Description Write a 6 page analysis in which you discuss the theoretical framew …

Description Write a 6 page analysis in which you discuss the theoretical framework of the research presented in this  article Differential relations of executive functioning to borderline personality disorder presentations in adolescentsAllison Kalpakci Carolyn Ha Carla Sharp First published: 01 February 2018 https://doi.org/10.1002/pmh.1410 Citations: 4SECTIONS PDF TOOLS SHARE Abstract Borderline personality disorder (BPD) in adolescents is highly complex and heterogeneous. Within the disorder, research has suggested the existence of at least two subgroups: one with predominantly internalizing psychopathology features and one with predominantly externalizing psychopathology features. One process that may differentiate these groups is executive functioning (EF), given that poor EF is linked to externalizing psychopathology. Against this background, the current study used a multi?informant approach to examine whether adolescent patients with predominantly externalizing BPD presentations experience greater deficits in EF than adolescent patients with predominantly internalizing presentations. The sample included inpatient adolescents ages 12–17 (M = 15.26; SD = 1.51). Analyses revealed that multiple EF domains distinguished the BPD subgroups. More specifically, adolescents with externalizing presentations exhibited greater difficulties in broad domains related to global executive functioning, metacognition and behavioural regulation and specific domains related to inhibitory control, working memory, planning/organizing, monitoring and organization of materials. While this study is the first to examine EF and adolescent BPD in the context of internalizing and externalizing psychopathology, alternative approaches to examining this question are discussed. Copyright © 2018 John Wiley & Sons, Ltd. Borderline personality disorder (BPD) is a severe psychiatric condition associated with poor psychosocial outcomes. Although initially considered a disorder limited to adults, findings have established BPD in adolescence as a valid diagnostic entity warranting empirical attention.1-5 Further, research suggests that adolescents with the disorder experience similar symptomatology as their adult counterparts.6 But, much like BPD in adults, adolescent BPD is a highly complex and heterogeneous disorder. With 256 combinations of five out of the nine DSM?5 BPD criteria possible,7, 8 two individuals with BPD may exhibit highly dissimilar phenotypic presentations, rendering the investigation of the aetiology, development and treatment of the disorder a complex endeavour. One approach to addressing this complexity is to reorganize the BPD diagnosis into distinct borderline subtypes, or subgroups with distinct symptom presentations. Although research in this area is limited, findings suggest that borderline personality subtypes may exist and they appear to organize into at least two overarching groups: one with predominantly internalizing psychopathology features (i.e. traits resulting from a propensity to express distress inward (e.g. avoidant and fear?based behaviour)) and one with predominantly externalizing psychopathology features (i.e. traits resulting from a propensity to express distress outward (e.g. impulsive and antisocial behaviour)). For example, studies in adults have revealed ‘emotionally dysregulated’ vs. ‘histrionic’ subtypes, characterized by out?of?control emotions and self?harming behaviour vs. dramatic and impulsive behaviours respectively.9, 10 Further, in an unpublished manuscript, Zittel & Westen11 established the existence of two BPD subtypes—one with high degrees of externalizing symptomatology, characterized by intense anger and externalization of blame and one with greater internalizing symptomatology, characterized by dysphoric affect. To date, one study has aimed to subtype BPD in adolescents. Echoing findings from the adult studies, results from this study indicated that internalizing and externalizing subtypes exist in adolescent females with BPD.12 Other more recent studies have taken a dimensional approach and examined how the broad dimensions (rather than categories) of internalizing and externalizing psychopathology may underlie BPD. For example, in adults, Eaton, Krueger, Keyes, Skodol, Markon, Grant, & Hasin13 and Hopwood and Grilo14 embedded BPD within the internalizing and externalizing structure of common mental disorders. They suggest that individuals with BPD share the same vulnerabilities as individuals with other externalizing and internalizing disorders. In addition, James and Taylor15 found that