biological approach to explaining OCD Flashcards
define concordance rates
refers to the measure of genetic similarity
explain the findings of Lewis’ study (1936)
of his OCD patients 37% had parents with OCD, 21% siblings with OCD
suggesting OCD runs in families
explain the findings of Nesdadt’s study (2010)
found 68% MZ shared OCD as opposed to 31% DZ twins
define candidates genes
these identified as creating genetic vulnerability for OCD
define polygenic genes
OCD is caused by one particular gene, but instead a combination of genetic variations increasing vulnerability
explain the findings of Taylor’s study
230 genes may be involved OCD
what does the COMT gene lead to
compulsions
what is dopamine
a neurotransmitter which effects motivation and drive
what is the COMT gene responsible for
breaking down neurotransmitters and decreases heartrate down to normal levels and help you manage stres
why is the COMT gene an issue in OCD sufferers
COMT gene higher levels of dopamine
what is the other name for the 5-HTT gene
SERT gene
what does the SERT gene lead to in OCD sufferers
low mood
abnormal decision making
what happens to the SERT gene in OCD sufferers
lower levels of serotonin which is associated with OCD
(and depression)
give 2 examples of what different types of OCD is linked to genetic variatios
hoarding disorder
religious obession
define neural explanations
physical and psychological characteristics are determined by the behaviour of the nervous system (e.g: brain, neurons)
explain the worry circuit in someone with OCD
- worry is sent to orbital frontal cortex (ofc)
- it is then sent to the caudate nucleus (cn)
- in someone with OCD there are low levels of serotonin so the CN can’t function properly and allows the worry to continue
- and then the worry is passed onto the thalamus
- after the thalamus, the worry is then sent back to the orbital frontal cortex which brings it to the conscious mind, which then triggers another worry through the cycle and another worry until they carry out a compulsion
