Biologival Approach Tp Epxlaining OCD Flashcards
What is the genetic explanation of OCD
Assumes mental illness are heritable
According to the genetic explanation of ocd who is higher at risk of developing ocd
Higher risk for first degree relatives and the risk of inheriting ocd is higher in some families then others
What is identified as genes that code for vulnerability to ocd
Candidate genes
OCD is polygenic it is not caused by one single gene but by combination of genetic variations Gotham together cause significantly increased vulnerability
What genes have been linked to ocd
COMT gene - irregular dopamine levels are implicated in ocd the gene then helps deactivates dopamine
SERT gene - affects the transport of serotonin
Research support of genetic explanation for ocd
Nestadt et al - found 68% of MZ twins both Have ocd compared to 31% of DZ twins
Increases validity of the theory suggesting that ocd can be partly explained by genetics
Limitation of genetic explanation of OCD (Usefulness)
Although twin studied suggest ocd is largely under genetic control psychologist have not yet discovered alll the genes involved
This is because several genes are involved and each genetic variations increases risk of ocd
The consequence is that genetic explanation is unlikely to ever be useful because it provides predictive value
Strength of genetic explanation of ocd (twin studies)
They are a useful way to investigate the heritability of ocd
- each twin acts as a control for the others so individual difference are accounted for
- use large samples which results in roust quantitative data so research ahas good reliability
Limitation of genetic explanation of ocd (reductionism)
Ignores the role that environment plays a role in the development of ocd
What is the neural explanation of ocd
Assumes that neurotransmitters play a role in the development of the ocd
What are the two key neurotransmitters
Serotonin and dopamine
How does serotonin affect ocd
If serotonin levels are low in the frontal cortex then it is likley that someone will experience difficulty in applying logic reason and rationality t their thoughts and bevahiour
So obsessive thoughts are more likley if serotonin levels are low
Dopamine is also implicated as a neural explanation of ocd how?
Dopamine activity in the DSM has been linked to the development of compulsive behaviours
High levels of dopamine in the dsm increase compulsive reward seeking this is necessary to reduce obsessive thoughts
Strenth of neural explanations of ocd (validity)
Antidepressants such as SSRI which regulates serotonin levels have Been effective in reducing ocd symptoms
Findings support idea that irregular levels of serotonin are linked to the development of ocd which increases the validity of the theory
Strenth of neural explanation of ocd (reliability
Research into neural explanations of ocd tends to use objective, clinical methods such as fMRI scanning which is high in reliability
Limitation of neural explanations for ocd (external validity)
Not ll ocd suffers respond positively to SSRI which reduces external validity of the theory
It also questions wether the case of ocd is solely neural as SSRI cannot treat ll individuals with ocd
Limitation of neural explanations for OCD (causality
I the explanation is correlational not causal
Evidence suggest ocd patients have abnormal levels of neurotransmitters or abnormal,al brain structures but this does not mean this is what causes ocd
So other factors such as learnt behaviour or trauma may have Roe to play
So neural explanation only. A partial explanation