BPD in adolescence is an indicator of both the externalizing dimension and the anxious?misery subfactor of the internalizing dimension. These dimensional approaches follow current opinion regarding cross?diagnostic dimensions, which investigates how psychological processes may cut across mental disorder more generally, dissolving categorical diagnostic categories of the Diagnostic and Statistical Manuals (e.g. Research Domain Criteria (RDoC).16, 17 These approaches are particularly relevant for the study of development psychopathology and adolescent BPD. Taken together, the findings from these studies thus far have been valuable and have reinforced what clinicians have long asserted about the possible existence of ‘borderline types’.18-20 However, only one study to date has moved beyond the descriptive level of explanation and attempted to examine whether certain underlying psychological processes21 may differentially relate to BPD subgroups, leading to their distinct symptomatic presentations. Investigating whether there are differentially acting processes would clarify the nature of the BPD subtypes, and more importantly, help advance scientific understanding of BPD aetiology and development. To investigate if an underlying psychological process is differentially relating to the BPD subgroups, one could review the BPD subtype study findings and note a pattern of BPD externalizers characterized as behaving more impulsively and erratically than BPD internalizers. Given that impulsivity is often associated with high degrees of EF?related behavioural control deficits,22, 23 it is possible that individuals with externalizing borderline psychopathology have greater difficulty with behavioural control relative to individuals with internalizing borderline psychopathology. One psychological construct that is strongly related to the aspect of behavioural control and holds promise as a potential underlying psychological process that may discriminate the internalizing vs. externalizing psychopathology BPD subtypes is executive functioning (EF), or the mental functions that regulate or control other cognitive processes.24 Components of EF include mental processes related to inhibition, shifting of attention, emotional control, initiating activity or tasks, monitoring, working memory and planning and organizing. Developmental literature indicates that adolescence represents a stage in which the prefrontal cortex, a brain region that has important implications for the development of EF25 is undergoing a number of maturational changes. EF emerges early during the first few years of life and continues to strengthen considerably throughout childhood and adolescence.26 However, to some degree, the specific EF domains differ in their developmental paths.27 EF has been examined across a number of psychiatric disorders and it has been found that deficits in EF account for a wide range of behavioural problems in disorders with externalizing psychopathology symptoms including impulsivity, social cognitive problems and emotional dysregulation.28 Given that these very behaviours often typify the BPD symptom presentation,29 researchers have begun to examine EF in relation to BPD. Findings from the EF and BPD adult studies are inconsistent, with some studies suggesting that individuals with BPD experience executive dysfunction whereas other indicate that individuals with the disorder exhibit few or no EF difficulties. For example, Gvirts et al.30 and Legris & van Reekumn31 found that adults with BPD perform poorly on tasks of working memory and attention. Additionally, Ruocco32 conducted a meta?analysis on studies that examined adult BPD and EF and found that individuals with BPD exhibit difficulty in mental processes related to planning. On the other hand, Kunert, Druecke, Sass, Herpertz33 and Sprock, Rader, Kendall, & Yoder34 found that adults with BPD did not differ from healthy controls in terms of their performance on EF tasks. In youth with BPD, the results are somewhat more consistent, with several findings suggesting that children and adolescents exhibit EF deficits more broadly.35-40 For example, Rogosch & Cicchetti39 found that children with risk factors for developing BPD displayed anomalies in the ability to control conflicting cognitions. Other studies have noted general EF deficits in youth with the disorder,35, 36, 38, 40 and one study37 did not find deficits in dual?task performance in patients with an early presentation of BPD, even within the context a stress?induced experimental paradigm. One possible explanation for the variability in the EF findings in BPD may result from the fact that the relation