Psychopathology L12

Question 1

Biological approach definition

Answer 1

• It assumes that OCD is caused by genetic & biochemical factors (neurotransmitters/hormones)

Question 2

Genetic explanations of OCD

Answer 2

• Some researchers suggest that OCD is an inherited condition & therefore a vulnerability to developing the condition is passed on across generations
• OCD is polygenic: one single gene is not responsible for causing OCD
• Instead, as many as 230 genes may be responsible for causing OCD (these are known as candidate genes)
• Aetiological heterogeneity suggests that different combinations of genes may cause OCD in different people

Question 3

How does the COMT gene play a role in causing OCD? (Genetic explanation)

Answer 3

• It regulates the production of a neurotransmitter called dopamine
• One variation of the COMT gene results in higher levels of dopamine
• This is more common in OCD patients compared to those who do not have OCD

Question 4

How does the SERT gene play a role in causing OCD? (Genetic explanation)

Answer 4

• It affects the transportation of serotonin, causing lower levels of serotonin
• Low levels of serotonin lead t obsessional thoughts & therefore have been linked to OCD

Question 5

2 strengths of genetic explanations of OCD

Answer 5

1. It has research support
   - Nestadt Et al (2010) found that the concordance rates for OCD between monozygotic twins (identical twins - 68%) was much higher than between dizygotic twins (non-identical twins - 32%)
   - However, the concordance rates are not 100%, so it cannot be completely genetic
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2. Animal studies have found that there is a genetic basis for repetitive ritualistic behaviour in animals
   - Ahmari (2016) found a common gene in mice who display ritualistic behaviour

Question 6

1 weakness of genetic explanations of OCD

Answer 6

• Around half of all cases of OCD tend to follow trauma, undermining the genetical explanation of OCD
• It also cannot account for cases of OCD in families where there is no previous history of OCD

Question 7

Neural explanations of OCD definition

Answer 7

• Dopamine & serotonin are neurotransmitters that affect mood
• Abnormal levels of these neurotransmitters are associated with abnormal transmission of mood-related information

Question 8

What do high levels of dopamine cause? (Neural explanation of OCD)

Answer 8

• OCD sufferers have high levels of dopamine
• This has been linked to over hyperactivity in the basal ganglia area of the brain
• This causes repetitive motor functions (e.g: compulsions)

Question 9

What do low levels of serotonin cause? (Neural explanation of OCD)

Answer 9

• Serotonin plays a key role in operating the caudate nucleus in the basal ganglia of the brain
• Low levels of serotonin cause the caudate nucleus to malfunction & results in obsessions

Question 10

1 advantage of neural explanations of OCD

Answer 10

• Antidepressant drugs increase serotonin levels in OCD patients, leading to a reduction in OCD symptoms
• Therefore it has good evidence to suggest that low levels of serotonin could be a cause for OCD

Question 11

1 disadvantage of neural explanations for OCD

Answer 11

• *Neurotransmitters**, such as dopamine & serotonin may not necessarily cause OCD
• Instead, low levels of serotonin and high levels of dopamine might be a symptom of OCD