Psychopathology - biological approach to explaining OCD

Question 1

what are genetic explanations

Answer 1

Aubrey Lewis (1936)
- 37% had parents with OCD
- 21% had siblings with OCD
- genes are involved in the vulnerability of OCD

Question 2

what are candidate genes

Answer 2

• genes that create vulnerability for OCD
• seratonin

Question 3

how is OCD polygenic

Answer 3

• caused by a combination of genes
  Steven Taylor (2013)
• up to 230 genes may be involved

Question 4

what are the different types of OCD

Answer 4

Aetiologically Heterogenous
- origins of OCD may vary from each person

Question 5

what is the support for genetic explanations

Answer 5

Nestadt et al (2010)
- reviewed twin studies
- 68% MZ twins shared OCD
- 31% DZ twins shared OCD
- some genetic influence on the development of OCD

Question 6

what are the limitations of genetic explanations

Answer 6

Cromer et al (2007)
- over half of OCD clients in her sample had experienced a traumatic event
- OCD more severe in those with one or more traumas

Question 7

what are neural explanations

Answer 7

• neurotransmitters and structures of the brain

Question 8

what is the role of serotonin

Answer 8

• neurotransmitters relay information from one neurone to another
• low serotonin levels then normal transmission of mood relevant information cannot take place and person experiences low mood
• some cases of OCD explained by a reduction in the functioning of the serotonin system

Question 9

what are decision making systems

Answer 9

• hoarding disorders associated with impaired decision making
• associated with abnormal functioning of lateral frontal lobes - responsible for logical thinking
• left Para hippocampal gyrus associated with unpleasant emotions functions abnormally in OCD

Question 10

what are the strengths of neural explanations

Answer 10

• AD can reduce OCD symptoms suggesting serotonin is involved in OCD
• OCD symptoms are biological in origin - symptoms of Parkinson’s
• biological disorder produces OCD symptoms then biological processes underline OCD

Question 11

what are the limitations of neural explanations

Answer 11

• co-morbidity
• people with OCD can also have clinical depression
• depression causes disruption to serotonin
• serotonin activity is disrupted in many people with OCD because they are also depressed
• serotonin may not be relevant to OCD