The psychiatric handbook in the United States, the DSM-V, makes a distinction between clinical (mental) disorders and personality disorders.
Most of us are familiar with terms such as borderline personality, narcissistic personality, and antisocial personality (which is not shyness but sociopathy). Curiously, there’s no connection between personality theory and diagnostic criteria for personality disorders.
Part of the problem is that we tend to think of personality types, when in fact there are as many types as there are people. In reality, personality consists of traits.
As such, theories of personality disorders ought to start with scientifically verified traits and then look at ways these traits can become pathological. Instead, DSM-IV-TR defined 10 personality types, though DSM-V reduced this to 6. While DSM-V does have a greater focus on traits when diagnosing someone, the primary focus is still disordered personality types.
One problem with this is: If borderline personality is pathological, what does the healthy version of this same personality type look like? Well, there isn’t one. So a person has a personality type and a personality disorder, but neither has anything to do with the other.
It would be better to focus on how a particular personality trait, such as extraversion, can become maladaptive. For example, some people may be unable to ever be alone, while others may always want to be alone.
The most popular personality test is the Myers-Briggs, which defines 16 personality types based on 4 dichotomies. But the Myers-Briggs is pop psychology with no scientific validity, though it’s achieved an almost cult-like status.
The most widely accepted scientific personality theory is the Big Five: extraversion, agreeableness, openness, conscientiousness, and neuroticism. Each trait exists along a continuum, and as such there are limitless combinations rather than specific types.
Though the revisions to DSM-V are a step in the right direction, it fails to make the complete leap to personality traits rather than personality types. Part of the problem is that while the Big Five is a popular theory among academics, it’s not universally accepted.
Another problem with personality disorders is the overlap with mental disorders. What really is the difference between obsessive-compulsive disorder and obsessive-compulsive personality disorder? Or social anxiety and avoidant personality disorder?
Besides, it’s easier to bill insurance for a mental disorder.
A focus on personality traits rather than types, however, would eliminate much of this confusion, and might even shed some light on the interaction of personality traits and particular mental disorders.