Behavior and Molecular Genetics of Personality Disorders

The purpose of this chapter is to provide an overview of the behavior and molecular genetics of personality disorder. We begin with a thorough review of findings from the field of behavior genetics of personality pathology, including univariate twin studies, multivariate twin studies, and new models of gene–environment interplay. We then discuss the molecular genetics of personality pathology, including a consideration of candidate gene analysis, linkage analysis, and genome-wide association studies. We focus in particular on research concerning antisocial personality disorder (including antisociality and aggression), borderline personality disorder, schizotypal personality disorder, Cluster B and C personality disorders, and normal personality traits. We then provide a discussion of challenges and future directions with respect to behavior and molecular genetic research. We conclude the chapter with a discussion of the implications of this research for the forthcoming fifth edition of the American Psychiatric Association’s diagnostic manual.

Avoidant Personality Disorder, Traits, and Type

In this chapter, the evolution of the avoidant personality disorder (AVPD) diagnosis, its current status, and future possibilities are reviewed. AVPD is a chronic and enduring condition involving a poor sense of self and anxiety in social situations, and it is marked by fears of rejection and a distant interpersonal stance. AVPD may be conceptualized at the severe end of a continuum of social anxiety. In the extreme, traits, mechanisms, and symptoms become integral to chronic dysfunction in personality and interpersonal style. While AVPD is a valid diagnostic construct, the optimal organization of AVPD criteria for the diagnosis, and the relationship of avoidant personality traits to anxiety, remain to be determined.

Psychodynamic Models of Personality Disorders

This chapter provides an overview of psychodynamic approaches to personality pathology and their core assumptions, and it reviews empirical research supporting these approaches. It also includes a review of contemporary psychodynamic approaches to classification, diagnosis, and treatment of personality disorders. Finally, a summary of findings concerning the effectiveness of psychodynamic treatments for personality disorder is provided.

Psychopathy

Psychopathy refers to the personality disposition to charm, manipulate, and ruthlessly exploit other persons. Psychopathic persons are lacking in conscience and feeling for others; they selfishly take what they want and do as they please without the slightest sense of guilt or regret. Psychopathy is among the oldest and arguably the most heavily researched, well-validated, and well-established personality disorder. Yet it has only indirect, informal entry in the DSMs. This chapter discusses traditional alternative conceptualizations of psychopathy, emphasizing in particular the influential and heavily researched Psychopathy Checklist-Revised. Discussed as well is the existing research concerning the epidemiology, etiology, course, treatment, and biological aspects of psychopathy, as well as its implications for DSM-5.

Assessment of Personality Disorders and Related Traits: Bridging DSM-IV-TR and DSM-5

The assessment of personality disorders and related traits is at an important crossroads with the imminent release of DSM-5. In this chapter we first review assessment techniques and measures as they pertain to the DSM-IV-TR personality disorders and pathological personality traits, focusing in particular on the many self-report inventories and semistructured interviews that have been developed. Second, we discuss the proposed changes to the diagnosis of personality disorder in DSM-5, which are substantial, and their ramifications for the assessment of personality disorder, including the (now abandoned) proposal to replace explicit diagnostic criterion sets with a prototype matching technique, the proposal to delete and/or shift a number of diagnoses from the personality disorders section, the provision of a new dimensional trait model of personality pathology, and the provision of new rating of impairment pertaining to self and interpersonal functioning.

The Death of Histrionic Personality Disorder

Histrionic personality disorder (HPD) is a diagnosis in the Diagnostic and Statistical Manual of Mental Disorders, text revision (DSM-IV-TR) and the International Classification of Diseases, tenth edition (ICD-10). The first section of this chapter defines HPD and discusses its history, starting with hysteria. The emphasis of this section is the documentation that HPD is a dying disorder that has generated little clinical or research interest as shown by the small empirical journal literature and the minimal textbook coverage. The second section of the chapter discusses the issues associated with the demise of HPD. These issues are (1) the belief that HPD is a sex-biased diagnosis, (2) the apparent failure of HPD to carve out a descriptively unique syndrome, (3) the associated loss of influence of psychoanalytic thinking in psychiatry and psychology, and (4) current efforts to overhaul the personality disorders in the upcoming DSM-5 by introducing a hybrid model and deleting categorical diagnoses with less clinical and/or empirical support.

Dialectical Behavior Therapy of Borderline and Other Personality Disorders

Dialectical behavior therapy (DBT) is a form of cognitive-behavioral therapy that draws on principles from Zen practice, dialectical philosophy, and behavioral science, and it is based on a biosocial model of borderline personality disorder. The treatment has four components—individual therapy, group skills training, telephone coaching, and therapist consultation team—and it progresses through four stages, depending on the client’s level of disorder. In the current chapter, we expand on the theory behind the treatment and the treatment structure, as well as present evidence for the efficacy of DBT from several randomized controlled trials. We also discuss implications for the use of DBT for multidiagnostic patients—including a review of a new adaptation of DBT for emotionally constricted and overcontrolled disorders.

Paranoid and Schizoid Personality Disorders

Paranoid and schizoid personality disorders are not currently proposed to be in the DSM-5 despite a long history in the clinical lexicon. This chapter reviews theoretical and empirical research on these conditions in this context. Several alternative hypotheses to the view that these constructs reflect valid syndromes are described. It is concluded that the validity of paranoid and schizoid personality disorders as unique constructs cannot be determined based on existing research and that further investigation is needed to determine their nosological status. Eliminating paranoid and schizoid as unique personality disorders in the DSM-5 would be consistent with existing evidence and the availability of multiple viable alternatives to syndromal hypotheses about paranoid and schizoid behavior.

Neurobiological Contributions

Recent advances in neurobiology have increased our understanding of the role of neurotransmitters, genetics, and brain networks in the regulation of normal behavior, individual differences in personality, and psychopathology of personality disorders. Individual differences in the regulation and organization of cognitive processes, including the experience of psychotic-like perceptual distortions and deficit symptoms, are typical in Cluster A personality disorders or schizophrenia spectrum personality disorders, such as schizotypal. Personality dimensions such as affective instability, emotional information processing, aggression, and impulsivity are typical for borderline personality disorder and other Cluster B personality disorders. A low threshold for anxiety and presence of compulsivity may contribute to the avoidant, dependent, and compulsive behaviors observed in Cluster C personality disorders. It is widely accepted that an endophenotypic approach will provide a better understanding of pathophysiological mechanisms and clarify the underlying candidate genes contributing to these behavioral dimensions, as well as susceptibility to major psychiatric illnesses.

Cognitive Therapy for Personality Disorders

Personality disorders are prevalent and common among patients presenting for treatment. Research suggests that personality disorders are associated with significant impairment and can exert a negative impact on psychological and pharmacological treatments for Axis I disorders. Despite this, treatment development and research for personality disorders has lagged behind those of Axis I disorders. The present chapter describes two major cognitive models of personality disorder—the cognitive model advanced by Beck, Freeman, and colleagues and the schema model advanced by Young and colleagues (a brief review of the dialectical behavior therapy model is also provided). The chapter presents research on both theoretical models and outlines similarities and differences between the two theoretical formulations. A description of the therapeutic relationship in cognitive therapy is also provided. The components of treatment are presented followed by a case example for purposes of illustration. Finally, the chapter summarizes the extant research on the treatment of personality disorders. Although the data are encouraging, suggesting that personality disorders are responsive to treatment, further controlled trials are still needed.