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University of AmsterdamClinical Forensic Psychology Masterthesis
Supervisor UvA: Hans van der Baan Student number: 10002996 Submitted: April 10, 2016
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Primary and secondary subtypes of juvenile
psychopathy: a difference in attentional bias toward
addictive substances
Jessica A. Moreno Rojas
PRIMARY AND SECONDARY SUBTYPES OF JUVENILE PSYCHOPATHY: A DIFFERENCE IN ATTENTIONAL BIAS TOWARD ADDICTIVE SUBSTANCES
Table of contents
ABSTRACT ... 3
1.INTRODUCTION ... 3
1.1 JUVENILE PSYCHOPATHY ... 4
1.2PRIMARY AND SECONDARY PSYCHOPATHY ... 5
1.3SUBGROUPS OF PSYCHOPATHY AND SUBSTANCE ABUSE ... 6
1.4SUBSTANCE ABUSE AND ATTENTIONAL BIAS ... 6
1.5CURRENT FOCUS ... 7
2.MATERIALS AND METHODS ... 8
2.1PROCEDURE AND PARTICIPANTS ... 8
2.2MEASURES ... 9
2.3DATA ANALYTIC STRATEGY ... 12
3.RESULTS ... 12
3.2CORRELATIONS ... 13
3.3CLUSTER DERIVATION ... 13
3.4DESCRIPTION OF CLUSTERS ... 14
3.5VALIDATING CLUSTERS:MALTREATMENT AND NEGATIVE EMOTIONALITY... 15
3.6VALIDATING CLUSTERS:SUBSTANCE USE AND PROCESSING OF SUBSTANCE-RELATED STIMULI: ATTENTIONAL BIAS ... 16
4.DISCUSSION ... 17
5.REFERENCES ... 19
Primary and secondary subtypes of juvenile psychopathy: a difference in
attentional bias toward addictive substances
Jessica A. Moreno Rojas
Abstract
Background: Psychopathy is proven to be an important forensic construct highly comorbid with substance use disorders. Expanding beyond the traditional dimensions of psychopathy a further delineation of the construct is needed for a better understanding of the many aspects of psychopathy and its relation to substance misuse.
Methods: The present study examined 327 high-risk adolescents in six Dutch juvenile residential facilities, on alcohol abuse (The Alcohol Use Disorders Identification Test), cannabis abuse (The Cannabis Use Disorders Identification Test), anxiety sensitivity (The Substance Use Risk Profile Scale), attentional bias (Visual Probe Task), and psychopathic traits (Youth Psychopathic traits Inventory).
Results: Cluster analysis revealed that the construct of psychopathy is heterogeneous and that high-anxious secondary variants of psychopathic youth endorse more negative emotionality than low-anxious primary subtypes. The subtypes of juvenile psychopathy differed in their substance use, but contrary to expectations the primary subtype reported more substance use. As for attentional bias no significant differences between groups were found, although the secondary subtype displayed on average more attentional bias.
Conclusions: Results further underline the possibility that the two variants of psychopathy, both of which are high on the affective-interpersonal dimensions of psychopathy, may have different developmental pathways, with the primary being more related to drug (ab)use and the secondary being more related to negative emotionality and attentional bias.
Keywords: juvenile primary & secondary psychopathy, substance abuse, attentional bias
1. Introduction
The development of delinquent behaviour is characterized by a great heterogeneity within youth who show serious antisocial behaviours (Skeem, Poythress, Edens, Lilienfeld, & Cale, 2003). Distinct groups differ not only on the life course and the severity of the displayed antisocial behaviour, but also on the likely causal processes leading to their antisocial behaviour (Frick & Viding, 2009). As a result, specifying methods for distinguishing among the different subgroups of antisocial individuals, and specifically distinguishing their developmental trajectories of antisocial behaviour, has attracted much interest. Rather than solely focusing on the behavioural outcomes and following the principle of equifinality (multiple aetiological/developmental pathways can lead to similar outcomes), a more thorough understanding of antisocial behaviour in youth is likely to result from studying the various developmental pathways that lead to delinquent behaviour (Kotler & McMahon, 2005). In this context, there has been an increasing interest in exploring psychopathic traits in juvenile populations, in particular because the presence or absence of these traits may help to identify unique aetiological pathways in the development of criminal behaviour and other negative outcomes.
