Cognitive explanations

• Cognitive explanations focus on the role of mental processes
• Schizophrenia is associated with several types of abnormal information processing which can explain schizophrenia as a whole
• Schizophrenia is characterised by disrupted thought processing: reduced processing in the ventral striatum is associated with negative symptoms
• Christopher Frith et al (1992)

  • Identified 2 kinds of dysfunctional thought processing: metarepresentation and central control
• Metarepresentation refers to the cognitive ability to reflect on thoughts and behaviours
• Dysfunctional metarepresentation disrupts our ability to recognise our thoughts and behaviours as being carried out by ourselves and not someone else
• Metarepresentation would explain hallucinations of voices and delusions like thought insertion
• Faults in cognitive ability result in delusions of control- believing you are being controlled by aliens
• Central control refers to the ability to suppress automatic responses while performing deliberate actions instead
• Disorganised speech and thought disorders could result from the inability to suppress automatic thoughts and speech triggered by other thoughts- the lack of central control
• Schizophrenics tend to have derailed thoughts and speech as each thought triggered associations and the patient cannot suppress automatic responses to these
• The Stroop test is a cognitive test used to assess the ability to inhibit cognitive interference
• In the Stroop test, our natural reaction is to read the word, but the objective is to say the colour of the word instead
• Stirling et al (2006)

  • Studied the performance of people with schizophrenia and non-patient groups on the Stroop test
  • Schizophrenics got a mean of 123 seconds compared to the control group's 58 seconds
  • Shows a lack of central control
• STRENGTHS

  • Strong evidence: Stirling et al's Stroop test
  • Cognitive therapies: More affective in reducing symptom severity than antipsychotics
• WEAKNESSES

  • Correlation: Cannot explain distal causes, cannot prevent schizophrenia, only treat it
  • Alternative explanations: biological. Diathesis-stress model