Obsessions
A typical person with OCD performs tasks, or compulsions, to seek relief from obsession-related anxiety. Within and among individuals, the initial obsessions, or intrusive thoughts, can vary in their clarity and vividness. A relatively vague obsession could involve a general sense of disarray or tension, accompanied by a belief that life cannot proceed as normal while the imbalance remains.
A more articulable obsession could be a preoccupation with the thought or image of someone close to them dying. A survey of healthy university students found that virtually all of them had these types of thoughts from time to time. Like these students, people with OCD do not enact or enjoy these violent thoughts
by these ideas—and by the sense that they could inexplicably possess them. Other obsessions concern the possibility that someone or something other than oneself—such as God, the Devil, or disease—will harm either the person with OCD or the people or things that the that person cares about. Some people dread entire concepts, fearing their materialization by causes that may seem implausible or indiscriminate to others. For example, a generalized fear of contamination might entail not only wariness of bodily secretions or excretions, but also apprehension toward household chemicals, radioactivity, newsprint, pets, or even soap.
Sexual obsessions may involve intrusive thoughts or images of "kissing, touching, fondling, oral sex, anal sex, intercourse, and rape" with "strangers, acquaintances, parents, children, family members, friends, coworkers, animals and religious figures", and can include "heterosexual or homosexual content" with persons of any age. As with other intrusive, unpleasant thoughts or images, most people have some disquieting sexual thoughts at times, but people with OCD may attach extraordinary significance to the thoughts. For example, obsessive fears about sexual orientation can appear to the person with OCD, and even to those around them, as a crisis of sexual identity.
The doubt that accompanies OCD leads to uncertainty regarding whether one might act on the troubling thoughts, resulting in self-criticism or self-loathing. or could feel that inanimate objects are ensouled. However, even though the person with OCD understands that their notions do not correspond with the external world, they feel that they must act as though their notions were correct. For example, an individual who engages in compulsive hoarding might be inclined to treat inorganic matter as if it had the sentience or rights of living organisms, but such an individual might find their consequent behavior irrational on a more intellectual level. However, Insel and Akiskal (1986) noted that in severe OCD, obsessions can shift into delusions when resistance to the obsession is abandoned and insight into its senselessness is lost.
Compulsions
While some with OCD perform compulsive rituals because they inexplicably feel they must, others act compulsively so as to mitigate the anxiety that stems from particular obsessive thoughts. The person with OCD might feel that these actions somehow either will prevent a dreaded event from occurring, or will push the event from their thoughts. In any case, the individual's reasoning is so idiosyncratic or distorted that it results in significant distress for the individual with OCD or for those around them.
Some common compulsions include counting specific things (such as footsteps) or in specific ways (for instance, by intervals of two) and doing other repetitive actions, often with atypical sensitivity to numbers or patterns. People might repeatedly wash their hands or clear their throats, repeatedly check that their parked cars have been locked before leaving them, turn lights on and off, keep doors shut or closed at all times, touch objects a certain number of times before exiting a room, walk in a certain routine way like only stepping on a certain color of tile, or have a routine for using stairs, such as always finishing a flight on the same foot.
People rely on compulsions as an escape from their obsessive thoughts; however, they are aware that the relief is only temporary, that the intrusive thoughts will soon come back. Some people use compulsions to avoid situations that may trigger their obsessions. Although some people do certain things over and over again, they don't necessarily perform these actions compulsively. For example, bedtime routines, learning a new skill, and religious practices are not compulsions. Whether or not behaviors are compulsions or mere habit depends on the context in which the behaviors are performed. For example, arranging and ordering DVDs or videos for eight hours a day would be expected of one who works in a video store, but would seem abnormal in other situations. Put another way, if the activity helps bring efficiency to one's life, it is probably a habit, if it interferes with one's normal enjoyment of life, it is probably a compulsion.
For some people with OCD, these tasks, along with the attendant anxiety and fear, can take hours of each day, making it hard for the person to fulfill their work, family, or social roles. In some cases, these behaviors can also cause adverse physical symptoms: People who obsessively wash their hands with antibacterial soap and hot water (to remove germs) can make their skin red and raw with
dermatitis. To others, these tasks may appear odd and unnecessary. But for the person with OCD, such tasks can feel critically important, and must be performed in particular ways. Individuals with OCD are aware that their thoughts and behavior are not rational, but they feel bound to comply with them to fend off feelings of panic or dread.