1.1 Juvenile Psychopathy
Historically, psychopathy has been described as a stable personality disposition, which can be identified by a cluster of specific interpersonal, affective and antisocial traits and behaviours (Hare & Neumann, 2003). On the interpersonal level, psychopathic individuals display glibness/superficial charm, a grandiose sense of self worth, pathological lying and conning/manipulative behaviour. Affectively, they are characterized by a lack of remorse or guilt, callous/lack of empathy and shallow affect. Both the interpersonal and the affective dimension are closely related to a socially deviant lifestyle that includes a parasitic lifestyle, poor behavioural control, lack of realistic, long-term goals, impulsivity, irresponsibility, failure to accept responsibility for own actions and criminal versatility (Hare & Neumann, 2009).
Several factors have led to an increasing interest in the topic of child and adolescent psychopathy. First, psychopathic traits have been strongly associated with aggressive and criminal behaviour in adult populations. This association has prompted interest in whether aggression, antisocial behaviour and violence in high-risk youth might be explained by similar personality correlates (Perez, 2012; Asscher et al., 2011). Second, due to the negative outcomes associated with psychopathy and the pessimistic view that psychopathy in adulthood seems to be unmalleable by treatment, the early identification of these particular traits seem to be essential (Rosenbaum, Lee, & Lester, 2009; Shine & Hobson, 2000; see Salekin (2002) for a meta-analysis challenging the notion that psychopathic offenders are untreatable). Moreover, retrospective findings point to the notion that psychopathic individuals have antisocial and criminal histories that commence prior to adulthood (Lynam, Miller, Vachon, Loeber, Stouthamer-Loeber, 2009; Salekin, 2008). In consequence, it is implicitly postulated that psychopathic traits in childhood or adolescence are related to adult psychopathy. However, although systematic construct validation research revealed that childhood and adolescent psychopathy fits into the nomological network surrounding adult psychopathy (Lynam et al., 2009; Lynam & Gudonis, 2005; Edens, Skeem, & Cauffman, 2001; Lynam, 1997; Frick et al., 1994), an on-going academic debate is the concern of the stability of psychopathic traits in childhood and adolescence and the downward extension of adult measures to children and adolescents (Lynam, et al., 2009; Kotler & McMahon, 2005). These concerns arise from the theoretical considerations that a) some items measure behaviours that might actually be age-appropriate in children and adolescents (e.g., need for stimulation, impulsivity, failure to accept responsibility and thrill-seeking behaviours) and b) the DSM assertion that “the traits of a personality disorder that appear in childhood will often not persist unchanged into adult life”. Indeed, in adolescence and early adulthood, basic personality traits have shown to change (Seagrave & Grisso, 2002; Edens et al., 2001). On the other hand, Caspi and Roberts (2001) ascertained that personality forms a hierarchical structure with several characteristic traits that are positioned under the more stable basic traits. With each step down the hierarchical ladder, the behavioural outcomes associated with the core traits are more susceptible to situational and social influences, particularly during adolescence and early adulthood. Consequently, specific behavioural manifestations are likely to be far less stable over time than the contributing underlying traits. This perspective theoretically upholds findings that though juvenile psychopathy has a considerable reliability and construct validity, as r ank-order stability of psychopathic characteristics shows only moderate variation over time, it can concurrently show some important developmental differences (Caldwell, McCormick, Wolfe, & Umstead, 2012; Lynam et al., 2009; Salekin, Rosenbaum, Lee, & Lester, 2009; Lynam & Gudonis, 2005; Edens et al., 2001). In other words, the same underlying construct might be expressed differently across the lifespan development. Nonetheless, the presence of affective traits of callousness and empathy deficits are considered defining features of psychopathy. These traits and their manifestations have proved to be particularly stable throughout the lifespan (Berkhout, Gross, & Kellum, 2013; Lynam,
Charnigo, Moffitt, Raine, Loeber, & Stouthamer-Loeber, 2009; Blair, Peschardt, Budhani, Mitchell, & Pine, 2006), and are thought to distinguish youth with psychopathic symptoms from those with other behavioural disorders (Salekin et al., 2009).
