Neural expiation of OCD:

• STRENGTH:

  • Existence of some supporting evidence
  • 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.

  This suggests that biological factors (e.g. serotonin) may also be responsible for OCD
• LIMITATION:

  • Serotonin-OCD link may not be unique to OCD
  • Many people with OCD also experience clinical depression
  • Having two disorders together is called co-morbidity
  • This depression probably causes disruption to the action of serotonin
  • 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

  This means that serotonin may not be relevant to OCD symptoms