Obsessive Compulsive Disorder (OCD) is a disorder of the brain and behaviour. OCD causes severe anxiety in those affected. It involves both obsessions and compulsions that take a lot of time and get in the way of important activities the person values. There are three main approaches as to why OCD may be developed including biological, cognitive and behavioural. These three approaches all have different explanations as to why an individual may develop OCD and are backed up by studies.
The first approach as to why people may develop OCD is the biological approach. The biological approach believes OCD is developed due to genetics and chemicals in the brain, that there is a physical cause to OCD. Within the biological explanation, there are a few main theories as to what may cause OCD including genetic, evolutionary, biochemical and anatomical.
Genetic influences are considered to play a role in developing OCD. Carey and Gottesman (1981) found that within identical twins, if one developed OCD the other had an 87% chance of also developing it. This also showed a pattern in fraternal twins, but with only a 47% concordance rate. Pauls et al (1995) found that first degree relatives of an OCD sufferer (who share 50% genes) had a 10.1% chance of developing OCD compared to a 1.9% chance for those with healthy relatives. Evolutionary explanations are also said to play a part in the development of OCD as OCD often involves cleaning and checking. This supports the evolutionary basis because cleaning is adaptive as it reduces the chance of contamination and disease. Checking behaviours linked to defence of resources and territory. Abed and de Pauw (1998) proposed the ‘Involuntary Risk Scenario Generating System’ which is a system of warning signal about stimuli and situations that were potentially dangerous in our evolutionary history, for example dirt may lead to disease therefore people develop OCD about washing their hands repeatedly. Szechtman and Woody (2004) suggested a security motivation system designed to detect potential dangers and prevent them turning into emergencies. This acts as an alarm detector because it is said that repeated false alarms are safer that even one failure to prepare for upcoming danger. For example, going back to check the door is locked, even though it always is, is better than not checking it once, and that time happens to be the time you forgot to lock it. They thought that it was a possibility that OCD patients find it harder to turn off their security motivation system and had an overactive warning system, leading to compulsions to relieve their anxiety. Biochemical explanations could also lead to the development of OCD. According to the serotonin hypothesis, people with OCD have reduced levels of the neurotransmitter serotonin or have a deficient serotonin metabolism. Serotonin influences both directly and indirectly, the majority of brain cells. This includes brain cells related to mood, sexual desire and function, appetite, sleep, memory and learning, temperature regulation, and some social behaviour. Dougherty et al (2002) Two classes of drug have been proven effective in treatment of OCD (SRI’s and SSRI’s), both of which increase serotonin levels. Drugs that affect neurotransmitters other than serotonin have little or no value in treating OCD. According to the anatomical explanation, certain areas of the brain don’t function the same in OCD patients as they do in healthy people. Baxter et al (1992) suggests the orbital frontal cortex is larger and there is more activity. The orbital frontal cortex is responsible for our primitive urges concerning sex, aggression, danger and hygiene. OCD symptoms also reduce when the frontal cortex is damaged (either through illness or accident).
Although there has been a lot of research done as to why biological reasons relate to the development of OCD,