between EF and BPD subtypes has not yet been considered. In other words, it is possible that the variability of the EF and BPD findings may arise from the fact that EF is differentially acting upon the internalizing and externalizing symptomatology of each BPD subgroup. Given that difficulties in EF (especially EF related to behavioural dysregulation) are suggested to characterize externalizing psychopathology41-43 more so than internalizing psychopathology, adolescents with predominantly externalizing BPD presentation should exhibit greater difficulty in domains associated with EF that lead to behavioural dysregulation and impulsivity than would the adolescents with a predominantly internalizing BPD presentation. Demonstrating that EF is an important, but variable, underlying process in BPD in adolescents is important as it may not only allow for clarification of why certain individuals with BPD present with more internalizing vs. externalizing psychopathology (or vice versa) but it could (with more extensive research in this area) also provide rationale for treatments that vary the extent to which it targets certain behavioural manifestations of EF dysfunction. That is, treatment would differ in its emphasis depending on the extent to which an individual with BPD presents with internalizing vs. externalizing behaviour. In short, BPD adolescents with primarily internalizing or externalizing psychopathology may differentially respond to treatment, crucially setting the stage for the development of earlier, more targeted, clinical interventions for individuals with this disorder. Against this background, the current study took a multi?informant approach to examine whether there were differences in EF between adolescents with internalizing vs. externalizing borderline personality presentations. It was hypothesized that adolescent patients with predominantly externalizing BPD presentations would experience greater deficits in general EF than adolescent patients with predominantly internalizing BPD presentations. Given the inconsistency in findings from previous research regarding the relation between specific EF components and BPD, we opted for a more exploratory approach, and thus, no a priori predictions regarding group comparisons on specific EF components were made. To achieve our aim of employing a multi?informant approach, BPD was measured across three methods: parent?reported, self?reported and interview?based. Methods PARTICIPANTS Adolescents admitted to an inpatient psychiatric hospital were recruited for participation. Consecutive admissions (N = 483) were approached for consent, but after study exclusions and declined participation, the full sample consisted of 390 adolescent patients. Adolescents ranged between the ages of 12–17, with mean sample age = 15.35 (SD = 1.44). Average IQ scores were (M = 106.52; SD = 13.69). The majority parents of patients reported annual incomes over $200 000 and attended a 4?year college. Ninety percent of the patients were female and 85% of the sample was composed of Caucasians. In this study, only patients who met diagnostic criteria for BPD obtained from an interview?based measure of BPD and one other measure of BPD were included in the analyses. Following the subtype derivation method described in the data analytic strategy, section below resulted in N = 40 representing the BPD internalizing subtype and n = 24 representing the BPD externalizing subtype. A description of the clinical characteristics of the sample is presented in Table 1.Table 1. Sample clinical characteristicsInternalizing (n = 40)Externalizing (n = 24)n%n%DisorderDepressive3284.21664.0Bipolar25.30832.0Eating923.7000.00Externalizing1231.602080.0Anxiety3284.201664.0 Note: Psychiatric disorders diagnoses were based on the Computerized Diagnostic Interview Schedule for Children.44 Prevalence rates are exclusively with regard to positive diagnoses in which the adolescent endorsed all necessary diagnostic criteria. Depressive disorder includes major depressive disorder and dysthymia; bipolar disorder includes mania and hypomania; eating disorder includes bulimia nervosa and anorexia nervosa; anxiety disorder includes generalized anxiety disorder, separation anxiety disorder, social phobia, specific phobia, obsessive compulsive disorder, panic disorder, agoraphobia and post?traumatic stress disorder; externalizing disorder includes conduct disorder, oppositional defiant disorder and attention deficit hyperactivity disorder. Measures EXECUTIVE FUNCTION Parent?reported ratings of adolescent EF problems were obtained using the Behaviour Rating Inventory for Executive Function (BRIEF45). The BRIEF