Another area of current academic debate on the topic of psychopathy is the question whether criminal behaviour is a necessary feature of both adult as juvenile psychopathy as it is widely accepted that egocentricity, the lack of emotion and remorse are the only core characteristics of psychopathy (Walters, Wilson, & Glover, 2011; Gao & Raine, 2010). In 1941 Cleckley in his influential work “The mask of Sanity” already documented cases of high-functioning psychopaths, who were characterized by traits of egocentricity, superficial charm and irresponsibility, but not by arrests or convictions. It has since been argued that antisocial behaviour is the consequence of the affective-emotional impairments and should not be considered as one of the diagnostic criteria of psychopathy (Cooke & Michie, 2001).
Regardless of the debate on the stability and behavioural expressions of psychopathic traits in youth, robust findings have indicated that children with heightened psychopathic traits engaged in more delinquent behaviour, have poorer adjustment and more negative outcomes in life (Asscher et al.,
2011; Lynam et al., 2009; Salekin, 2008; Kotler, & McMahon, 2005; Laurell & Daderman, 2005). Psychopathy has therefore proven to be an important forensic construct. Still its aetiology and developmental mechanisms are not well understood, as are the reasons why psychopathy is such a strong predictor of negative behavioural outcomes.
1.2 Primary and secondary psychopathy
Psychopathy usually has been interpreted as a relatively uniform construct. However, expanding beyond the traditional dimensions of psychopathy, recent studies have focused on identifying specific subtypes of psychopathy as the multidimensional factor structure of the construct itself reflects the possibility of distinctive subgroups (Skeem et al., 2003). One other reason for identifying distinct subtypes is the observed differences in the behavioural outcomes associated with this diagnosis. Gao and Raine (2010) stated in their neurobiological model of successful and unsuccessful psychopathy that individuals with psychopathic traits might tread different criminal paths due to differences in underlying developmental mechanisms, such as brain development, physiological markers and cognition. The different developmental mechanisms differentiate behavioural expressions, but also suggest differences in symptomatology, characteristics, patterns of violence and amenability to treatment. Knowledge on the aetiological heterogeneity of the subgroups, therefore, might warrant new applications for risk assessment, management and treatment (Skeem et al., 2003).
Research on the specific subtypes has mainly been driven by the hypothesis that the callous and unemotional (CU) traits component of psychopathy, which includes affective and interpersonal characteristics, may indicate an aetiologically distinct subtype of psychopathy (Kimonis, Frick, Cauffman, Goldweber, & Skeem, 2012). One distinctive distinction within this subtype is the differentiation between ‘primary’ and ‘secondary’ psychopathy (Skeem, Johansson, Andershed, Kerr, & Loudon, 2007). Primary psychopathy is conceptualized as individuals lacking anxiety, empathy and guilt. These individuals are more deliberate in their actions than individuals with secondary psychopathy. On the other hand, Secondary psychopathy is conceptualized as individuals more vulnerable to negative emotions, such as anxiety, and to exhibit larger levels of impulsivity, hostility and aggression (Magyar, Edens, Lilienfeld, Douglas, & Poythress, 2011). It is theorized that secondary psychopathy develops primarily as a consequence of adverse environmental factors, such as parental abuse. Primary psychopathy develops from a presumed constitutional deficit, characterized by a lack of conscience (Lykken, 1995; Maygar et al., 2011). Although individuals with secondary psychopathy show higher rates of impulsivity and negative emotionality, both variants tend to also show higher rates of CU
traits. As a result, in distinguishing both subgroups of psychopathy a main focus has been the presence of negative emotionality, specifically anxiety and internalizing behaviour. Given that individuals with psychopathic traits can vary substantially in their levels of anxiety and internalizing behaviour (Kimonis et al., 2012).
