Biological Therapies for OCD
Drug therapy. Antidepressant drugs (serotonin)
SSRI's Prozac Raunch and Jenike 1998 - effective in adults and children.
Tricyclic - Clomipramine - increasing availability of serotonin.
Not initially clear whether these anti depressant drugs were making the depressed syptoms less severe rather than obsessive symptoms. Thoren et al (1980) - clomipramine placebo in relieving obsessional syptoms. Theraputic effect was not related to the presence/absence of depressive symptoms in patient.
Other drugs that affect other neurotransmitters other than serotonin do not have a therapeutic effect in OCD.
Drugs = side effects. Strong risk of relapse when coming off medication. Foa et al (2005) Clomipramine more effective than placebo however still less effective than ERP.
Biological Therapies for OCD cont.
Psychosurgery. Only as last resort if all other treatment options have failed.
Surgery involves use of radio-frequency waves to destroy a small amount of brain tissue - disrupts a specific circuit in brain implicated in OCD - cortico-striatal circuit which includes the orbital-frontal cortex, the caudate nucleus and the thalamus.
Safest technique - anterior cingulotomy.
Less permanent techniques - vagus nerve stimulation and transcranial magnetic stimulation (TMS).
In early stages of research TMS shows promising results. Magnetic pulses are focused on the brain's supplementary motor area (SMA) - has a role in filtering out extraneous internal stimuli such as ruminations, obsessions and tics. TMS treatment - an attempt to normalise the SMA's activity so it properly filters out thoughts and behaviours associated with OCD.
Commentary: Biological Therapies
Evidence about efficacy of psychosurgery inconsistant.
Estimated that long term effectiveness in decreasing symptoms is between 25-70% on the criteria used for assessing sucess.
All of these techniques are drastic & irreversible and can cause seizures,
Ethical issues in terms of informed constent - Patients bad enough to warrent for psychosurgery may not fully understand the implications of such therapies.
Psychological Therapies for OCD
- Aims to uncover the uncoinscious conflicts in the individual that have been repressed.
- Free association
- Dream analysis
- There's been no controlled study of it's effectiveness with OCD and is not generally thought to be appropriate for people with ocd.
Behavioural Therapies for OCD
Therapist demonstrates 'fearless' behaviour. E.g. may handle an object which patient regards as contaminated. Later sessions patient asked to handle object.
Behavioural Therapies for OCD cont.
Observation has shown that for many people, the carrying out of rituals does the reverse effect of relieving anxiety.
Exposure and responce prevention (ERP) - stop the ritualistic behaviour. Exposed gradually to the fear stimulus then helped to avoid 'saftey rituals'. Relaxation taught in order to help patient cope with the high levels of physiological arousal associated with their fear.
Techniques include; verbal persuasion, continuous monitioring, engaging in alternative behaviour. Deliberate intervention wont work & leads to non-cooperation by patient. Other family members often involved in helping.
EXPOSURE may be broke into steps of anxiety in behaviour, e.g. 1(lowest)-8(heightest) to gradually ease the anxiety.
Behavioural Therapies for OCD cont.
- Challenging inappropriate thoughts (testing reality of negative expectations)
- Thought stopping: distracting patient from inapproiate thoughts by literally shouting 'STOP!' and asking them to switch their thinking to a pre-prepared thought or image. Patient eventually and gradually develops the skill of stopping their own thoughts when they threaten to overwhelm.
Commentary: Behavioural Therapies
Salkovskis and kirk (1997) reported moderate sucess for ERP although complete removal of symptoms occured in less than half of the participants and it's quite common for patients to drop out of therapy or refuse to cooperate.
Behavioural & cognitive therapies - take relatively short time ( 3-8 weeks) and have no side effects.
Pure cognitive interventions not as effective and ERP but in combination are more efective than either on it own. (van Oppen et al, 1995)