Learning Objective: to explore biological treatments for OCD

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Learning Objective: to explore
biological treatments for OCD
• ALL will be able to describe drug treatments
for OCD
• MOST will be able to analyse the mode of
action of drug treatments for OCD
• SOME will evaluate the worth of drug
treatments for OCD
DO NOW: January 2009 (c) (ii) Suggest one criticism of
the cognitive explanation for obsessive-compulsive
disorder. (2 marks)
FEEDBACK: MARK SCHEME January 2009 (c) (ii) Suggest one
criticism of the cognitive explanation for obsessive-compulsive
disorder. (2 marks)
• 1 mark for criticism, 1 for elaboration of
criticism.
• Possible answer:
• The cognitive approach focuses on internal
mental processes as an explanation and
ignores other possible causes such as
social/biological factors.
Learning Objective: to explore
biological treatments for OCD
• ALL will be able to describe drug treatments
for OCD
• MOST will be able to analyse the mode of
action of drug treatments for OCD
• SOME will evaluate the worth of drug
treatments for OCD
What do we know already about biological explanations
of OCD? Which part of the biological explanation is drug
treatment likely to focus on? Why?
Biological treatments for OCD
 BOTH of the biological treatments we will cover for OCD focus on
increasing the amount of serotonin at the synapse (the
biochemical explanation)
 SSRIs are a group of anti-depressant medications which are the
most widely prescribed drugs for anxiety disorders.
 SSRIs increase the levels of the neurotransmitter serotonin in the
brain by preventing the reabsorption of serotonin at synapses
(spaces between nerve cells). Because depression frequently
accompanies OCD, SSRIs are particularly beneficial for this anxiety
disorder.
 MAOIs are an older type of anti-depressant which are sometimes
used for those who gain no benefit from SSRIs. They prevent MAO
from destroying serotonin at the synapse.
 http://www.youtube.com/watch?v=l3FvOJExGCI
 You will watch the video and then add to your diagram to show how
SSRIs and MAOIs work
Evaluation: the good and the bad
• (+)SSRIs are easily tolerated and are safe, even for older patients.
They are not addictive and can be used in the long-term.
• (+) Drug treatment is quicker and cheaper than psychological
therapies
• (-) SSRIs cause side effects (headaches, nausea, sexual dysfunction),
there can be relapse when coming off the medication
• (-) SSRIs take 4-12 weeks before any therapeutic effect is noticed,
this, together with side effects, this can cause people to stop taking
the medication
• (-) MAOIs are effective but they are last in line to be used for
treatment due to side effects e.g. weight gain, sexual dysfunction.
• (-) A serious rise in blood pressure can occur when MAOIs are
combined with foods containing the amino acid tyramine found in
certain foods e.g. cheese, wine.
• WHAT ELSE IS WRONG WITH JUST TAKING DRUGS TO STOP
SYMPTOMS OF OCD?
This week’s homework: January 2013
PPQ
Discuss biological explanations of obsessive
compulsive disorder (OCD). Refer to
evidence in your answer. (10 marks)
Mark Scheme: creating our recipe for success
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AO1 Up to five marks for description of biological explanations of OCD. Credit can be awarded for any or
all of the following explanations:
Genetic explanation - some people are predisposed to develop the disorder as a result of inherited
familial influence. Biochemical explanation – low levels of serotonin associated with anxiety; high levels
of dopamine linked to compulsive behaviour/stereotypical movements. Physiological explanation - basal
ganglia in the brain responsible for psychomotor functions, hypersensitivity of the basal ganglia may
result in repetitive movements; linked to abnormality/excessive activity in the orbital frontal cortex.
Maximum 1 mark for simply naming/listing explanations.
Credit description of evidence up to two marks. Likely studies: McKeown and Murray (1987), Bellodi et
al. (2001), Pauls et al. (1995), Rapoport and Wise (1988), Aylward et al. (1996).
AO2 Up to five marks for discussion of biological explanations of OCD. Likely points include: the
effectiveness of biological/drug therapies and how this supports the (biochemical) explanation eg antidepressants that increase serotonin levels reduce
OCD symptoms in many patients; problem that not all sufferers respond to drug treatment; issue of
causation; treatment fallacy; contradictory evidence in brain scan studies; alternative explanations for
findings from family/twin studies such as shared environments; brain structural accounts tend to explain
repetitive behaviour but not obsessional thoughts.
Credit discussion of broader issues such as reductionism, determinism etc. Credit reasoned comparison
with alternative explanations e.g. cognitive. Only credit evaluation of the methodology used in studies
when made relevant to discussion of
the explanation. Credit use of evidence.
Maximum 6 marks if no evidence
What did the examiner say – key
mistakes made!
• Question 27
• Most answers discussed two or three explanations. In
some, key details, such as the ‘levels of serotonin’ linked to
OCD, were inaccurate.
• Some answers began to write about Selective Serotonin
Reuptake Inhibitors (SSRI) as a treatment for OCD and the
support for the ‘serotonin’ explanation, but got ‘sidetracked’ into describing different treatments rather than
focusing back on the biological explanation.
• Discussions of the basal ganglia were often well done, but
there was occasional confusion between the ‘hyperactivity’
associated with this brain region, and the cognitive notion
of ‘hypervigilance’.
Learning Objective: to explore
biological treatments for OCD
• ALL what drug treatments exist for OCD?
• MOST how do the drugs actually work, at the
level of the synapse?
• SOME what are the strengths and weaknesses
of drug treatment?
Where have you reached in your learning
today? Which questions can you answer?
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