1.3 Subgroups of psychopathy and substance abuse
As noted above, having a psychopathic personality has not only been linked to delinquent behaviour, but also to multiple social problems, of which substance abuse is one of the most striking (Magyar et al., 2011). Psychopathy and substance abuse tend to co-occur in the same individual (Hare & Neumann, 2009), the rates of psychopathy in those with a substance abuse disorder vary from 5 to 40% (Crocker et al., 2005), and reversibly, individuals with psychopathic traits also demonstrate higher prevalence rates of alcohol and drug misuse (Edens & McDermott, 2010; Smith & Newman, 1990). The mechanism underlying this relationship is not clearly understood. As both substance abuse and psychopathy are well-known risk factor for delinquent behaviour, it is important to understand which underlying variables may contribute to the co-occurrence of psychopathy and substance abuse.
The personality domain of negative emotionality, of which anxiety sensitivity is a core feature, may be integral in playing a role in how psychopathic heterogeneity in behavioural outcomes is conceptualized. A strong relationship between the personality traits related to negative emotionality and substance misuse have been demonstrated (Gudonis et al, 2009). Indeed, individuals high in negative emotionality seem to engage in more drinking and drug use behaviour than individual lacking high levels of this trait. As negative emotionality is a core distinction in primary and secondary psychopathy, the construct of negative emotionality may be underlying the differences in interaction of psychopathy and substance abuse, and thus a common aetiological factor might be identified. When drug and alcohol problems were included as variables in the broader externalizing dimension, the secondary psychopathic subgroup obtained significantly higher mean scores on this dimension than the primary psychopathic subgroup (Polythress et al, 2010). Results were interpreted as an indication for underlying causal factors responsible for such abuse and that individuals with primary psychopathy are less prone to the use of alcohol and other drugs than individuals with secondary psychopathy. Therefore, negative emotionality seems to play a critical role in how psychopathic subtypes relate to substance use, with a strong relationship between negative affect and substance abuse being particularly evident among secondary psychopathy. Consistent with these hypotheses, empirical finding has demonstrated stronger associations between substance use behaviours and features of secondary psychopathy relative to primary psychopathy (Patrick, Hicks, Krueger, & Lang, 2005; Lynam, Whiteside, & Jones, 1999).
1.4 Substance abuse and Attentional Bias
As research has largely supported the presence of two variants of psychopathy in samples of adults and adolescents and differences in substance abuse in these two variants, one significant shortcoming of this research is the lack of comparisons between these different groups on the cognitive consequences of substance abuse; especially on their processing of substance-related stimuli. Consequences that are likely to occur as substance abuse can evolve into addiction. The development of addiction involves a transition from casual to compulsive patterns of substance use. This transition to addiction is accompanied by many substance-induced neuroadaptations (Robinson & Berridge, 2003). But not only do substances change the brain, they thereby change some psychological functions. The
most striking of these psychological changes seems to be a sensitization to the incentive motivational effects of substances and substance-related stimuli as explained by the incentive-sensitization (IS) theory of Robinson & Berridge (1993). The central principle of the IS theory is that repeated administration of a substance of abuse produces a dopaminergic response in the nucleus accumbens-related brain systems. These brain circuits normally function to attribute incentive salience to reward cues. These systems transform ordinary stimuli into incentive stimuli. Cues therefore become more attractive and able to trigger an urge to pursue and consume their reward (Robinson, Robinson, & Berridge, 2013). As a consequence, with each new administration these neural circuits may become enduringly hypersensitive (or “sensitized”) to specific substance effects and to substance-associated stimuli. This process causes the substance to be perceived as particularly salient and to acquire strong motivational properties, so that obtaining and self-administering the substance becomes an important goal (Field & Cox, 2008; Field, Eastwood, Bradley, & Mogg, 2006). Consequently, a strong subjective craving for the substance develops. Through classical conditioning, a substance-related cue ‘acquires incentive-motivational properties, grabs attention and becomes attractive and wanted, and thus guides behaviour to the incentive’ (Robinson and Berridge, 1993, p. 261). Attentional bias (AB) is a distinct psychological process that occurs as a consequence of this classical conditioning. The process of conditioning causes substance-related stimuli to elicit a conditioned response. Both processes of AB and craving are not only associated with each other, but are seen as emotional and cognitive outputs of the sensitized dopaminergic system. Both, therefore, motivate substance-seeking behaviour (Field & Cox, 2008).
