This sounds like a previous question, but I will comment on a few points, because it is so important. Also the previous post answered from only one perspective. The point that I want to make is that classifications of anything are socially constructed. So, what is normal or abnormal differ from culture to culture. There may be a few universals, but there will be many more differences. So, I would question any and all classifications of what is abnormal behavior. I think you will come to interesting conclusions, if you go this route. One way to begin is to talk to people from different cultures and see what they view as normal and abnormal.
We’ve come a long way from former views of mental illness as “demonic possession” to a more scientific approach today.
A recent book that gives insight into how attitudes have changed is a book written by Steve Luxenberg about an aunt he didn’t know about who had been committed to a mental institution for most of her life. By today’s standards she would have been treat differently.
Briefly, there are five abnormal behavior classifications:
1. Clinical syndromes: depression, panic attacks, cognitive disorders, substance-related problems, psychotic, anxiety, sleep disorders, sexual and gender identity, eating disorders, impulse control
2. Personality disorders: paranoid, schizoid, antisocial, narcissistic, obsessive-compulsive
3. Medical conditions: chronic disease or pain, medication, impotence
4. Psychosocial and environmental problems: support group, social environment, education, occupation, housing, economic, health care, legal
5. Global assessment of functioning: For example, given the condition, how is that individual functioning in the real world?
What is normal, how does one decide who needs treatment to live a meaningful and enjoyable life? These are questions at the heart of psychology. The answer very much depends on the theory one uses. There are several theories of personality: psychodynamic, behavioral-cognitive, sociocultural, humanistic, et cetera. Each theory of personality holds an idea or definition of what is abnormal. Some insist that what psychology calls mental illness is just an alternative way of thinking (Kowalski & Westen, 2005). Consequently, there is no exact definition of abnormal. There does exist, a general consensus of common features they are often referred to as “the four D’s”. The four D’s are dysfunction, deviance, danger, and distress (Comer, 2007). None of these features alone assure abnormality or even the combination of several. Another feature or a fifth D, to be considered is duration. For example, one can suffer from severe and debilitating depression after a loss: death of a loved one, a job, divorce, et cetera. However, after time the depression should lessen and allow one to function normally.
Standardized descriptions of diagnostic categories enables clinicians and researchers to diagnose, discuss, study, and treat people with various mental disorders (American Psychological Association, 2000). The DSM-IV is an important tool for clinicians with invaluable guidelines for diagnosis of mental disorders. It provides a criterion for diagnoses to be standardized across psychology. When a person’s pattern of dysfunction reflects a classified disorder the psychologist knows that the pattern is basically the same as one that has been displayed by many other people. These classifications, specifically in the DSM-IV, have been investigated in a variety of studies. Like any other field of study psychology/psychiatry needs to have a point of reference, or a point of agreement. A common frame of reference, specifically classifications, at its very basic level allows a more organized method of study and practice. For example if one clinician called depression ABC and another XYZ it would be nearly impossible to share information and work together with a patient.