Schizophrenia

• What is schizophrenia defined as?

  A mental health disorder marked by severely impaired thinking, emotions, and behaviours. It is experienced by around 1% of the population
• What types of symptoms do sufferers of schizophrenia experience?

  They may experience either positive or negative symptoms.
• What are positive symptoms of schizophrenia?

  Symptoms that are additional experiences beyond those of ordinary existence, such as hallucinations and delusions. Focused on in the DSM.
• What are negative symptoms of schizophrenia?

  Symptoms that involve the loss of usual abilities and experiences, such as speech poverty and avolition. Focused on in the ICD.
• What are hallucinations in the context of schizophrenia?

  A positive symptom characterised by a distorted view of real stimuli or perceptions of stimuli with no basis in reality.
• What causes auditory hallucinations in schizophrenia?

  They are thought to be caused by an excess of dopamine receptors in Broca’s area.
• What are delusions in schizophrenia?

  A set of beliefs with no basis in reality, such as paranoia about being stalked.
• What is speech poverty in schizophrenia?

  An abnormally low level of the frequency and quality of speech.
• What is avolition in schizophrenia?

  A subjective reduction in interests, desires, and goals, leading to a lack of motivation to carry out a range of activities.
• What are the two classification systems for mental disorders?

  The DSM-5 and the ICD-10.
• How do the DSM-5 and ICD-10 differ in diagnosing schizophrenia?

  The DSM-5 requires at least 2 symptoms, while the ICD-10 has a broader approach.
• What is the significance of the differences between the DSM and ICD?

  They differ in the organisations that produce them, the number of symptoms, the specificity of symptoms required for diagnosis and whether subtypes are recognised. Subtypes are currently recognised in the ICD-10 only (used to be recognised in the DSM).
• What is co-morbidity in the context of schizophrenia?

  The high frequency of diagnosis of two disorders together, such as schizophrenia and depression.
• A weakness of classification/diagnosis of schizophrenia?

  Schiz may not exist as a single condition; it is often co-morbid with depression, PTSD or substance abuse. Buckley et al (2009) found that 29% of their SZ patients suffered from PTSD, while 50% suffered from depression. This means we are unable to establish a cause and effect relationship.
• A weakness of classification/diagnosis of schizophrenia?

  The validity of diagnosis can be questioned because schiz is hard to distinguish from other disorders with similar symptoms, such as bipolar disorder which also has both positive and negative symptoms. This can lead to unreliable or incorrect diagnosis.
• A weakness in the classification/diagnosis of schizophrenia?

  There may be gender bias (beta bias). Men are more commonly diagnosed than women especially after the 1980s. This could be because dispositional traits of most women, such as high interpersonal functioning and being able to work even when suffering, means that such traits may mask the symptoms of schizophrenia or distort their severity so that they are not serious enough to call for a diagnosis. This means women are not receiving the clinical treatment and services they deserve.
• A strength of the classification/diagnosis of schizophrenia?

  The DSM-5 has high reliability. It has increased both test-retest and inter-rater reliability of schizophrenia diagnosis by providing a consistent framework. Osorio et al (2019) reported excellent reliability in the diagnosis of 180 people using the DSM-5. There was a correlation coefficient of +0.92 and +0.97 respectively. This means the results are more accurate.
• A weakness of classification/diagnosis of schizophrenia?

  There may be culture bias. Some symptoms of schizophrenia have different meanings in different cultures. For example, hearing voices may is considered a desirable sign of increased spirituality and connectedness with ancestors in some Afro-Caribbean cultures. This leads to individuals from these cultures living in the UK are 10 times more likely to be diagnosed than white British people as both classification systems would view this as a symptom of schizophrenia. This can reduce the validity of the diagnosis.
• What evidence suggests a genetic basis for schizophrenia?

  Gottesman (1991) demonstrated a positive correlation between genetic similarity and risk of developing schizophrenia. He carried out a large-scale family study to investigate the genetic links between families where schizophrenia is present in one or more family members.
• What are the concordance rates for schizophrenia in different family members?

  48% for monozygotic twins, 17% for dizygotic twins, 9% for siblings, and 6% for parents.
• What do candidate genes represent in schizophrenia?

  Genetic variations that marginally increase the risk of developing schizophrenia.
• What does the original dopamine hypothesis suggest?

  Hyperdopaminergia in the subcortex is responsible for schizophrenia.
• What does the revised dopamine hypothesis suggest?

  Hypodopaminergia in the cortex is more likely responsible for schizophrenia.
• How do both hyper- and hypodopaminergia contribute to schizophrenia?

  Both contribute in different areas of the brain to the development of schizophrenia.
• What role does Broca’s area play in schizophrenia?

  It may have an excess of D2 receptors responsible for auditory hallucinations.
• What did Goldman Rakic et al (2004) suggest about hypodopaminergia?

  It may be responsible for negative symptoms like speech poverty and avolition.
• What are neural correlates?

  Specific patterns of cortical activity or neural structures associated with psychological symptoms.
• What did Juckel et al (2006) find regarding the ventral striatum?

  Low activation levels may be associated with the negative symptom of avolition.
• What did Allen et al (2007) conclude about auditory verbal hallucinations?

  They are associated with functional abnormalities in the anterior cingulate and left temporal cortex.
• What did Brown et al (2002) find regarding paternal age and schizophrenia risk?

  The risk of having offspring with schizophrenia increases if the father is over 50 years old.
• What is the evidence for the dopamine hypothesis described as?

  Mixed, with some supporting and some criticizing the emphasis on dopamine's role.
• What did Tauscher et al (2014) find regarding antipsychotics?

  They alleviate symptoms of schizophrenia by acting as dopamine antagonists.
• What criticism do Moghaddam and Javitt (2012) have regarding the dopamine hypothesis?

  They argue that it emphasizes the role of dopamine too much.
• What is the role of dopamine in schizophrenia according to the dopamine hypothesis?

  Dopamine has a key role in the development of schizophrenia.
• What do Moghaddam and Javitt (2012) criticize about the dopamine hypothesis?

  They criticize it for emphasizing the role of dopamine too much.
• What neurotransmitters does the antipsychotic Clozapine act upon?

  Clozapine acts upon glutamate and serotonin.
• What is a major issue with using neural correlates to explain schizophrenia?

  Correlational evidence does not account for the 'third variable problem'.
• What does the term 'schizophrenogenic mother' refer to?

  It refers to a mother characterized as cold and rejecting.
• What are the psychological explanations for the development of schizophrenia?

  • Abnormal family communication styles
  • Schizophrenogenic mother
  • Double-bind theory
  • High levels of expressed emotion
• How does double-bind theory explain the development of schizophrenia?

  It suggests children receive mixed messages from parents, leading to confusion.