Biological Approach to OCD & Treatments

Slide 1

• The images using brain-scanning techniques show that a person suffering from an OCD exhibits hyperactivity in the thalamus & orbital frontal cortex(OFC). There are also changes in levels of the neurotransmitter serotonin.
• Neural Explanations:
• PET scans show relatively low levels of serotonin activity in the brains of OCD patients & as drugs that increase serotonin activity have been found to reduce the symptoms of OCD.
• The orbital frontal cortex is thought to help initiate activity upon receiving impulses to act & then to stop the activity when the impulses lessens. With OCD, they may have difficulty in switching off or ignoring impulses, so that they turn into obsessions, resulting in compulsive behaviour.
• Evaluation:
• Despite the fact that research indicates there're neural differences between OCD sufferers & non-sufferers, it is still not known how these differences relate to the precise mechanisms of OCD.
• Not all sufferers of OCD respond positively to serotonin enhancing drugs, which lessens support for abnormal levels of the neurotransmitter being the sole cause of the disorder.

Slide 2

• Genetic Explanations:
• Centres on OCD being inherited through genetic transmission, with research originally centring on twin & family studies to assess whether this viewpoint is valid.
• With DNA profiling, more recent attention has been upon gene-mapping studies, which involve comparing genetic material from OCD sufferers & non-sufferers.

Slide 3

• CASE STUDY: Twin studies on OCD - Grootheest et al(2005)
• In this meta-analysis, the researchers assessed 70yrs of twin studies into OCD. In a twin study MZ(Identical) twins are compared against DZ(non-identical) twins. If the chances of both twins in MZ pairs having OCD is greater than the DZ twins; it suggests a genetic component, as MZ are 100% genetically similar while DZ is 50%.
• Aim: To see if there is any indication of the extent to which OCD is inherited & to see any difference of OCD inheritance between children & adults.
• Procedure: Involved of twin studies of 2 broad types were reviewed -
• 1.'Old Literature' - comprising studies between 1922 - 1965, where it is not known if patients would be diagnosed with the disorder under modern diagnostic criteria.
• 2.'Studies meeting modern criteria' - comprising studies where patients were diagnosed under DSM criteria.
• In all 10,034 twin pairs included in 28 twin studies formed the review.
• Findings: Where methodology & statistical analysis were deemed sufficiently objective to gain useful data, it was estimated that in children OCD symptoms are heritable; ranging from 45 to 65%. For adults, OCD symptoms are heritable ranging from 27 to 47%.
• Conclusions: Twin studies indicate a genetic component to the transmission of OCD. Heritability of OCD appears to be greater in children than among adults.
• Evaluation: Need for further properly controlled twin studies to investigate as the majority were not performed in large enough numbers or under methodological conditions sufficient.
• Need to include data from more gene mapping studies which look for similarities in genetic material in the DNA of sufferers & non sufferers.

Slide 4

• Evaluation of genetic explanations
• Although research suggests a genetic component to OCD, there must be some environmental influences upon the disorder or else the concordance rate between MZ twins would be 100%.
• As studies like Grootheest et al(2005) find, OCD originating in childhood is more genetic in nature than that originating in adulthood, suggesting there may be different types of OCD with different causes.

Slide 5

• Treatments for OCD
• Drug Therapy - Use of psychotropic drugs to alleviate the symptoms of mental disorder is a common form of biological treatment. Drugs may be used on their own or as an adjunct (such as CBT).
• Groups of psychotropic drugs include:
• Anti-anxiety drugs
• Anti-depressants drugs
• Anti-psychotic drugs
• Evaluation of drug treatments
• Generally drugs don't cure OCD but reduce obsessive thoughts & compulsive behaviours to such a level that a more normal lifestyle can be achieved.
• Side effects
• Not sure if drug treatments effective in treating OCD reduce obsessive symptoms or instead lessen the depressive symptoms that often accompany the condition.
• Other treatments includes ECT, Psychosurgery and CBT.