INTRODUCTION TO CLUSTER B
According to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision (DSM-IV-TR) (American Psychiatric Association [APA], 2000), the standard nosology for diagnosing psychopathology and related conditions, there are ten personality disorders classified on Axis II, with individuals identified under the broad umbrella of these disorders sorted into one of three sub-categories, or "clusters." These groupings are delineated as clusters A, B, and C, and although the categorization into sub-types provides the framework for differing symptom pictures, personality disorders are a complex and fascinating class of diagnosis (Fowler, O'Donohue, & Lilenfeld, 2007), and as a whole are among the more controversial and problematic within the diagnostic manual (Widiger, 2007). Individuals with cognitive, affective, and behavioral features related to the diagnosis of a personality disorder have deeply ingrained and pathological patterns of thoughts, feelings and behaviors that can be traced back to adolescence or early adulthood (Kraus & Reynolds, 2001); yet the body of empirical literature is scant when it comes to scientific investigations of how to treat these long-standing, characterlogical disorders found on Axis II (Callaghan, Summers, & Weidman, 2003). Notably, premature termination and poor reported outcomes are problems of particular importance and impact in working with patients diagnosed with a personality disorder (Hilsenroth et al., 1998).
There is general consensus that individuals with disordered personalities demonstrate pervasive and extensive interpersonal difficulties. Further, maladaptive and inflexible patterns of interacting with others can lead to functional impairment (APA, 2000). Due to space limitations, discussion within this paper will be specific to features of individuals with diagnostic patterns related to cluster B, which includes the diagnoses of Borderline Personality Disorder, Narcissistic Personality Disorder, Histrionic Personality Disorder, and Antisocial Personality Disorder. These cluster B "dramatic" personality disorders are all associated with pushing boundaries (Bender, 2005), and as such, clinicians must develop effective clinical formulations and make decisions on how to work with patients within the context of their particular personality organization and style (Kraus & Reynolds, 2001). The cluster B client, who may present with tendencies toward chronic self-harm, theatrical engagement in conflict, labile emotional states, dangerous antisocial sociopathy, or hyperbolic and intense displays of cognition and affect, can be challenging to manage clinically because their behaviors of interest are intrusive across domains of life functioning, including during the therapy session.
FUNCTIONAL ANALYTIC PSYCHOTHERAPY
Functional Analytic Psychotherapy, FAP (Tsai et al., 2009), is a contextual cognitive behavior therapy with roots in radical behaviorism. Briefly stated, FAP is a behavioral treatment that utilizes the therapeutic relationship to improve interpersonal difficulties (Nelson-Gray et al., 2009). FAP therapists endeavor to create vital, organic, meaningful, and dynamic therapeutic alliances (for an interpretation of FAP therapeutic alliance see Tsai et al., 2010) that progress and expand based on the therapist's conceptualization of the client's in-session behaviors, or clinically relevant behaviors (known in FAP terminology as "CRBs"). FAP conceptualizes that the mechanism of change occurs within the context of the therapeutic relationship, as the therapist shapes the client's CRBs via the process of contingent responding. The therapist pays careful attention to the communication patterns that the client exhibits, focusing on excesses and deficits in the client's interpersonal repertoire; and through the establishment and maintenance of the alliance formed via this therapeutic relationship and communication exchange, comments contingently upon the occurrence of CRBs in an effort to mold more useful skills and interactions. …