the biological approach to explaining OCD

Question 1

what are the two explanations for OCD

Answer 1

the genetic explanation

the neural explanation

Question 2

what is the genetic explanation for OCD

Answer 2

One form of biological explanation is the genetic explanation Genes are involved in individual vulnerability to OCD

Lewis (11936) observed that of his OCD patients 37% had parents with OCD
21% of siblings with OCD

This suggests that OCD runs in families, although what is probably passed on from one generation to the next is a genetic vulnerability not the certainty of OCD

Question 3

what is the diathesis-stress model

Answer 3

certain genes leave some people more likely to suffer a mental disorder but it is not certain

some environmental stress (experience) is necessary to trigger the condition

Question 4

what are candidate genes

Answer 4

researchers have identified genes, which create vulnerability for OCD, called candidate genes

some of these genes are involved in regulating the development of the serotonin system
e.g. the gene 5HT-D beta is implicated in the efficiency of transport across synapses

Question 5

how many genes are involved in OCD

Answer 5

OCD is polygenetic

this means that OCD is not caused by one single gene but several genes are involved

Talylor (2013) has analysed findings of previous studies up to 230 different genes may be involved in OCD
genes that have been studied in relation to OCD include hose associated with the action of dopamine as well as serotonin, both neurotransmitter believed to have a role in regulating mood

Question 6

what are the different types of OCD

Answer 6

one group of genes may cause OCD while one group of genes may cause the disorder in another person

The term to describe this is aetiologically heterogeneous, meaning that the origin (aetiology) of OCD has different causes (heterogenous)

there is also evidence to show that different types of OCD may be the result of particular genetic variations e.g. hoarding disorder and religious obsession

Question 7

what is the neural explanation for OCD

Answer 7

genes associated with OCD are likely to affect the levels of key neurotransmitters as well as structures of the brain

These are neural explanations

Question 8

what is the role of serotonin in OCD

Answer 8

One explanation for OCD concerns the role of the neurotransmitter serotonin, which is believed to help regulate mood

neurotransmitters are responsible for relaying info from one neuron to another

if a person has low levels of serotonin then normal transmission of mood relevant info does not take place and mood and sometimes other mental processes - are affected

At least some cases of OCD may be explained by reduction in the functioning of the serotonin system in the brain

Question 9

how does OCD affect the person’s decision making skills

Answer 9

some cases of OCD, - in particular hoarding disorder - seem to be associated with impaired decision making

this in turn associated with abnormal functioning of the lateral (side its) of the frontal lobe (behind the forehead) that are res[onsible for logical thinking and decisions

there is also evidence to suggest that an area called the left parahippocampal gyrus associated with processing unpleasant emotions, functioning abnormally in OCD