Cognitive explanations

• Cognitive explanations of schizophrenia


  Focus on dysfunctional thought processing
• Dysfunctional thought processing


  Errors and biases relating to the interpretation of internal and external information can give rise to symptoms that characterise schizophrenia
• Dysfunctional Thought Processing Due to a Lack of Meta-cognition


  • Meta-cognition is the cognitive ability for an individual to recognise their own sensations, thoughts and behaviour
  • It enables an individual to understand that these are different to external stimuli and the thoughts and behaviours of others
  • If an individual lacks this ability, they may not be able to distinguish between internal experiences and external stimuli, which can lead to psychosis
  • For example, an individual generates a thought using their own inner voice, but they don't realise this is an internal experience, and instead falsely interpret this as the voice of another person despite not hearing the voice as an external stimulus
  • This is therefore an auditory hallucination ('hearing voices') and means the person does not have an accurate perception of reality
• Dysfunctional Thought Processing Due to a Lack of Central Control

  • Central control is the cognitive ability for an individual to suppress automatic responses while we perform deliberate actions instead
  • The inability of a schizophrenic to suppress automatic thoughts and speech triggered by external stimuli as well as their own internal thoughts may lead to symptoms of disorganised speech and thought disorder
  • This can involve an individual experiencing derailment (loss of concentration whilst thinking, speaking or listening) because a particular word heard, seen or thought triggers automatic associations to other words and thoughts that cannot be suppressed
• Meta-cognition

  The ability to self-monitor and distinguish internal and external signals
• Research on lack of meta-cognition in schizophrenia

  • Participants required to draw circles on a writing pad connected to a PC monitor and continually observe the relationship between their hand movements and the visual consequences
  • Schizophrenic participants significantly more impaired in their ability to detect a mismatch between self-generated movement and consequences on the screen
• Lack of meta-cognition in schizophrenia

  Supports the idea that schizophrenics lack the cognitive ability to self-monitor and distinguish internal and external signals
• Knoblich et al. (2004): 'Provided research supporting a lack of meta-cognition in schizophrenia'
• Stroop Test


  • Participants identify the colour of ink that words are written in whilst suppressing the impulse to say the word itself
• 30 patients with symptoms of schizophrenia took on average twice as long to read out the colours than 18 non-patient controls
• Schizophrenia is linked to

  A lack of the cognitive ability of central control
• The lack of central control meant the patients struggled to suppress the automatic impulse to say the words themselves
• Establishing causality between dysfunctional thought processing and schizophrenia


  A limitation of cognitive explanations of schizophrenia
• It is difficult to ascertain whether cognitive factors are a cause or a consequence of schizophrenic symptoms, despite there being an apparent relationship
• Hallucinations


  Caused by the dysfunctional thought processing of auditory information due to a lack of meta-cognition
• Dysfunctional thought processing

  Possible consequence of schizophrenia after changes in a person's biology have occurred
• It is difficult to establish whether the cause of schizophrenia is cognitive because sufferers are only investigated after they have been diagnosed
• Solution to establish causality

  1. Conduct 'at-risk' studies of children with schizophrenic parents involving longitudinal, prospective research

  2. As a child grows up, it may be possible to establish whether dysfunctional thinking does indeed arise before the onset of schizophrenic symptoms; or whether this is instead a consequence
• Cognitive explanations alone do not provide a full explanation of schizophrenia
• Cognitive explanations


  Can adequately explain what dysfunctional thought processes that an individual is currently experiencing
• Cognitive explanations can fail to explain why they have dysfunctional thinking
• Contributing factors that better explain why schizophrenic symptoms develop

  • Biological (such as inheriting a faulty COMT gene)
  • Social (such as being a victim of family dysfunction)
• Cognitive explanations are compatible with other explanations such as biological and social factors
• Cognitive neuropsychological explanations

  Combine cognitive and biological aspects to provide a holistic account of the disorder
• Schizophrenics may have a cognitive impairment


  Makes it difficult for them to distinguish internal and external auditory experiences
• Increased dopamine activity in Broca's area (responsible for speech production)


  Can lead to auditory hallucinations and speech difficulties
• Holistic accounts integrate both distal causes (i.e. origins) of schizophrenia and proximal causes (i.e. current symptoms) which together create a more complete understanding of the disorder