is an 86?item questionnaire in which parents rate their child or adolescent (5–18 years) on a variety of executive function behaviours in the home setting. The BRIEF provides an overall Global Executive Composite (GEC) score, which indicates overall EF impairment. In addition, two indices are derived, including the Behavioural Regulation Index (BRI) and the Metacognition Index (MI). These indices are composed of eight clinical subscales, which assess for problems in EF domains including the ability to inhibit, shift, monitor, use emotional control, initiate, working memory, plan/organize and the organization of materials. The BRI is composed of the BRIEF clinical scales of inhibit, shift and emotional control. This index assesses for the adolescent’s ability to execute inhibitory control in shifting cognitive sets and in modulating emotions and behaviour. The MI includes the BRIEF clinical scales of initiate, working memory, plan/organize, organization of materials and monitor. This index assesses the adolescent’s ability to independently manage tasks and to monitor his/her own performance. Higher T?scores on the BRIEF scales and indices represents greater executive function impairment. In the current study, the GEC, BRI and MI were used along with the eight clinical scales. Internal consistency was excellent for the full sample (? = 0.98). BORDERLINE PERSONALITY DISORDER Parent?reported BPD: Borderline Personality Features Scale for Parents (BPFSP). Parent?reported symptoms of BPD were obtained using the BPFSP that was modified from the original BPFS developed by Crick, Murray?Close, Woods.46 The BPFS was adapted by Crick et al.46 from the borderline scale of the Personality Assessment Inventory (PAI47), assessing for affective instability, identity problems, negative relationships and self?harm in youths. The BPFSP is composed of 24 items rated on a 5?point Likert scale, ranging from 1 (Not at all true) to 5 (Always true). A total score is derived by reverse scoring four items and then summing the responses for an overall score, with higher scores indicating greater levels of borderline personality features. To obtain a categorical diagnosis of BPD, adolescents were grouped into BPD versus non?BPD groups based on a cut?off score of 72, which was established by previous work on the BPFSP.48 In the present sample, internal consistency for parent?reported symptoms was excellent, with Cronbach’s alpha of 0.90. Self?reported BPD: Borderline Personality Features Scale for Children (BPFSC). This self?report version of the BPFS was administered to adolescents and was developed by Crick et al.46Adolescents were assigned to BPD and non?BPD groups based on a cut?off score of 66, which was established in a previous study on the BPFSC.48 Internal consistency for self?reported BPD symptoms was also high (? = 0.90). PAI for Adolescents (Borderline scale); PAI?A?BOR.47 The PAI?A is a dimensional measure of personality functioning in adolescents, with 264 items comprising 4 validity scales, 11 clinical scales, 5 treatment consideration scales and 2 interpersonal scales. Adequate psychometric properties have been reported for the measure.47 The BOR subscale of the PAI?A was used in this study with a T?score greater than or equal to 65 indicating clinical cut?off for BPD.47 In total, 40 items on the PAI?A assessed for symptoms of affective instability, identity problems, negative relationships and self?harm. Internal consistency for this study was excellent (? = 0.97). Interview?based assessment of BPD: Childhood Interview for DSM?IV Borderline Personality Disorder (CI?BPD49). The CI?BPD is a semi?structured interview developed specifically for use with adolescents to assess BPD diagnosis based on DSM?IV criteria. The interview was adapted from the borderline module of the Diagnostic Interview for DSM?IV Personality Disorders (DIPD?IV50). A total of 9 DSM?IV criteria were assessed. Graduate?level trained interviewers administer this interview in a setting that specializes in assessing and diagnosing BPD, directed by an expert in the development of BPD in adolescents. Interviewers underwent rigorous training on the DSM?IV/DSM?5 Section II BPD diagnosis and the CI?BPD, which included a combination of formal didactics, practice assessments and role?plays, shadowing veteran assessors, conducting the assessment with live/video observation and critique and attendance of monthly reliability meetings. Interviewers rated the aforementioned 9 symptoms using ‘0’ for absence of symptom, ‘1’ if the symptom is probably present or ‘2’ if the symptom is definitely present. A minimum of five criteria scored at a ‘2’ is required for