Obsessive thinking is simply "thinking too much" about things.
A compulsion is an action you do in order to stop the obsessive thinking.
The textbook example is someone who compulsively washes their hands. This person may obsess about germs or dirt. In order to stop these thoughts they wash their hands. When the thoughts return they wash their hands again. These compulsive actions can become ritualized. Persons with OCD may believe that they must turn the light switch off exactly seven times in order to be certain that is really off.
Obsessive thinkers can get paranoid under stress. This type of paranoia is not as out-of-touch with reality as paranoid schizophrenia. It is actually the extreme end of thinking too much about things. If you think and think and think about something, you eventually think things are happening that are not really happening. Reducing or managing the stress can eliminate the paranoia in most cases.
OCD is presently treated with antidepressant medications and cognitive-behavioral psychotherapy. Some research suggests that outcomes are better if both of these techniques are employed. The disorder was not always understood in this way. Consider this excerpt from the 1970 edition of Hinsie & Campbell's Psychiatric Dictionary:
Psychoanalytically, obsessive-compulsive neurosis is interpreted as a defense against aggressive and/or sexual impulses, particularly in relation to the Oedipus complex. The initial defense is to the anal-sadistic level, but the impulses at this level are also intolerable and must be warded-off – by reaction formation, isolation, and undoing.
I don't understand it completely either. The modern DSM-IV defines OCD in the following way:
Either obsessions or compulsions:
Obsessions as defined by:
recurrent and persistent thoughts, impulses, or images that are experienced, at some time during the disturbance, as intrusive and inappropriate and that cause marked anxiety or distress
the thoughts, impulses, or images are not simply excessive worries about real-life problems
the person attempts to ignore or suppress such thoughts, impulses, or images, or to neutralize them with some other thought or action
the person recognizes that the obsessional thoughts, impulses, or images are a product of his or her own mind (not imposed from without as in thought insertion)
Compulsions as defined by:
repetitive behaviors (e.g., hand washing, ordering, checking) or mental acts (e.g., praying, counting, repeating words silently) that the person feels driven to perform in response to an obsession, or according to rules that must be applied rigidly
the behaviors or mental acts are aimed at preventing or reducing distress or preventing some dreaded event or situation; however, these behaviors or mental acts either are not connected in a realistic way with what they are designed to neutralize or prevent or are clearly excessive
At some point during the course of the disorder, the person has recognized that the obsessions or compulsions are excessive or unreasonable. Note: This does not apply to children.
The obsessions or compulsions cause marked distress, are time consuming (take more than 1 hour a day), or significantly interfere with the person's normal routine, occupational (or academic) functioning, or usual social activities or relationships.
If another Axis I disorder is present, the content of the obsessions or compulsions is not restricted to it (e.g., preoccupation with food in the presence of an Eating Disorder; hair pulling in the presence of Trichotillomania; concern with appearance in the presence of Body Dysmorphic Disorder; preoccupation with drugs in the presence of a Substance Use Disorder; preoccupation with having a serious illness in the presence of Hypochondriasis; preoccupation with sexual urges or fantasies in the presence of a Paraphilia; or guilty ruminations in the presence of Major Depressive Disorder).
The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.
(American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Washington, DC, 1994)
So far this sounds reasonably straightforward. It gets more complex. For starters some compulsive behaviors have their own diagnosis. Trichotillomania is the name for compulsive hair-pulling. To make things even more interesting there is another disorder with a name that is confusingly similar to OCD. Obsessive-compulsive personality disorder could be thought of as a milder, but more longstanding version of OCD – but that's not quite right.
Obsessive-compulsive personality disorder looks entirely different from OCD at first glance. The DSM-IV describes it this way:
A pervasive pattern of preoccupation with orderliness, perfectionism, and mental and interpersonal control, at the expense of flexibility, openness, and efficiency, beginning by early adulthood and present in a variety of contexts, as indicated by four (or more) of the following:
is preoccupied with details, rules, lists, order, organization, or schedules to the extent that the major point of the activity is lost
shows perfectionism that interferes with task completion (e.g., is unable to complete a project because his or her own overly strict standards are not met)
is excessively devoted to work and productivity to the exclusion of leisure activities and friendships (not accounted for by obvious economic necessity)
is overconscientious, scrupulous, and inflexible about matters of morality, ethics, or values (not accounted for by cultural or religious identification) is unable to discard worn-out or worthless objects even when they have no sentimental value
is reluctant to delegate tasks or to work with others unless they submit to exactly his or her way of doing things
adopts a miserly spending style toward both self and others; money is viewed as something to be hoarded for future catastrophes
shows rigidity and stubbornness
(American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.
Washington, DC, 1994)
When we call someone "anal" (short for "anal-retentive") we are referring to this disorder, rather than OCD. Like all personality disorders, this can be thought of as an extreme exaggeration of a certain personality style. We all know someone who is somewhat like this. It's only a personality disorder when it is so extreme that it gets in the way.
If you look hard you can see why these disorders have similar names. Both involve the tendency to obsess and to act compulsively. OCD is an illness that can develop at different points in life. Obsessive-compulsive personality disorder must have begun by early adulthood. It refers to a deeply imbedded personality style, rather than to a set of acute symptoms that get in the way.
Having some obsessive-compulsive personality traits can pay off. Students and employees who are "excessively devoted to work and productivity to the exclusion of leisure activities and friendships" can be very productive. This productivity is rewarded by good grades, pay raises, and advancement at work. Other aspects of life can suffer, however, if things are not in balance.
Psychotherapy and medications are used to treat OCD and trichotillomania. Psychotherapy can also be helpful to treat Obsessive-compulsive personality disorder, (with medications sometimes used as an adjunct). If these symptoms sound like your life, and if they are getting in the way, consider consulting a mental health professional in your area.