The behavioural approach to explaining OCD

Question 1

Which psychological approach is used to explain OCD?

Answer 1

The biological approach is used to explain obsessive compulsive disorder.

Question 2

The biological approach is used to explain OCD. What is the biological approach?

Answer 2

The biological approach is a perspective that emphasises the important of physical processes in the body such as genetic inheritance and neural function.

Question 3

How many biological explanations of OCD have been proposed?

Answer 3

Two biological explanations of OCD have been proposed.

Question 4

Which two biological explanations of OCD have been proposed?

Answer 4

• Genetic

- Neural explanation

Question 5

What are genetic explanations of OCD?

Answer 5

Genes make up chromosomes and consist of DNA which codes the physical features of an organism and psychological features. Genes are transmitted from parents to offspring.

Question 6

Which psychologist provided support for the genetic explanation of OCD?

Answer 6

Lewis (1936)

Question 7

How did Lewis provide support for the genetic explanation of OCD?

Answer 7

Lewis observed that of his OCD patients 37% had parents with OCD and 21% had siblings with OCD. This suggests that OCD runs in families.

Question 8

From his observational study, Lewis concluded that OCD runs in families. What specifically is passed on from one generation to another?

Answer 8

It has been argued that genetic vulnerability is passed on from one generation to the next, not the certainty of OCD.

Question 9

It has been argued that genetic vulnerability is passed on from one generation to the next, not the certainty of OCD. How can this be linked to the diathesis-stress model?

Answer 9

According to the diathesis-stress model certain genes leave some people more likely to suffer a mental disorder bit it is not certain. Some environmental stress is necessary to trigger the condition.

Question 10

OCD is a polygenetic disorder. What does this mean?

Answer 10

This means that OCD is not caused by one single genes but that several genes are involved.

Question 11

OCD is a polygenetic disorder. How many genes are thought to be involved in this psychological disorder?

Answer 11

Taylor (2013) has analysed findings of previous studies and found evidence that up to 230 different genes may be involved in OCD.

Question 12

Up to 230 genes are thought to be involved in OCD. What are these genes specifically called?

Answer 12

Candidate genes

Question 13

Why can OCD be described as ‘etiologically heterogeneous’?

Answer 13

OCD can be described as etiologically heterogeneous because not all individuals with OCD will carry the same gene.

Question 14

Which two candidate genes are students required to know for the exam?

Answer 14

• COMT

- SERT (5HTT)

Question 15

How does the COMT gene regulate internal functions?

Answer 15

COMT regulates dopamine and is more common in those with OCD. Dopamine regulates control impulses and emotional responses. When there is too much of this chemical it can cause people to act impulsively.

Question 16

How can the action of COMT be used to explain behavioural characteristics of OCD?

Answer 16

When there is too much dopamine in the brain, people may act impulsively (e.g. locking doors repeatedly).

Question 17

Why might there be too much dopamine in the brain?

Answer 17

The vesicles are full of neurotransmitters so more are related into the synaptic cleft. These neurotransmitters either bind to receptor molecules on the post-synaptic neurone or diffuse back into the pre-synaptic neurone. More neurotransmitters will be fired regularly.

Question 18

How does the SERT gene regulate internal functions?

Answer 18

SERT regulates the efficiency of serotonin across a synapse. If a person has low levels of serotonin, normal transmission across the synapse does not take place. This regulation is less in a person with OCD compared to the normal functioning person.

Question 19

How can the action of SERT be used to explain emotional characteristics of OCD?

Answer 19

Lower regulation of serotonin is associated with emotional characteristics of OCD as it is likely to cause low moods. This is because there are fewer neurotransmitters in the vesicles and so fewer will be fired when they reach the post-synaptic neurone. This results in lower levels of serotonin in the body.

Question 20

What are neural explanations of OCD?

Answer 20

Neural explanations view that physical and psychological characteristics are determined by the behaviour of the nervous system, in particular the brain.

Question 21

Neural explanations of OCD are particularly concerned with how areas of the brain influence the development of a psychological disorder. Which two parts of the brain are students required to know?

Answer 21

• The left parahippocampal gyrus

- The frontal lobe

Question 22

How is the left parahippocampal gyrus associated with OCD?

Answer 22

The left parahippocampal gyrus is associated with processing unpleasant information emotions. This usually functions abnormally in OCD and can therefore influence emotional characteristics.

Question 23

How is the frontal lobe associated with OCD?

Answer 23

OCD is the part of the brain responsible for decision making and logical thinking. If this is damaged, a person may not be able to think logically and will be unable to make appropriate decisions.