Biological approach to explaining OCD

Question 1

Give two biological explanations for OCD

Answer 1

Genetic Explanations:
-Candidate genes: 5HT1-D;involved with transport of serotonin
-polygenic: Taylor (2013)-230 genes involved in OCD
-aetiologically heterogeneous - origins of OCD are different

Neural Explanations:
-Neurotransmitters- serotonin (involved in mood regulation) so long periods of lowered mood
-Brain: frontal lobe(decision making-hoarders) and parahippocampal gyrus (processing negative emotions)

Question 2

Evaluation for genetic explanations for OCD

Answer 2

-Research support: Nestadt et al (2010) found that in twins 68% of identical twins both have OCD and 31% of non-identical twins both have OCD.
Marini and Stebnicki (2012) concluded someone was 4x as likely to be diagnosed with OCD if they had a family member who was diagnosed with OCD
-Environmental risk factors:
The biological approach does not take into consideration that a person’s environment may also create an OCD in someone. Kiara Cromer et al. found that over half of her OCD patients had experienced a traumatic event.

Question 3

Evaluation for neural explanations for OCD?

Answer 3

Research support:
Antidepressants that woke solely on serotonin have been useful for reducing OCD like symptoms.
Also OCD symptoms form part of biological diseases such as Parkinsons so must also be biological in origin

Co-morbidity:
Alot of OCD patients have a co-morbidity with depression so the disturbance of serotonin in their system may be because of the depression not OCD- correlation not causation.