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Personality disorders in children and adolescents.

Children and adolescents differ strikingly in their emerging personalities. Already by childhood, youth vary in their typical positive and negative emotions; capacities for selfcontrol and positive relationships with others; feelings of empathy and warmth versus hostility and alienation; and views of themselves, others, and their life experiences. For some youth, their typical personality patterns may begin to cause them difficulties in life; for example, their problematic personality patterns may lead them to experience high levels of distress or serious impairment in their daily lives, particularly in their relationships or selfdevelopment. These difficulties may become severe enough for some youth to be diagnosed with a personality disorder (PD); for others, the problems may not reach clinical significance, yet may still bear negative consequences. Both the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV; American Psychiatric Association [APA], 1994) and DSM-5 (APA, 2013) acknowledge that youth may experience PDs warranting treatment. The diagnostic manuals define PDs in terms of problematic cognition, affectivity, interpersonal functioning, and impulse control— all personality differences that vary in children and adolescents and that may become disturbed well before adulthood. The present chapter surveys the existing state of knowledge about PDs in the first two decades of life. Although there is far less research on PDs in childhood and adolescence than on other earlyemerging disorders, the research that does exist has made it clear that personality pathology does occur in childhood and adolescence and poses significant risks for mental health problems and impairment both concurrently and later in life (Cohen, Crawford, Johnson, & Kasen, 2005; De Fruyt & De Clercq, 2012; Freeman & Reinecke, 2007; Hill, 2008; Johnson et al., 2012; Mervielde, De Clercq, De Fruyt, & van Leeuwen, 2005; Shiner, 2007, 2009; Tackett, 2010; Tackett, Balsis, Oltmanns, & Krueger, 2009; Westen & Chang, 2000). This is an exciting time for research on PDs because researchers are finally turning their attention to the early manifestations of personality pathology and to the antecedents of adult PDs (see, e.g., the recent special issues of Clinical Psychology: Science and Practice, DeFife & Ritschel, 2013; Development and Psychopathology, Cicchetti & Crick, 2009; Journal of the Canadian Academy of Child and Adolescent Psychiatry, Biskin & Paris, 2013; Journal of Personality Disorders, Tackett & Sharp, 2014; Journal of Psychopathology and Behavioral Assessment, Tackett, 2010). Borderline PD (BPD) in youth and the childhood antecedents of antisocial PD (ASPD—e.g., conduct disorder and psychopathy) have received considerable attention, but researchers have begun to explore many of the other PDs and broader personality pathology domains in youth as well. Throughout the chapter, we adopt a developmental psychopathology perspective on PD (Cicchetti, 1993, 2013). In particular, we draw on two especially imporC H A P T E R 1 8