The questions that the IS theory doesn’t address is why people start to use substances of abuse and why they continue doing so after a first administration. According to the theory of current concerns a current concern is a person’s motivational state between the point of becoming committed to pursuing a particular goal and the point of attaining the goal or giving up to its pursuit. Throughout the goal pursuit, the motivational state biases cognitive processing toward goal-related stimuli. Therefore, substance users have a goal of using substance (Cox, Klinger, & Fadardi, 2015; Field & Cox, 2008). Both theories and related processes seem interrelated and the processes form a mutually excitatory positive feedback loop.
As negative emotionality, in particular anxiety sensitivity, has been associated with a specific strong motive for substance use (Hopley & Brunelle 2012; Schmidt, Buckner, & Keough, 2007; Stewart, Karp, Pihl, & Peterson, 1997), individuals high on anxiety might be especially sensitive for the anxiolytic and addictive effects of some substances of abuse. With regard to the two subtypes of psychopathy, secondary variants, who are more susceptible to anxiety sensitivity, have the highest risk to not only use substances of abuse (in accordance with the theory of current concerns), but also to undergo psychological changes accumulating in an AB to substance-related stimuli (in accordance with the IS theory).
1.5 Current focus
In summary, there has been an increasing interest in exploring psychopathic traits in juvenile populations as psychopathic traits in antisocial youths indicate a distinct group who differ behaviourally, neurologically, socially, and cognitively from antisocial youths without these traits. Research suggest that there may be primary and secondary variants of psychopathy. The secondary variant shows higher rates of anxiety and has more histories of abuse. Due to their anxiety sensitivity secondary variants seem more susceptible to substance (ab)use and as a consequence might exhibit more psychological changes associated with addiction to substances of abuse, in particular display biases in the automatic processing of substance-related stimuli (attentional bias). The current study
hypothesizes that juvenile delinquents with features of secondary psychopathy report more drug (ab)use in their past and to have a stronger AB toward their substance of use, when compared to juvenile delinquents with features of primary psychopathy. The aim of the present study is twofold: (a) to validate the two typologies of psychopathy in a juvenile population and (b) to examine the relationship between the subtypes with substance use and AB in a population of Dutch youths in a juvenile detention setting. The first hypothesis is that the two subtypes of psychopathy can be identified in a juvenile population. The second hypothesis is that the two subtypes are differentially related to the use of substances of abuse in the past, and attentional bias. Specifically, youth with features of secondary psychopathy will report more substance use in the past and will have a stronger AB toward substances of use relative to juvenile delinquents with features of primary psychopathy.
2. Materials and Methods
2.1 Procedure and participants
Data for the current study were collected as part of a larger study examining the effectiveness of cognitive bias modification (CBM) above and relative to treatment-as-usual for substance abuse disorders in adolescents with severe behavioural problems residing in juvenile residential institutions in the Netherlands. Six institutions participated in this study; all offering compulsory residential psychiatric and pedagogic care and treatment to adolescents aged 12 to 23. Five of these institutions were closed youth care facilities where adolescents entered the program due to convictions for criminal activities, whilst the sixth was a residential treatment facility in which adolescents were placed under supervision or care proceeding by means of a juvenile court order. As a rule, these adolescents display serious conduct problems, frequently hold a traumatic past and stagnate in various life domains, such as school, home or social network.
Adolescents who entered, or already resided in these residential facilities between February 2014 and May 2015 were asked to participate. They completed a battery of questionnaires. Only adolescents who declared to consume alcohol and/or cannabis performed the visual probe task.
Insufficient fluency of the Dutch language was applied as an exclusion criterion. A total of 327 adolescents were included. The sample size of current study will suffice to conduct a statistical analysis of the proposed research questions.
