Schizophrenia

1. Schizophrenia www.psychlotron.org.uk • Schizophrenia is not a multiple personality • A psychotic disorder involving a break with reality • Many different manifestations with a few shared features

2. Schizophrenia diagnosis • Positive Symptoms: • Hallucinations e.g. hearing voices, feeling bugs under skin • Experiences of being controlled • Disordered thinking – inability to think straight • Negative symptoms: • Flat or blunted affect (i.e. lack of emotional expression), apathy, and social withdrawal. Alogia (apparent inability or unwillingness to speak), or avolition (apparent inability or unwillingness to direct own activities) • Social & occupational dysfunction • Duration of several months

3. Schizophrenia prevalence www.psychlotron.org.uk • 1% lifetime risk in general population • Holds true for most geographical areas although rates do vary • Abnormally high in Southern Ireland, Croatia; significantly lower rates in Italy, Spain (Torrey, 2002) • Risk factors include low SES, minority ethnicity, urban residence

4. Schizophrenia onset www.psychlotron.org.uk Source: CIHI (2001)

5. Schizophrenia prognosis • ‘Rule of the thirds’ (rule of thumb): • 1/3 recover more or less completely • 1/3 episodic impairment • 1/3 chronic decline • Confirmed in US & UK (Stevens, 1978) • With treatment about 60% of patients manage a relatively normal life

6. Schizophrenia explanations • Biological • Genetics • Neurochemicals & hormones • Structural brain abnormalities • Psychological • Family dynamics • Life stress • Urbanicity

7. Schizophrenia: genetics • Prevalence of schizophrenia is the same all over the world (about 1%) • Supports a biological view as prevalence does not vary with environment • However, there are variations within broad geographical areas (e.g. Torrey 2002 – Croatia & Ireland) • Urbanicity data

8. Schizophrenia: genetics www.psychlotron.org.uk Source: Gottesman (1991)

9. Schizophrenia: genetics www.psychlotron.org.uk • Adoption studies

10. Schizophrenia: genetics • Substantial evidence for a genetic contribution • Some evidence disputed: • Shared environment issues • All the evidence also suggests environmental triggers

11. Schizophrenia & dopamine • The dopamine hypothesis: • Schizophrenia is caused by excessive DA activity. • This causes abnormal functioning of DA-dependent brain systems, resulting in schizophrenic symptoms • DA can increase or decrease brain activity depending on the system you’re looking at psychlotron.org.uk

12. The dopamine hypothesis • Wise & Stein (1973) report abnormally low levels of DBH in post-mortem studies of S patients • Would suggest abnormally high DA activity as DBH needed to break DA down • Can’t rule out cause of death or post-mortem changes as a source or error

13. The dopamine hypothesis • Overdose of amphetamine (DA agonist – agonist = a substance that initiates a response when combined with a receptor) can produce S-like symptoms. S patients have abnormally large responses to low amphetamine doses • Suggests a role for DA in S symptoms • Suggests that the issue is over-sensitivity to DA rather than excessive DA levels

14. The dopamine hypothesis • S symptoms can be treated with DA antagonists (substances that intefere with the physiological action of others) (e.g. chlorpromazine). These are effective in 60% of cases with more impact on positive symptoms. • Supports role of DA again, but what about 40% who don’t respond? • Lack of impact on negative symptoms hints at two separate syndromes

15. Biology and Schizophrenia • Consistent evidence for abnormal brain functioning in S patients but no single factor identified. • Two syndromes? One caused by DA activity & associated with +ve symptoms; other caused by brain degeneration (e.g. enlarged brain ventricles) & associated with –ve symptoms. • Cause & effect issues everywhere

16. Behaviourist • Schizophrenia is the result of faulty learning in childhood. • E.g. parental disinterest leads to child focusing on inappropriate environmental cues as opposed to normal social ones. • Some evidence to support in social skills training.

17. Humanistic - Family Systems Theory • Origins in: • The psychoanalytical tradition (the influence of the family on abnormal behaviour) • Systems thinking (idea that things are best understood by looking at the relationships between a set of entities)

18. F M C1 C3 C2 Family System A family can be seen as a set of entities, each interacting with all the others. The behaviour of each entity can only be understood by looking at its relationships with the others psychlotron.org.uk

19. F M C1 C3 C2 Family System If one person starts to behave abnormally the problem might not lie within that person Their behaviour may be a manifestation of a problem occurring within the wider family system C2 psychlotron.org.uk

20. Double Bind Theory (Bateson, 1956) • Schizophrenia is a consequence of abnormal patterns in family communication • The patient is a ‘symptom’ of a family-wide problem • They become ‘ill’ to protect the stability of the family system psychlotron.org.uk

21. Double Bind Theory • In a double bind situation a person is given mutually contradictory signals by another person • This places them in an impossible situation, causing internal conflict • Schizophrenic symptoms represent an attempt to escape from the double bind psychlotron.org.uk

22. Double Bind Theory • Bateson (1956) reports clinical evidence (interviews, observations) illustrating use of double bind communication by parents of schizophrenia patients • Issues of researcher (confirmatory) bias • Problems with direction of causality psychlotron.org.uk

23. Double Bind Theory • Liem et al (1974) compared communication patterns in families with & without a schizophrenic member • Abnormality in parental communication was a response to the schizophrenic symptoms, not vice versa psychlotron.org.uk

24. Double Bind Theory • Some evidence that family processes play a role in relapse of schizophrenia patients following stabilisation • Relapse more likely (58% vs. 10%) where family is high in ‘expressed emotion’ (Brown et al, 1966) • Families high in criticism, hostility & over-involvement lead to more relapse (Vaughn & Leff, 1976)