Cognitive explanations of schizophrenia

Dysfunctional thought processing

Dysfunctional thought processing = cognitive habits or beliefs that cause the individual to evaluate information inappropriately and produces undesirable consequences

Frith et al. (1992) identified two kinds of dysfunctional thought processing that could underlie some symptoms of schizophrenia:

Metarepresentation – this is the cognitive ability to reflect on thoughts and behaviour which allows us insight into our own intentions and goals. Dysfunction in this would disrupt our ability to recognise our own actions and thoughts as being carried out by ourselves rather than someone else. This explains auditory hallucinations and delusions like thought insertion.

Central control – this is the cognitive ability to suppress automatic responses while we perform deliberate actions instead.

 Dysfunction in this would lead to disorganised speech and thought disorder as we are unable to suppress automatic thoughts and speech triggered by other thoughts. For example, schizophrenics tend to experience derailment of thoughts and spoken sentences because each word triggers associations, and the patient can’t suppress automatic responses to them.

Cog explanation eval

Sarin and Wallin 2014

Positive evidence for positive symptoms of SZ rooted in faulty cognition like lack of reality testing, impaired self-monitoring and experiencing  ther own thoughts as voices. Useful for therapists/ treatments

NICE 2014

Effectiveness of CBTp.. review by NICE found consistent evidence CBTp reduced symptom severity and improved levels of social functioning.

Integrated models of SZ

Cognitive model of SZ explains certain aspects well (cognitive impairment) but not others (social adversity)

Howes and Murray 2014