All participants and, in case of a minor, the legal guardians were informed of the nature of the study and of the study’s potential risks and benefits. Participants voluntarily agreed to participate. Both the adolescents as well as the legal guardians were requested to sign informed consent. Participants were individually tested after two weeks of admission to the residential facility. They were assured that all data would be anonymous, confidential and that no information whatsoever would be communicated to personnel, parents or any other authority/person. In return for their efforts, participants received a small token of appreciation. The precise nature of these tokens varied per institution (e.g., personal care product or a phone-card), but all were worth roughly five euros and were in accordance with the property rules of the institutions. Participants performed the questionnaires and the visual probe task on the computer. Both the questionnaires and the visual probe task were presented according to a fixed sequence.
2.2 Measures
Clustering measuresPsychopathic traits The short version of the Youth Psychopathic Inventory (YPI) was used to measure psychopathic traits (Andershed, Kerr, Stattin and Levander, 2002). The YPI and its short version (YPI-S; van Baardewijk et al., 2010) is a self-report measure for youth aged 12 and older.
The items from the measure make up the following ten subscales: dishonest charm (e.g., "I have the ability to con people by using my charm and smile"), grandiosity (e.g., "I'm better than everyone on almost everything"), lying (e.g., "Sometimes I lie for no reason, other than because it's fun"), manipulation (e.g., "I can make people believe almost anything"), remorselessness (e.g., "To feel guilt and regret when you have done something wrong is a waste of time"), unemotionality (e.g., "I usually feel calm when other people are scared"), callousness (e.g., "I think that crying is a sign of weakness, even if no one sees you"), thrill seeking (e.g., "I like to be where exciting things happen"), impulsiveness (e.g., "I consider myself as a pretty impulsive person"), and irresponsibility (e.g., "I have often been late to work or classes in school"). Additionally, the subscales are designed to reflect three dimensions of psychopathy: Grandiose Manipulative Dimension, Callous Unemotional Dimension, and Impulsive Irresponsible Dimension. Participants respond on a 4-point Likert scale ranging from 1 ("Does not apply at all") to 4 ("Applies very well"). Several items in the scale are reverse coded so that higher scores indicate more psychopathic characteristics. The sum of the three dimension scores constitutes the total score.
The ten subscales and four summary scores generally were found to have adequate internal consistency; with Cronbach α’s ranging from .61 to .84. The dimension scores showed good internal consistency, respectively α = .82, α = .58 and α = .68. The YPI also shows adequate test-retest reliability (ICC = .74 for the total score) (Andershed, Hodgins, & Tengström, 2007; Vincent, 2006).
This instrument is theoretically based on the PCL-R (Hare, 2003). The YPI was specifically designed to address many of the challenges that make self-report of psychopathy difficult, particularly considering the fact that deceitfulness and pathological lying are core symptoms of the psychopathic personality. Additionally, the YPI measures only the personality traits associated with the psychopathic personality (the affective-interpersonal factor) rather than including the behavioural traits often associated with psychopathic behaviour. Despite the efficient nature of self-report compared with interview-based scales, van Baardewijk et al. (2010) found that the YPI could be further streamlined by the creation of a short version. The YPI-S consists of 18 items and reflect the same three-factor structure as the original YPI, while also converging highly with it (van Baardewijk et al., 2010). Further support for the YPI and the YPI-S is found in their psychometric properties, where both instruments show high internal consistency for total and factor scores (Andershed et al., 2007; Colins, Noom, & Vanderplasschen, 2012; van Baardewijk et al., 2010) and high concurrent en predictive validity (Dolan, & Rennie, 2006).
Anxiety sensitivity The Substance Use Risk Profile Scale (SURPS; Woicik, Conrod, Phil, Stewart, & Dongier, 1999) is based on a model of personality risk for substance abuse in which four personality dimensions, hopelessness, anxiety sensitivity, impulsivity, and sensation seeking, are hypothesized to differentially relate to specific patterns of substance use. The four subscales represent the four dimensions (e.g. “In stressful situations, I often fear that no one will reach me in time”, “I get frightened and feel that I am losing my mind when I cannot concentrate on the things that I need to do”, “I like doing things that frighten me a little”, and “ I would enjoy hiking long distances in wild and uninhabited territory”) and are purported to reflect different patterns of susceptibility to dependence on and abuse
of drugs with different reinforcement properties. Previous examination of the factor structure and reliability indicated that the 23-item scale loads on the four factors with good reliability for each of the subscales with adequate mean inter-item correlations (Woicik, Stewart, Pihl, & Conrod, 2009). The SURPS is typically administered in a paper/pencil or computerized format on which respondents
indicate to which they agree with statements about themselves on a 4-point Likert scale ranging from 1
("Strongly disagree") to 4 ("Strongly agree").