a full diagnosis of BPD. A dichotomous score on the CI?BPD was used in the analyses to determine a diagnosis of BPD. A positive diagnosis of BPD was examined, with features or non?diagnosis recoded as ‘0’ and a full diagnosis of BPD coded as ‘1’. Confirmatory factor analysis supported a unidimensional factor structure for the CI?BPD, suggesting that the DSM?IV BPD diagnostic criteria were representative of a BPD diagnosis for adolescents.51 The study also provided evidence of good psychometric properties for the CI?BPD with adequate internal and inter?rater reliability, good convergent and concurrent validity (Sharp et al.51). Zanarini and colleagues52 have also provided support of adequate reliability for the use of this measure in a community sample of children UK. In the current study, inter?rater reliability was conducted with 12% of the sample, with two raters, with Kappa’s ranging from good (? = 0.77; p < 0.001) to very good (? = 0.89; p < 0.001) agreement. INTERNALIZING AND EXTERNALIZING PSYCHOPATHOLOGY Youth?Self Report (YSR53). At admission, adolescent patients completed a self?reported assessment of their symptoms using the YSR.53 This broad?band assessment of psychopathology has been standardized and well normed in children and adolescents from 6 to 18 years of age. The YSR consists of 112 items, in which adolescents are asked to rate their symptoms on a 3?point scale ranging from (0) not true, (1) somewhat or sometimes true, to (2) very or often true, for the past 6 months. Two broader scales of internalizing and externalizing problems include eight syndrome scales including anxious/depressed, withdrawn/depressed, and somatic complaints subscales for the Internalizing problem scale, and rule?breaking and aggressive behaviour subscales comprise the Externalizing problem scale. T?scores greater than or equal to 65 indicated clinical levels of psychopathology. The internalizing and externalizing scales were used to obtain the BPD internalizing and externalizing subtypes in this study. More details are provided in the results section in regard to how groups were derived. PROCEDURES Approval for this study was sought and obtained from local institutional review boards. On admission day, research staff met with families to provide informed consent and assent to consecutively admitted adolescents to an inpatient unit of a tertiary care hospital. Adolescent patients completed assessments during the first 2 weeks of their hospitalization, and parents completed measures within the first week of their adolescent's stay. Trained research coordinators and clinical psychology graduate students administered self?reported assessments and conducted interviews with adolescent patients. The Principal Investigator for the study met monthly with the research team to review interview?based assessments for reliability and training. Data analytic strategy It is important to note that a number of statistical analysis approaches were considered for the current study. As previously mentioned, one such approach that has more recently gained traction as a viable and sophisticated statistical method is factor analysis. In this approach, constructs underlying a set of interrelated variables are extracted. While such approaches are now mainstream, they require large sample sizes13, 15, 54 and therefore our relatively small sample size is incompatible with this statistical technique. Second, traditional bivariate approaches have yielded findings of significant clinical utility and applicability,9, 10 and we believe, that in tandem with newer more complex statistical methods, these traditional approaches can continue to serve as valuable investigative tools and contribute to empirical literature. MULTI?INFORMANT DERIVATION OF BPD INTERNALIZING AND EXTERNALIZING SUBTYPES A multi?informant approach was used to ascertain BPD diagnoses with three methods of assessment employed to derive BPD subtypes. These include (1) adolescent self?reported symptoms using the PAI?BOR and the BPFS?C; (2) interview?based assessment of BPD using the CI?BPD and (3) parent?reported BPD symptoms using the BPFSP. The process for deriving BPD subtypes across the three methods was conducted as follows. First, adolescents with a BPD diagnosis were selected from the sample. In this study, adolescents were considered to have a BPD diagnosis if they met criteria on the interview?based measure plus one other measure of BPD. More specifically, these adolescents were required to (1) meet criteria for BPD on the CI?BPD (i.e. at least five out of the nine BPD criteria met49) and (2) meet clinical cut?off on one other BPD measure (i.e. PAI?A?BOR: a T?score greater than or equal to the clinical cut?off (T ? 