Outline and evaluate biological approach to explaining OCD.
1. Evidence from technology
A01: Worry circuit. When a potential worry is detected by the orbitofrontal cortex (OFC), the
caudate nucleus in someone with OCD fails to supress it and the signal reaches the thalamus.
The thalamus sends it back to OFC and as a result there is a change in cognitive processing
and decision making.
A03: Menzies (2007) – MRI scans found similarities between OFC of individuals with OCD
and their family members. Suggests that there is a potentially inherited biological trade. Can
detect the onset of OCD on early stage – real world application.
2. The presence of certain genes can also lead to the development of OCD.
A01: COMT gene – high level of dopamine, SERT gene – low level of serotonin
A03: Billet (1998) twin studies - concordance rates MZ - 80%, DZ - 40% Support for genetic
explanation of OCD. However, not 100% other factors also play a role. Hard to separate
nature and nurture in twins.
3. Biological approach is deterministic.
A01: if you have COMT/SERT pre-determined. Ignore cognitive factors.
A03: An individual is under a lot of stress from knowing that they have the gene and there is
nothing they can do to change it. Ignoring the impact of cognitive factors is a limitation.
Obsessions. Many believe that cognitions play an important role in OCD and changing them
could change the behaviour. However, could take blame of, do not control their biology. Led
to successful drug treatments
Therefore, even though ignores free will and cognitions has led to successful treatments
4. Alternative explanations.
A01: Two-process model. Classical Conditioning: associate a “potential worry” (NS) with
negative thoughts (UCS) which leads to anxiety (UCR). Operant conditioning: the
compulsive behaviour reinforces because it temporarily removes anxiety.
A03: Exposure and prevention therapy: exposed to an environmental trigger and at the same
time are prevented from performing their compulsive behaviour. High success rates - 60-90%
of adults with OCD have improved.
An existence of alternative theories that have led to successful treatments is a weakness of
biological approach as OCD might not be a result of genes and levels if neurotransmitters.
1. Evidence from technology
A01: Worry circuit. When a potential worry is detected by the orbitofrontal cortex (OFC), the
caudate nucleus in someone with OCD fails to supress it and the signal reaches the thalamus.
The thalamus sends it back to OFC and as a result there is a change in cognitive processing
and decision making.
A03: Menzies (2007) – MRI scans found similarities between OFC of individuals with OCD
and their family members. Suggests that there is a potentially inherited biological trade. Can
detect the onset of OCD on early stage – real world application.
2. The presence of certain genes can also lead to the development of OCD.
A01: COMT gene – high level of dopamine, SERT gene – low level of serotonin
A03: Billet (1998) twin studies - concordance rates MZ - 80%, DZ - 40% Support for genetic
explanation of OCD. However, not 100% other factors also play a role. Hard to separate
nature and nurture in twins.
3. Biological approach is deterministic.
A01: if you have COMT/SERT pre-determined. Ignore cognitive factors.
A03: An individual is under a lot of stress from knowing that they have the gene and there is
nothing they can do to change it. Ignoring the impact of cognitive factors is a limitation.
Obsessions. Many believe that cognitions play an important role in OCD and changing them
could change the behaviour. However, could take blame of, do not control their biology. Led
to successful drug treatments
Therefore, even though ignores free will and cognitions has led to successful treatments
4. Alternative explanations.
A01: Two-process model. Classical Conditioning: associate a “potential worry” (NS) with
negative thoughts (UCS) which leads to anxiety (UCR). Operant conditioning: the
compulsive behaviour reinforces because it temporarily removes anxiety.
A03: Exposure and prevention therapy: exposed to an environmental trigger and at the same
time are prevented from performing their compulsive behaviour. High success rates - 60-90%
of adults with OCD have improved.
An existence of alternative theories that have led to successful treatments is a weakness of
biological approach as OCD might not be a result of genes and levels if neurotransmitters.
