OCD

1. Psychopathology

2. O.C.D.
The specification:
• The biological approach to explaining and
treating O.C.D: genetic and neural
explanations; drug therapy.

3. Biological explanations: O.C.D
• You need to know the behavioural,
emotional and cognitive characteristics of
OCD.
• You need to be able to outline these
characteristics.
• You need to be able to identify them in a
description of someone’s behaviour.

4. O.C.D

5. O.C.D.

6. O.C.D.

7. Biological explanations: O.C.D
• The basic assumptions of the biological
approach are:
• Genes.
• Neural structures.
• Neurochemistry.

8. Biological explanations: O.C.D
• The application of the biological approach to
mental disorders is known as the medical
model.
• Mental disorders are just like physical illnesses.
• Abnormal biological processes cause abnormal
psychological processes.

9. Biological treatments: O.C.D
• A physical illness requires a physical
treatment.
• Drugs.

10. Biological explanations: Genes
• O.C.D is caused by:
• Genes
• Some people inherit genes that make
them vulnerable to the development of
O.C.D.

11. Biological explanations: Genes
• Twin studies.
• Twin studies have found:
• O.C.D. has a genetic basis.

12. Biological explanation: genes

13. Biological explanation: genes

14. Biological explanations: Genes
• Twin studies use a statistical technique to
calculate a concordance rate.
• One identical twin has O.C.D. the other
identical twin has O.C.D.
• The concordance rate from twin study research
varies significantly but suggests that inherited
genes are a significant cause of O.C.D.

15. Biological explanations: Genes
• This research has attempted to identify the
specific genes that cause O.C.D.
• This research has been inconclusive.
• O.C.D has a ‘polygenic’ basis.

16. Genes: evaluation
• No twin study has found a 100%
concordance rate.
• Genes can’t be the only cause of O.C.D.

17. Genes: evaluation
• The diathesis-stress model.
• Some people inherit genes that make
them vulnerable to developing O.C.D.

19. Genes: evaluation

20. Genes: evaluation
• This genetic vulnerability interacts with that
person’s environment.
• Physical environment.
• Social environment.
• Trauma.

21. Genes: evaluation
• The environment can activate or trigger
inherited genes.
• The vulnerable person develops O.C.D.
• Genome = genes inherited.
• Phenotype = the environment.

22. Biological explanations: Genes
Read p.37 - 38 of the psychopathology
booklet: Genetic Explanations and complete
the genetic explanation table.

23. Key words
• Serotonin: neurotransmitter that regulates mood.
May cause some of the symptoms of O.C.D.
• Dopamine: neurotransmitter that plays an important
role in regulating motivation and reward. May cause
some of the symptoms of O.C.D.
• Polygenic: more than one gene.
• Concordance rate: the match expressed in % that one
twin diagnosed with O.C.D. is diagnosed with O.C.D.

24. Neural explanations
• Abnormal brain structures.
• Abnormal brain function.
• Abnormal brain structures cause abnormal
brain function.

28. Neural explanations: abnormal brain
function
• Serotonin is a neurotransmitter.
• It regulates mood.
• When levels are normal you feel:
• Happier
• Calmer
• More focussed
• Less anxious

29. Neural explanations: abnormal brain
function
• When levels of serotonin are abnormal
you feel:
• Anxious
• Unfocussed
• Can’t concentrate
• Not in control of your thoughts

30. Neural explanations: abnormal brain
function
• Abnormally low levels of serotonin are
linked to the symptoms of O.C.D.
• One cause of O.C.D. may be the abnormal
production and processing of serotonin.

31. Neural explanations: abnormal brain
structures

33. Parahippocampul gyrus

34. Abnormal brain function: evaluation
• Research has identified two abnormalities in the
human serotonin transporter gene in DNA
samples of people with O.C.D.
• These abnormal genes cause low levels of
serotonin in the brain.

35. Abnormal brain function: evaluation
• Drugs that raise levels of serotonin in
the brain reduce the symptoms of O.C.D.
• Anti-depressants.
• SSRI’s
• Selective serotonin reuptake inhibitors.

36. Abnormal brain structures: evaluation
• Research has not identified specific brain
structures or specific brain systems that are
responsible for O.C.D.
• Brain abnormalities may be caused by
O.C.D.
• The brain abnormality may not cause
O.C.D.

37. Biological treatment: drugs
• The main biological treatment for O.C.D. is drug
therapy.
• Drugs that raise levels of serotonin in the brain
are prescribed.
• Anti-depressants are prescribed.

38. SSRI’s

39. Biological treatment: drugs
• SSRI’s.
• Selective Serotonin Reuptake Inhibitors.
• SSRi’s block the reabsorption of serotonin back
into the brain cell that has released it.
• Over time levels of serotonin rise in the brain.

41. Biological treatment: drugs
• Other types of anti-depressants may be
prescribed:
• SNRI’s
• Tricyclic’s

44. Biological treatment: drugs
• Other types of drugs may be prescribed:
• Anti-anxiety drugs.
• Benzodiazapines.

46. Drugs: evaluation
• Drugs work.
• They reduce the symptoms of
O.C.D.
• A meta-analysis (2009) found
that SSRI’s were effective in
reducing the symptoms of
O.C.D.

47. Drugs: evalaution
Drugs are cheap.

48. Biological treatment: drugs
Drugs have side
effects.

49. Biological treatment: drugs
• Negative results are
not published.
• Researchers only
send reports of
research that find
positive results to
academic journals.