6547); BPFSC: a T?score greater than or equal to the clinical cut?off (T ? 65; Chang, Sharp, & Ha, 2011) or BPFSP: a T?score greater than or equal to the clinical cut?off (T ? 72; Chang et al., 2011)). Then, the adolescents with BPD (as determined by the selection method described earlier) were divided into one of two groups: (1) BPD internalizing subtype, if the participant scored equal to or above clinical cut?off on the YSR?Internalizing Scale (T ? 65;), but did not score above clinical cut?off on the YSR?Externalizing Scale (T < 6553), or (2) BPD externalizing subtype, if the participant scored equal to or above clinical cut?off on the YSR?Externalizing Scale (T ? 6553) but did not score above clinical cut?off on the YSR?Internalizing Scale (T < 6553). Results PRELIMINARY ANALYSES TO IDENTIFY POTENTIAL CONFOUNDING VARIABLES Prior to conducting the main study analyses, it was necessary to establish, at the bivariate level, the relation among study variables to identify potential confounding variables. First, independent samples t?tests were conducted to determine whether there were significant differences between males and females on any of the BRIEF composite, index and/or clinical scale scores. Results did not reveal significant difference on any of the BRIEF scale scores. To determine whether these sex differences on BRIEF scores would confound the BPD subtype group differences in later analyses, chi?square tests were conducted. Results revealed no significant differences in the gender breakdown of the internalizing and externalizing BPD subtypes. To examine the bivariate relations between the other main study variables, zero?order Pearson's correlations were conducted between IQ and the BRIEF composite, index and clinical scale scores. Results did not reveal a significant relation between full scale IQ and any of the BRIEF scale scores. Independent samples t?tests were conducted comparing the internalizing and externalizing BPD subtypes on age and full scale IQ. Results revealed no significant age or IQ differences across the groups. Finally, to determine the relation among all measures of BPD, zero?order Pearson's correlations were conducted. All measures were significantly related to each other. The CI?BPD diagnosis was significantly related to the BPFSC (r = 0.40, p < 0.001), the BPFSP (r = 0.16, p < 0.001) and the PAI?BOR (r = 0.49, p < 0.001). The BPFSC was significantly related to the BPFSP (r = 0.18, p <0 .001) and the PAI?BOR (r = 0.62, p < 0.001). And the BFPSP was significantly related to the PAI?BOR (r = 0.18, p < 0.001). GROUP COMPARISONS ON EF A one?way analysis of variance was conducted to compare the internalizing and externalizing subtypes with regard to parent?reported BRIEF clinical scale scores including Inhibit, Shift, Initiate, Working Memory, Plan/Organize, Emotional Control and Organization of Materials. A one?way analysis of variance was also conducted to compare the BPD internalizing and externalizing groups on parent?reported BRIEF composite summary scores of Global Executive Functioning and BRIEF indices of Behavioural Regulation and Metacognition. Results revealed that adolescents with predominantly externalizing BPD psychopathology scored significantly higher on the BRIEF GEC (F(1, 62) = 21.13, p < 0.001) as well as on BRIEF indices of Behavioural Regulation (F(1, 62) = 10.53, p = 0.002) and Metacognition (F(1,62) = 21.68, p < 0.001) than adolescents with predominantly internalizing psychopathology. Results revealed that adolescents with predominantly externalizing BPD psychopathology also scored significantly higher on the BRIEF clinical scales of Inhibit (F(1, 62) = 24.10, p < 0.001), Working Memory (F(1, 62) = 21.63, p < 0.001), Plan/Organize (F(1, 62) = 19.71, p < 0.001), Monitor (F(1, 62) = 19.82, p < 0.001) and Organization of Materials (F(1, 62) = 10.23, p = 0.002), than adolescents with predominantly internalizing BPD psychopathology. There were no significant differences between the BPD subtypes in regard to BRIEF clinical scales of Shift, Emotional Control or Initiate. See Table 2.Table 2. Comparison of mean BRIEF T?scores relative to internalizing and externalizing BPD groupsInternalizing (n = 40)Externalizing (n = 24)MSDMSDFInhibit52.63(13.19)70.58(15.68)24.00***Shift60.58(13.34)65.71(11.11)2.51Emotional control61.55(12.47)67.38(14.11)2.95Initiate63.23(12.94)68.67(9.42)3.22Working memory58.25(12.69)73.42(12.53)21.63***Plan/Organize60.38(12.92)74.58(11.45)19.71***Organization of materials57.75(12.33)66.42(6.26)10.23**Monitor59.93(10.67)72.58(11.57)19.82***Metacognition index6193(12.66)72.29(10.65)21.67***Behavioural regulation index59.55(13.16)70.67(13.45)10.53**Global executive component composite61.53(11.58)74.96(10.87)21.13*** Note: Values are mean T?scores. BRIEF, behaviour rating inventory for executive function; BPD, borderline personality disorder. ** p ? 