Psychopathology: Biological Approach to explaining OCD

Question 1

What are the explanations under biological approach?

Answer 1

• Genetic Explanations
• Neural Explanations
• Neuroanatomy

Question 2

What is the genetic explanations?

Answer 2

• OCD may be inherited.
• Evidence comes from - family, twin studies and research methods.
• Looks at genes (COMT and SERT)

Question 3

What two genes are used in genetic explanations?

Answer 3

COMT & SERT

Question 4

What is SERT gene?

Answer 4

Affects the transport of serotonin, creating lower levels of this neurotransmitter.
-Low levels of serotonin have been implicated with OCD.

Question 5

What is COMT gene?

Answer 5

Helps reduce the action of dopamine.

• Variation in COMT gene may decrease amount of COMT available and dopamine isn’t controlled.
• Too much dopamine is associated with OCD.

Question 6

What family study supports genetic explanation?

Answer 6

Billett (1998)

Question 7

What is Billett (1998)

Answer 7

• Meta-analysis of 14 twin studies.

- On average identical twins are 2x more likely to develop the disorder than non-identical.

Question 8

What are neural explanations?

Answer 8

Lower levels of serotonin found in OCD sufferers.
Dopamine levels are high in people with OCD.
Serotonin deficiency initiates faulty signals from OFC.

Question 9

What does low levels of serotonin cause in OCD? (Neural explanations)

Answer 9

• Serotonin may prevent repetition of tasks and is in too low level.
• Could be unable to inhibit the repetition of an action resulting in obsessive thoughts.

Question 10

What study supports neural explanations?

Answer 10

Pigott (1992) - Antidepressant drugs that increase serotonin activity have been seen to reduce OCD symptoms.

Question 11

What is the neuroanatomy explanations?

Answer 11

Basal Ganglia.

• Communication between this and other structures may be disrupted in OCD patients. (Often occurs in people with Parkinson’s)
• Cutting comm from basal ganglia to frontal cortex can reduce symptoms in severe cases.

Question 12

Genetic explanations Evaluation?

Answer 12

• Studies shown a reduction in dopamine levels is positively correlated with a reduction in OCD symptoms.
• Animal studies increased dopamine levels caused animals to display OCD behaviour.
• Hu (2006) supports.

Question 13

Neural causes evaluation?

Answer 13

• Improvement rates from use of drugs only at 50% so must be other causes.
• Time delay - effect on OCD may take weeks.

Question 14

Overall Evaluation?

Answer 14

• Research support + scientific research.
• Biologically determinist: suggests OCD is due to uncontrollable gene + neuronal factors.
• Biologically reductionist: ignores the role of family, or cognitive explanations.