The odd/eccentric cluster, or cluster A, includes paranoid personality disorder, schizoid personality disorder, and schizotypal personality disorder where it is the only cluster A disorder to be recommended for retention in the alternative model. It is different from schizophrenia as bizarre thinking and functioning impairments are less severe, hallucinations are not present, and full-blown delusions are not present. Schizotypal personality disorder is the presence of 5 or more of the following signs of unusual thinking, eccentric behavior, and interpersonal deficits from early adulthood across many contexts. These include ideas of reference, odd beliefs or magical thinking such as belief in extrasensory perception, unusual perceptions, odd thought and speech, suspiciousness or paranoia, inappropriate or restricted affect, odd or eccentric behavior or appearance, lack of close friends, and social anxiety and interpersonal fears that do not diminish with familiarity. It is characterized by eccentric thoughts and behavior, interpersonal detachment, and suspiciousness. Some develop more severe psychotic symptoms over time and a small proportion develop schizophrenia. Similarities with schizophrenia include overlap with genetic vulnerability, deficits in cognitive and neuropsychological functioning, enlarged ventricles, less temporal lobe gray matter, neurotransmitter dysregulation, and some individuals with schizotypal personality may go on to develop schizophrenia.
Dramatic/erratic cluster, or cluster B, includes antisocial personality disorder, borderline personality disorder, histrionic personality disorder, and narcissistic personality disorders. It is characterized by rule-breaking behavior, exaggerated emotional displays, highly inconsistent behavior, and inflated self-esteem. Antisocial personality disorder is the pervasive disregard for the rights of others with aggressive, impulsive, and callous traits. Patterns of irresponsible behaviors are working inconsistently, breaking laws, being irritable and physically aggressive, defaulting on debts, being reckless and impulsive, and neglecting to plan ahead. There is little regard for truth and little remorse for misdeeds. It is 5 times more common in men and 75% also meet criteria for another disorder. Substance use is very common. BPD is common in clinical settings, very hard to treat, and associated with recurrent periods of suicidality. Impulsivity and instability in relationships and mood include gambling, reckless spending, indiscriminate sexual activity, and substance abuse. There are high levels of stress such as relationship conflicts. People cannot bear to be alone, have fears of abandonment, and chronic feelings of depression and emptiness. Suicidal behavior is common in BPD with a higher likelihood to engage in non-suicidal self-injury. Narcissistic personality disorder is a grandiose view of self with preoccupied fantasies of great success. Self-centered is the demand of constant attention, lack of empathy, feelings of arrogance, envy, entitlement, and view of themselves as superior to others. The primary goal of interaction with others is to bolster their own self-esteem. They value being admired more than gaining closeness and have a tendency to seek out high status partners. They are highly likely to be vindictive and aggressive when faced with a competitive threat or a put-down.
Avoidant personality disorder is being fearful of criticism, rejection, and disapproval with avoidance of social situations due to fear of negative feedback. There is restrain and inhibition in social situations based on feelings of inadequacy and inferiority. Beliefs of incompetence and inferiority is avoiding taking risks or trying new activities. There is high comorbidity with social anxiety disorder as there is similar genetic vulnerability. The DSM-5 criteria of avoidant personality disorder is a persuasive pattern of social inhibition, feelings of inadequacy, and hypersensitivity to criticism as shown by 4 or more of the following from early adulthood across many contexts. These are avoidance of occupational activities that involve significant interpersonal contact because of fears of criticism or disapproval, unwilling to get involved with people unless certain of being liked, restrained in intimate relationships because of the fear of being shamed or ridiculed, preoccupation with being criticized or rejected, inhibited in new interpersonal situations because of feelings of inadequacy, views self as socially inept, unappealing, or inferior, and unusually reluctant to try new activities because they may prove embarrassing. OCPD is perfectionistic. There is preoccupation with rules, details, schedules, and organization that is serious, rigid, formal, and inflexible and often to the extreme of being unable to finish projects. There is over focus on work with little time for leisure, family, and friends and reluctancy to make decisions or delegate. Compared to OCD, OCPD does not have the obsessions or compulsions of OCD and symptoms often co-occur and share genetic vulnerability. The DSM-5 criteria of OCDP is an intense need for order, perfection, and control as shown by the presence of at least 4 of the following from early adulthood across many contexts. These are preoccupation with rules, details, and organization to the extent that the point of an activity is lost, extreme perfectionism interferes with task completion, excessive devotion to work to the exclusion of leisure and friendships, inflexibility about morals and values, difficulty discarding worthless items, reluctance to delegate unless others conform to one’s standards, miserliness, rigidity, and stubbornness.