what is schizophrenia?
a severe psychotic disorder where contact with reality and insight are impaired.
two major classification systems for disorders
The definitions in these manuals differ. This can lead to inconsistency and therefore unreliability however it can also be good since there is competition to be the “best most accurate manual”.
ICD classification of Schizophrenia
DSM classification of Schizophrenia
what are positive symptoms (give examples within schizophrenia)?
what are hallucinations?
what are delusions?
what are negative symptoms (give an example from schizophrenia)?
what is avolition (apathy)?
what is speech poverty (compare ICD and DSM)?
In the ICD-10, speech poverty is considered a negative symptom of schizophrenia characterised by:
- changes in patterns of speech
- reduction in the amount and quality of speech
- sometimes accompanied by a delay in verbal responses during conversation
The DSM 5 places emphasis more on speech disorganisation in which the speech becomes incoherent or involves mid-sentence topic changes, this is classified as a positive symptom.
what were the subtypes of Schizophrenia?
Paranoid Schizophrenia - powerful delusions but relatively few other symptoms
Hebephrenic Schizophrenia - primarily negative symptoms present (also called disorganised)
Catatonic Schizophrenia - disturbance to movement leaving the sufferer immobile
what is classification?
the process of organising symptoms into categories based on which symptoms cluster together in sufferers. Psychologists use the DSM and ICD to diagnose patients with Schizophrenia
what is diagnosis?
the assigning of a label to a patient
reliability issues in the diagnosis/classification of schizophrenia
validity issues in the diagnosis/classification of schizophrenia
Cheniauz et al. (2009) - schizophrenia diagnosis has low criterion and inter-rater reliability
> some patients may not receive a diagnosis when it is needed, inhibiting their ability to obtain treatment
low criterion validity (either over- or under- diagnosed using the ICD or DSM), may receive a diagnosis when they shouldn’t, perhaps leading to the use of unsuitable medications
Buckley et al. (2009) - comorbidity of Schizophrenia
Longenecker et al. (2010) - prevalence in men vs women
Cotton et al (2010) - characterisation in men vs women
found that female patients typically function better than men, being more likely to work and have good family relationships.
> so may go undiagnosed
Harrison et al. - culture bias
writing about issues with classification/diagnosis of schizophrenia
Rosenhan’s study: ‘On Being Sane in Insane Places’ (1973)
> testing stability of diagnosis over time (when symptoms change)
- 8 pseudopatients at different hospitals claimed to hear unfamiliar voices of the same sex as the pseudopatient saying ‘empty’, ‘hollow’, and ‘thud’
- 7 were diagnosed with schizophrenia and 1 with manic depression
- once admitted, they behaved normally and wrote down their observations of the institution
- staff never detected that they were ‘sane’ and interpreted ‘normal’ behaviours as abnormal eg. pathological writing
conclusions based on Rosenhan’s research
It is also very difficult to get a diagnosis removed, especially if it is one that invalidates your view of reality.
what are the biological explanations for schizophrenia?
genetics and neural correlates