DSM-IV-TR: The Ten Personality Disorders: Cluster A
DSM-IV-TR: The Ten Personality Disorders2
As previously reviewed, there are four core features common to all personality disorders and before a diagnosis is made, a person must demonstrate significant and enduring difficulties in at least two of these four areas: distorted cognitions, emotional regulation, impulse regulation, and interpersonal functioning3. Furthermore, personality disorders are not usually diagnosed in children because of the requirement that personality disorders represent enduring problems across time. Besides the four core features associated with the general diagnostic category of personality disorders, there are 10 specific personality disorders identified in DSM-IV-TR (APA, 2000), each defined by a unique set of criteria reflecting observable characteristics associated with that disorder. In order to be diagnosed with a specific personality disorder, a person must meet the minimum number of criteria established for that particular disorder.
Furthermore, the 10 different personality disorder diagnoses can be grouped into three clusters (or groups). Each cluster represents a group of several specific personality disorders that are considered somewhat similar in terms of the cognitive, emotional, and behavioral patterns associated with each group or cluster of disorders. They are referred to as Cluster A (the "odd, eccentric" cluster), Cluster B (the "dramatic, emotional, erratic" cluster), and Cluster C (the "anxious, fearful" cluster). Oftentimes, a person can be diagnosed with more than just one personality disorder. Research has shown that there is a tendency for personality disorders of the same cluster to co-occur (Skodol, 2005). Later, this issue of co-occurrence will be discussed in great detail.
Cluster A: The Odd, Eccentric Cluster
Cluster A includes Paranoid Personality Disorder, Schizoid Personality Disorder, and Schizotypal Personality Disorders. The common features of the personality disorders in this cluster are social awkwardness and social withdrawal.
The Paranoid Personality Disorder* is characterized by a pervasive lack of trust in other people. People with this disorder assume that others are out to harm them, take advantage of them, or humiliate them in some way. They put a lot of effort into protecting themselves and keeping their distance from others. They are known to preemptively attack others whom they feel threatened by. They tend to hold grudges, are litigious, and display pathological jealously. Distorted thinking is evident: their perception of the environment includes reading malevolent intentions into genuinely harmless, innocuous comments or behavior, and dwelling on past slights. Their emotional life tends to be dominated by distrust and hostility.
People with Schizoid Personality Disorder* tend to be socially isolated and don't seem to seek out or enjoy close relationships. They almost always chose solitary activities, seem to take little pleasure in life, and appear indifferent to both criticism and praise. Emotionally, they tend to appear aloof, detached, and cold. The Schizoid Personality Disorder appears to be rather rare.
Persons with Schizotypal Personality Disorder* tend to be socially isolated, reserved, and distant. They frequently experience perceptual abnormalities, such as noticing flashes of light no one else can see, or seeing objects or shadows in the corner of their eyes and then realizing that nothing is there. People with Schizotypal Personality Disorder have odd beliefs, for instance, they may believe they can read other people's thoughts, or that that their own thoughts have been stolen from their heads. Schizotypal Personality Disorder tends to be found more frequently in families where someone has been diagnosed with Schizophrenia; a severe mental disorder with the defining feature of psychosis (the loss of reality testing). There is some indication that these two distinct disorders share genetic commonalities (Coccaro & Siever, 2005).
*The above list only briefly summarizes these individual Cluster A personality disorders. Richer, more detailed descriptions of these disorders are found in the section describing the four core features of personality disorders.
2 The exact number of disorders, and the methods for diagnosing personality disorders may change with the publication of DSM-V. Nonetheless, these descriptive categories will remain useful for understanding personality disorders. Further information about DSM V is available at http://www.dsm5.org/pages/default.aspx and http://en.wikipedia.org/wiki/DSM-V.
3 This diagnostic criterion may no longer be required in the upcoming DSM-V. Further information about DSM V is available at http://www.dsm5.org/pages/default.aspx and http://en.wikipedia.org/wiki/DSM-V.