopamergia (low levels in the pre-frontal cortex)
• What else increases dopamine levels in schizophrenics brains?

  - Abnormally high levels of D2 receptors

  - Resulting in more dopamine binding

  This is thought to cause hallucinations and delusions
• What is dopamine like in patients with schizophrenia?

  - Unusually high levels

  - Dopamine fires too easily and too often often
• What effect does dopamine have and what is it associated with?

  - An excitatory effect

  - Associated with the feeling of pleasure
• What has this found?

  People with schizophrenia have reduced grey matter in their pre-frontal cortex. Studies have further found a link between grey matter in pre-frontal cortex and negative symptom severity of schizophrenia

  Additionally!!!

  Patients with schizophrenia have reduced grey matter in the left superior temporal gyrus (contains auditory centres and Wernicke's area) implying its associated with hallucinations and disorganised speech.
• What does the neural correlate suggest?

  Measurements of the structure or function of the brain that occur in conjunction with the characteristic symptoms of schizophrenia and so may have implicated the origins of schizophrenia.
• Additional facts about schizophrenia?

  - Polygenic

  - Research suggests there are 108 genetic variations associated with increase risk of schizophrenia
• What did Gottesman find?

  MZ concordance rate = 48%

  DZ concordance rate = 16%

  Siblings concordance rate = 9%
• Which study supports the idea of schizophrenia being genetic?

  Gottesman
• What is the genetic explanation of schizophrenia?


  Considerable evidence that schizophrenia runs in families and is in part genetic.
• What are the two main biological explanations of schizophrenia?

  - Genetic

  - Neural correlates + dopamine hypothesis
• Evaluate cultural bias


  Research suggests cultural bias affects the reliability of the diagnosis.Copeland gave a description of a patient of ethnic minority to 134 US and 194 British psychiatrists and 69% of US and 2% of British gave diagnosis.Weakness as suggests that the reliability of diagnosis is low.Culture plays a part in diagnosis of schizophrenia.Escobar pointed out that white psychiatrists may tend to over-interpret the symptoms of black people during diagnosis.This questions the validity of the diagnosis.
• Evaluate gender bias

  Evidence to support the gender bias in diagnosis.Loring and Powell.This suggest that there is gender bias in the diagnosis of schizophrenia which calls into question its validity
• Evaluate co-morbidity

  Evidence suggesting co-morbidity is an issue.Buckly concluded that half patients with schizophrenia:50% = depression47% = substance abuse29% = PTSD23% = OCDThis is an issue as it suggests that if schizophrenia and depression are commonly suffered together maybe they should be one disorder reduces the validity.
• Evaluate symptom diagnosis


  Symptom overlap is not an issue in the diagnosis and classification of schizophrenia.Serper assessed patients with co-morbid schizophrenia and despite significant overlap between schizophrenia and cocaine abuse it was possible to make an accurate diagnosis.Suggests that symptom overlap mightn't be an important issue affecting the validity.
• How does cultural bias affect the reliability of schizophrenia diagnosis and classification?

  - Isn't agreement on the diagnosis by psychiatrists across cultures

  - Someone could display the same symptoms but receive different diagnosis because of their ethnic background
• How does cultural bias affect the validity of Schizophrenia diagnosis?

  - Psychiatrists may impose their own cultural standards for schizophrenia onto those from other cultures = imposed etic

  - Psychiatrists are also biased towards what is "normal" in their culture = ethnocentrism
• Why do people believe their is cultural differences in the diagnoses of schizophrenia?

  -Significant variations between cultures when it comes to diagnosing schizophrenia

  - African Americans and English people from Afro-Caribbean origin are seven times more likely to be diagnosed with schizophrenia despite the rate of schizophrenia diagnosis not being high in Africa and West indies.

  THIS IMPLIES RESULT OF CULTURAL BIAS
• What does cultural differences/bias effect?

  Both validity and reliability
• Loring and Powell's research?

  Randomly selected 290 male and female psychiatrists to read cases and they either said male/ no information about gender or female on the cases.

  56% of males were diagnosed with schizophrenia whereas only 20% of females were. Gender bias didn't occur when females diagnosed the problem.
• Longenecker research?


  Reviewed studies of prevalence of schizophrenia and concluded that since 1980s men have been diagnosed with schizophrenia more often then women. Prior there had been no difference.
• What two pieces of research show the gender bias in the diagnosis of schizophrenia?

  - Longenecker

  - Loring and powell