0.01. *** p ? 0.001. Discussion The aim of the current study was to use a multi?informant approach to examine whether there were differences in EF between adolescents with internalizing vs. externalizing borderline personality presentations. Demonstrating that EF is an important, but variable, underlying process in BPD in adolescents may help clarify why certain individuals with BPD present with more internalizing vs. externalizing psychopathology (or vice versa) as well as set the stage for the development of earlier, more targeted, clinical interventions. Our study provided initial evidence for differential EF relations in adolescents with internalizing and externalizing presentations of BPD, suggesting that certain aspects of EF may distinguish adolescents with BPD presenting with predominantly internalizing or externalizing psychopathology. Specifically, adolescents with externalizing BPD presentations exhibited greater difficulties in both broad and specific domains of EF, compared with adolescents with internalizing psychopathology. That overall Global EF as well as the Metacognition and Behavioural Regulation Indices of the BRIEF mirrors previous research in neuropsychological functioning in adolescents with BPD35, 36 that has demonstrated deficits in EF more broadly in youth with the disorder. With regard to specific EF domains, adolescents with an externalizing BPD presentation were rated as having greater impairments domains of inhibitory control, working memory, planning/organizing, monitoring and organization of materials. The finding that adolescents with a predominantly externalizing BPD presentation exhibited poorer functioning in the domain of inhibitory control (i.e. the capacity to control or stop one's behaviour when appropriate) than adolescents with a predominantly internalizing presentation is consistent with research findings in the adult literature that has identified a subset of individuals with BPD with particular difficulty with inhibitory control, leading to poorer psychosocial functioning and outcomes than their more controlled counterparts.55 This finding also bolsters previous research in adults that identified subgroups of individuals with BPD who behaved in an especially impulsive or risky manner compared with other BPD subgroups.9-11 Our finding suggests that poor inhibitory control does not characterize all adolescents with the disorder, but rather, subset of those adolescents with higher levels of externalizing symptomology. It is possible that this lack of inhibitory control leads to engagement in more risky and impulsive behaviour, although this relation remains untested by the current study. This finding that adolescents with a predominantly externalizing BPD presentation were rated as having poorer working memory than adolescents with a predominantly internalizing presentation is consistent with prior work in adults demonstrating that highly impulsive individuals with BPD exhibit the most difficulty with working memory56 and suggests that perhaps working memory impairments may differentially relate to internalizing and externalizing BPD presentations. Although prior research examining the relation between working memory and BPD in adults has been unclear, with some studies reporting definitive working memory deficits in individuals with BPD,56-58 and others finding no such deficits,34, 59 our finding may bridge this gap, indicating that the heterogeneity of BPD symptomatology may be contributing to this discrepancy. Findings that adolescents with predominantly externalizing BPD presentations have greater difficulties with monitoring, planning and organizing materials may have implications for treatment with this group, as treatments focused heavily on cognitive strategies may be more challenging than those emphasizing behavioural strategies and practical solutions for the tasks of daily living. Future research should expand on these findings to clarify the differential causal effect of these specific EF impairments across BPD presentations in an effort to inform treatment decisions and promote better treatment outcomes for adolescents with BPD. Furthermore, we hope that our findings will stimulate future research on identification of BPD subgroups and other mechanisms that may differentiate them, paving the way for more tailored interventions. Specific EF components of emotional control, shift