biological approach to explaining phobias

• biological approach?

  a perspective that emphasises the importance of physical processes in the body such as genetic inheritance and neural function.
• genetic explanations ?

  genes make up chromosomes and consist of DNA which codes the physical features of an organism and psychological features. genes are transmitted from parents to offspring
• neural explanations?

  view that physical and psychological characteristics are determined by the behaviour of the nervous system in particular the brain as well as individual neuron's.
• One strength of the genetic explanation for OCD ?

  P - strong evidence base.

  E - There is evidence from a variety of sources which strongly suggests that some people are vulnerable to OCD as a result of their genetic make-up. One source of evidence is twin studies. In one study Gerald Nestadt et al. (2010) reviewed twin studies and found that 68% of identical twins (MZ) shared OCD as opposed to 31% of non-identical (DZ) twins. Another source of evidence for a genetic influence on OCD is family studies. Research has found that a person with a family member diagnosed with OCD is around four times as likely to develop it as someone without (Marini and Stebnicki 2012).

  L - suggest that there must be some genetic influence on the development of OCD.
• One limitation of the genetic model of OCD ?

  P - environmental risk factors.

  E - There is strong evidence for the idea that genetic variation can make a person more or less vulnerable to OCD. However, OCD does not appear to be entirely genetic in origin and it seems that environmental risk factors can also trigger or increase the risk of developing OCD. In one study for example, Kiara Cromer et al. (2007) found that over half the OCD clients in their sample had experienced a traumatic event in their past. OCD was also more severe in those with one or more traumas.

  L - genetic vulnerability only provides a partial explanation for OCD.
• One strength of the neural model of OCD ?

  P -existence of some supporting evidence.

  E - Antidepressants that work purely on serotonin are effective in reducing OCD symptoms and this suggests that serotonin may be involved in OCD. Also, OCD symptoms form part of conditions that are known to be biological in origin, such as the degenerative brain disorder Parkinson's disease, which causes muscle tremors and paralysis (Nestadt et al. 2010), If a biological disorder produces OCD symptoms, then we may assume the biological processes underlie OCD.

  L - biological factors may also be responsible for OCD.
• One limitation of the neural model?

  P - serotonin-OCD link may not be unique to OCD.

  E - Many people with OCD also experience dinical depression. Having two disorders together is called co-morbidity. This depression probably involves disruption to the action of serotonin. This leaves us with a logical problem when it comes to serotonin as a possible basis for OCD. It could simply be that serotonin activity is disrupted in many people with OCD because they are depressed as well.

  L - serotonin may not be relevant to OCD symptoms.