bio approach to OCD

• • variation in COMT gene causes a faulty COMT enzyme which regulates dopamine levels, causing high levels of dopamine
  • this excitatory neurotransmitter is involved in drive and motivation
  • high levels of dopamine causes the thalamus to be overactive and triggers it to act on smaller worries
  • This is how compulsions/compulsive behaviour develop.
• 1. faulty SERT gene causes seretonin to be rapidly reuptaken from the synapse resulting in low levels of seretonin,
  2. seretonin is a neurotransmitter involved in regulating mood and plays a key role in the operation of OFC and caudate nucleus
  3. OFC, referred to as the worry centre of the brain as it is responsible for sending worry signals to the thalamus
  4. low levels of seretonin causes OFC to malfunction and become overactive
  5. These minor worry signals (from the OFC) are usually supressed by the Caudate nucleus but in OCD, the caudate nucleus is thought to be damaged
  6. This leads to reucurring intrusive thoughts known as obsessions
• One strength of the biological approach is that there is evidence that it has led to the development of successful therapies. For example drug therapies. This works to correct neurochemical imalances eg. SSRIS increase the levels of seretonin Studies have shown that drug therapies like SSRIs can lead to significant reductions in OCD symptoms for example Somroo et al found they were more effective in reducing symptoms than placebos .Accoring to his review there a 70% success rate for patients using drug therapy.
• Because this therapy which works on the basis of regulating levels of neurotransmitters (eg.seretonin) (which in turn regulates brain areas) it strongly suggests there is a link between biological factors/neurotransmitters and OCD , supporting the validity of this theory

  + counter However it doesn't help 30% of people therefore depression can't be completely attributed to biological factors- an inetractionist approach may be the best way to explain OCD
• • Gottesman concordance rate 87% (of OCD/obsessive symptoms) MZ, 37% DZ twins.
  • support genetic component as the twins with the highest concordance rate share the most genetics.
  • concordance rate is not 100% and MZ twins share 100% of their DNA, can’t be attributed to just genetics, must be environmental factors which lead to the development of OCD.
  • criticism is the assumption only differ in terms of genetics.
  • Because MZ twins are more similar they tend to have more of a shared environment and be treated more similarly resulting in identity confusion and similar behaviour therefore this increased concordance rate could be down to enviornmental factors like how they are treated.
• The biological approach can be described as reductionist.. This is because it reduces complex behaviour down to biological factors eg. genes/nts . This can be beneficial because focusing on one aspect of biology can allow a specific cause of behaviour to be identified and treatements developed to address this cause (eg.SSRIs)
• However, it can be a problem because other factors may be ignored (such as cogntiive /environmental ) and preventing more realistic/valid explanations of behaviour and as a result, patients may be prevented from receiving more effective therapies. for example, It seems that environmental factors increase the risk of developing OCD. , Cromer found over half the OCD patients had a traumatic event in their past, and that OCD was more severe in those with more than one trauma. ) Therefore a more holistic theory is required as the biological approach only provides a partial explanation for human behaviour and an interactionst approach may be the best way