OCD without overt compulsions
OCD sometimes manifests without overt compulsions. Nicknamed "Pure-O", OCD without overt compulsions could, by one estimate, characterize as many as 50 percent to 60 percent of OCD cases. Rather than engaging in observable compulsions, the person with this subtype might perform more covert, mental rituals, or might feel driven to avoid the situations in which particular thoughts seem likely to intrude. Based on this reasoning, treatment involved banishing the "evil" from the "possessed" person through exorcism.
In the early 1910s, Sigmund Freud attributed obsessive–compulsive behavior to unconscious conflicts which manifested as symptoms.
The cognitive–behavioral model suggests that compulsive behaviour is carried out to remove anxiety-provoking intrusive thoughts. Unfortunately this only brings about temporary relief as the thought re-emerges. Each time the behaviour occurs it is negatively reinforced by the relief from anxiety, thereby explaining why the dysfunctional activity increases and generalizes (extends to other, related stimuli) over a period of time. For example, after touching a door-knob a person might have the thought that they may develop a disease as a result of contamination. They then experience anxiety, which is relieved when they wash their hands. This might be followed by the thought "but did I wash them properly?" causing an increase in anxiety once more, the hand-washing once again rewarded by the removal of anxiety (albeit briefly) and the cycle being repeated when thoughts of contamination re-occur. The distressing thoughts might then spread to fear of contamination from e.g. a chair (someone might have touched the chair after touching the door handle).
The National Institute of Mental Health estimates that more than two percent of the U.S. population has from
obsessive–compulsive disorder or OCD. Approximately 50% of men who have
obsessive–compulsive disorder, have sexual side-effects as a result of OCD, and that 37% of men who have OCD are plagued with
erectile dysfunction.
Biological
OCD has been linked to abnormalities with the neurotransmitter
serotonin, although it could be either a cause or an effect of these abnormalities.
Serotonin is thought to have a role in regulating anxiety. To send chemical messages from one neuron to another,
serotonin must bind to the receptor sites located on the neighboring nerve cell. It is hypothesized that the
serotonin receptors of OCD sufferers may be relatively understimulated. This suggestion is consistent with the observation that many OCD patients benefit from the use of
selective serotonin reuptake inhibitors (
SSRIs), a class of antidepressant medications that allow for more
serotonin to be readily available to other nerve cells.
A possible genetic mutation may contribute to OCD. A mutation has been found in the human
serotonin transporter
gene, hSERT, in unrelated families with OCD. Moreover, data from identical twins supports the existence of a "heritable factor for neurotic anxiety". Further, individuals with OCD are more likely to have first-degree family members exhibiting the same disorders than do matched controls. In cases where OCD develops during childhood, there is a much stronger familial link in the disorder than cases in which OCD develops later in adulthood. In general, genetic factors account for 45-65% of OCD symptoms in children diagnosed with the disorder. Environmental factors also play a role in how these anxiety symptoms are expressed; various studies on this topic are in progress and the presence of a genetic link is not yet definitely established.
Abnormal
brain development and subsequent malfunction may contribute to the manifestation of OCD. A miscommunication between the orbitofrontal cortex (OFC), caudate nucleus, and
thalamus may be a factor. The caudate nucleus lies between the OFC and
thalamus and ordinarily prevents signals from being returned to the
thalamus; if the caudate nucleus does not function normally the
thalamus may become hyperactive and create an unceasing cycle of activity between the OFC and the
thalamus, resulting in heightened anxiety. People with OCD evince increased
grey matter volumes in bilateral lenticular nuclei, extending to the caudate nuclei, while decreased
grey matter volumes in bilateral dorsal medial frontal/anterior cingulate gyri. OFC overactivity is attenuated in patients who have successfully responded to
SSRI medication, a result believed to be caused by increased stimulation of
serotonin receptors 5-HT2A and 5-HT2C. The striatum, linked to planning and the initiation of appropriate actions, has also been implicated; mice genetically engineered with a striatal abnormality exhibit OCD-like behavior, grooming themselves three times as frequently as ordinary mice. Recent evidence supports the possibility of a heritable predisposition for neurological development favoring OCD.
Rapid onset of OCD in children may be caused by Group A streptococcal infection, a condition identified by its acronym PANDAS. It has been suggested that PANDAS should be addressed as a possible cause of child OCD before other pharmacological remedies are attempted.
