• Personality disorders are characterized by a chronic inflexible pattern of relating to the world that appears in the way a person thinks, feels, and behaves.
• A person with an untreated personality disorder is rarely able to enjoy ongoing, meaningful, and rewarding relationships with others, and any relationships they do form often have many problems and difficulties.
• This pattern consists of problematic behaviors and traits, starting early in life, observed across many different situations, over a long period of time, that cause significant distress.
• The defining features of a personality disorder are: a) rigid and distorted thinking, b) problems with emotional response patterns (feelings), c) impulse control problems/behaviors, and d) significant problems relating to and with others.
• When people have distorted ways of thinking about themselves and others and have difficulty controlling their emotions and their impulses, it will affect the way they handle conflict with others, and the way other people will react to them.

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• There are 10 Personality Disorders that are split into 3 Clusters.
• Cluster A includes Paranoid, Schizoid, and Schizotypal Personality Disorders, which share features of social awkwardness, social withdrawal and distorted thinking.
• Cluster B includes Borderline Personality Disorder, Narcissistic Personality Disorder, Histrionic Personality Disorder, and Antisocial Personality Disorder, which share problems with impulse control and emotional regulation.
• Cluster C includes Avoidant, Dependent, and Obsessive-Compulsive Personality Disorders, which share a high level of anxiety.

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For information on symptoms of Cluster A disorders
For information on symptoms of Cluster B disorders
For information on symptoms of Cluster C disorders

• There are 2 main factors that contribute to the development of a personality disorder.
• These are 1) biological factors, meaning people's genetic make-up and temperament, and 2) social and environmental factors, meaning people's life experiences, particularly early childhood experiences.
• These two areas interact in complex ways to influence the development of personality and therefore, a person's vulnerability to the development of a personality disorder.
• The influence of biology on behavior is often revealed in temperament, or the inborn personality disposition of a person. Some children are born with milder, calmer dispositions while others are more anxious and irritable.
• Traumatic or adverse childhood experiences have been identified as risk factors that increase the likelihood a personality disorder may develop. This can include physical, sexual, or emotional abuse and neglect, the death of a parent; the separation or divorce of parents; poor family communication; a harsh and controlling parenting style; or bullying.

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• Research about the treatment of personality disorders is still somewhat beginning and most of what is known about the treatment of a specific personality disorder cannot be generalized or applied to all personality disorders.
• There is little, if any, research information on treatment of Paranoid Personality Disorder, Schizoid Personality Disorder, or Schizotypal Personality Disorder. People with these disorders tend to be distrustful and avoid relationships with others, which may prevent them from seeking treatment.
• Only a few studies have been conducted on treatment of Avoidant Personality Disorder. There is some indication that cognitive-behavioral therapy can be an effective treatment.
• There is very limited research on the treatment of Narcissistic Personality Disorder. It appears that they may benefit from psychotherapy, but the data also suggests that people with this disorder are extremely likely to drop out of treatment, which makes definite research answers difficult to obtain.
• For Antisocial Personality Disorder, the general recommendation is a treatment that combines medication and psychotherapy, particularly cognitive-behavioral therapy, but experts are guarded about the prognosis for the treatment of this disorder.
• There is a large amount of research on the treatment of Borderline Personality Disorder. The high rates of self-injury and other self-destructive behaviors, combined with chaotic interpersonal relationships may cause people with this disorder to seek treatment more frequently. There is sufficient research evidence to suggest that certain types of psychotherapy, particularly transference-focused psychotherapy, dialectical behavior therapy, and mentalization-based therapy are very effective in treating Borderline Personality Disorder.
• Medications are sometimes used in the treatment of personality disorders. They don't necessarily "cure" personality disorders, but can help with some symptoms that may interfere with, slow down, or disrupt treatment.

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