The biological approach to explaining OCD

Question 1

what does the diathesis-stress model state?

Answer 1

certain genes mean some people are more likely to suffer a mental disorder but it is not certain -some environmental stress is necessary to trigger the condition

Question 2

define candidate genes

Answer 2

researchers have identified candidate genes, which create vulnerability for OCD. Some of these genes are involved in regulating the development of the serotonin system.

Question 3

OCD is polygenic what does this mean?

Answer 3

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

Question 4

who analysed findings of previous studies and found evidence that up to 230 different genes may be involved in OCD

Answer 4

Taylor

Question 5

Genes that have been studied in relation to OCD include those associated with the action of which neurotransmitters?

Answer 5

dopamine + serotonin

Question 6

what does aetiologically heterogeneous mean?

Answer 6

that the origin of OCD has diff causes

eg one group of genes may cause OCD in one person but another group of genes may cause OCD in another person

Question 7

there is also some evidence to suggest that different types of OCD may be the result of ?

Answer 7

particular genetic variations

Question 8

define neural explanations

Answer 8

the genes associated with OCD concerns the role of the neurotransmitter serotonin, which is believed to help regulate mood.

Question 9

explain the role of serotonin in explaining ocd

Answer 9

One explanation of OCD concerns the neurotransmitter serotonin which regulates mood. Neurotransmitters are responsible for relaying information from one neuron to another. If a person has low levels of serotonin then normal transmission of mood-relevant info doesn’t take place and mood is affected. Some cases of OCD can be explained by a reduction in the functioning of the serotonin system in the brain.

Question 10

explain decision-making systems in explaining OCD

Answer 10

Some cases of OCD seem to be associated with impaired decision making. This in turn may be associated with the abnormal functioning of the lateral side of the frontal lobes of the brain

Question 11

AO3- good supporting evidence

Answer 11

One of the best sources of evidence for the importance of genes is twin studies. Nestadt et al. reviewed previous twin studies and found that 68% of identical twins shared OCD as opposed to 31% of non-identical twins. This strongly suggests a genetic influence on OCD.

Question 12

AO3- too many candidate genes

Answer 12

Although twin studies strongly suggest that OCD is largely under genetic control, psychologists have been much less successful at pinning down all the genes involved. One reasons for this is because it appears that several genes are involved and that each genetic variation only increases the risk of OCD by a fraction. The consequence is that a genetic explanation is unlikely to ever be very useful bc it provides little predictive value

Question 13

AO3- we shouldnt assume that neural mechanisms causes OCD

Answer 13

There is evidence to suggest that various neurotransmitters and structures of the brain do not function normally in patients with OCD. However, this is not the same as saying that this abnormal functioning causes OCD. These biological abnormalities could be a result of OCD rather than its cause.