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Personality Disorders Guide


There are many types of personality disorders, all characterized by difficulty with relationships and interacting with the world.
There are many types of personality disorders, all characterized by difficulty with relationships and interacting with the world.
Sean Locke/Photodisc/Getty Images

Personality disorders affect the way a person sees and interacts with the world, from attitudes to relationships to behaviors. These disorders may be caused by a genetic predisposition or environmental factors such as the influences of early childhood, or a combination of the two.

Personality disorders are organized into three clusters:

Cluster A includes disorders that are characterized by odd or eccentric behaviors.

Cluster B includes disorders that are characterized by dramatic or erratic behaviors.

Cluster C includes disorders that are characterized by anxious or fear-driven behaviors.

Signs & Symptoms

The signs and symptoms of personality disorders differ for each cluster. People diagnosed with a disorder from Cluster A may have the following symptoms:

Paranoid Personality Disorder

  • Exaggerated belief that people are trying to exploit or malign you
  • A complete lack of trust in other people
  • Quickly and easily offended
  • Rigid, inflexible behaviors and beliefs

Schizoid Personality Disorder

  • Introverted
  • Limited range of emotions and emotional expression
  • Lack of personal relationships, indifference to social interaction

Schizotypal Personality Disorder

  • Flat emotions
  • Inability to correctly interpret events
  • Lack of intimate relationships
  • Magical thinking/belief in special mental powers
  • Social anxiety, socially withdrawn

See the next page to learn about the types of Cluster B personality disorders.


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