Schizophrenia

• Schizophrenia - a serious mental illness characterised by incoherent or illogical thoughts, bizarre behaviours and speech & delusions or hallucinations
• Hallucination definition


  Unusual, sensory experiences
• Delusions (also known as paranoia) definition

  Irrational beliefs
• Reliability of diagnosis - Can a patient gain a consistent diagnosis of schizophrenia from doctor to doctor?
• Validity of diagnosis - Does a patient’s diagnosis accurately reflect the symptoms the patient is shown?
• Co-morbidity


  Two or more conditions co-exist in the same individual at the same time/ have a tendency to co-exist alongside each other.
• Schizophrenia statistics

  • Around 1% of the world population experiences schizophrenia
  • It is more common in men than women
  • It is more commonly diagnosed in cities than countryside locations
  • It is more common in the working-class than middle class people
  • The symptoms can be severe and interfere with everyday tasks - some may end up homeless or hospitalised
• Schizophrenia is a cluster of symptoms, not just one condition
• What are the two psychology manuals that recognise Schizophrenia?

  • ICD-10: International Classification of Disease edition 10 by the WHO
  • DSM-5: Diagnostic and Statistical Manual by the American Psychiatric Association
• Difference between the two classification systems diagnosis?

  The DSM-5 suggests one positive symptom needs to be present for diagnosis but ICD-10 suggests two or more negative symptoms are needed
• Types of schizophrenia

  • Paranoid schizophrenia - powerful delusions and hallucinations but few other symptoms
  • Hebephrenic schizophrenia - mainly negative symptoms
  • Catatonic schizophrenia - disturbance to movement, the individual is immobile or overactive

  The three types are recognised in the ICD-10 but have been dropped in the DSM-5
• Positive symptoms - these are additional experiences beyond ordinary life

  • Hallucinations, they could be related to environment or not I.e. hearing voices or seeing people and animals that aren’t there
  • Delusions, could be historical, political or as a religious figure. Also includes being persecuted. Individuals may also believe that they are under the control of external figures. Delusions can make individuals act in a way that makes sense to them but bizarre to others. Some delusions can lead to aggression, although individuals with schizophrenia are more victim than perpetrators of violence.
• Negative symptoms - these are a loss of usual abilities and experiences

  • Avolition (apathy) - Individuals having difficulty keeping up with goal-directed activity. Characterised by reduced motivation to carry out a range of activities. Andreason (1982) identified 3 signs of avolition: poor hygiene/grooming, lack of persistence in work/education and a lack of energy
• Other negative symptom

  • Speech poverty - changes in speech recognised by ICD-10. The individual has a reduction in the amount and quality of speech. There could be delays in the sufferer‘s verbal responses during conversations. The DSM focuses on speech disorganisation, where speech becomes incoherent/changing topic mid-sentence and classifies this as a positive symptom.
• Issues effecting the reliability and validty of diagnosing schizophrenia

  1. Inter-rater reliability is low (i.e. often psychiatrists disagree)
  2. Cultural variations in diagnosis due to different norms
  3. Symptoms of schizophrenia overlap with other disorders
  4. There is gender bias on behalf of both patient and psychiatrist
  5. Comorbidity (where sch. occurs alongside another condition)