External criteria variables
Alcohol (ab)use The Alcohol Use Disorders Identification Test (AUDIT; Babor, Higgins-Biddle, Saunders, & Monteiro, 2001) is a ten-question self-report test developed by the World Health Organization to determine if a person's alcohol consumption may be harmful. The test was designed to be used internationally, and was validated in a study using patients from six countries. Questions 1–3 deal with alcohol consumption (e.g. “How often do you have a drink containing alcohol?”), 4–6 relate to alcohol dependence (e.g., “How often during the last year have you found that you were not able to stop drinking once you had started?”) and 7–10 consider alcohol-related problems (e.g., “Have you or someone else been injured because of drinking?”). Participants respond on 5-point rating scales ranging from 0 ("never"), 1 (“less than 1 or 2 a month”), 2 ("3 to 4 a month"), 3 ("4 or more times a week"), to 4 (“daily or almost daily”). Questions 9 and 10 require a “yes” or ‘no” answer (e.g., “Have you or someone else been injured as a result of your use of cannabis over the past 6 months?). A score of 8 or more in men (7 in women) indicates a strong likelihood of hazardous or harmful alcohol consumption. A score of 20 or more is suggestive of alcohol dependence. Sensitivities and specificities of the selected test items were computed for multiple criteria (i.e., average daily alcohol consumption, recurrent intoxication, presence of at least one dependence symptom, diagnosis of alcohol abuse or dependence, and self-perception of a drinking problem). Various cut-off points in total scores were considered to identify the value with optimal sensitivity and specificity to distinguish hazardous and harmful alcohol use. In addition, validity was also computed against a composite diagnosis of harmful use and dependence. In the test development samples, a cut-off value of 8 points yielded sensitivities for the AUDIT for various indices of problematic drinking that were generally in the mid 0.90’s. Specificities across countries and across criteria averaged in the 0.80’s.
Cannabis (ab)use The Cannabis Use Disorders Identification Test (CUDIT; Adamson & Sellman, 2003) was developed by simple modification of the AUDIT, based on the same assumption underlying current diagnostic principle of the DSM-IV, i.e. that the phenomenology of substance disorders is equivalent across the different substances. The CUDIT is a self-report test that assesses the amount of cannabis used (e.g., “How often were you “stoned” for 6 or more hours?”), symptoms of cannabis dependence (e.g., “How often during the past 6 months did you need to use cannabis in the morning to get yourself going after a heavy session?”), and cannabis-related problems (e.g., “Has a relative, friend or a doctor or other health worker been concerned about your use of cannabis or suggested you cut down over the past 6 months?”). The test contains 10 questions related to cannabis use over the past six months to which participants respond on 5-point rating scales ranging from from 0 ("never"), 1 (“less than 1 or 2 a month”), 2 ("3 to 4 a month"), 3 ("4 or more times a week"), to 4 (“daily or almost daily”). Questions 9 and 10 require a “yes” or ‘no” answer. A score of 8 or more, on a scale of 0 to 40, indicates a strong likelihood of harmful cannabis use. This cut-off generates sensitivity of approximately 73% and positive predictive value of approximately 85%.
A revised CUDIT-R was developed containing 8 items, two each from the domains of consumption, cannabis problems (abuse), dependence, and psychological features. The CUDIT-R has
shown to be a reliable and valid screening test (Adamson et al., 2010). The CUDIT-R was used for the purpose of this study.
Substance (ab)use To provide more stable measures of the substance use at large, a composite was formed with unit-weighted z scores of the constituent tests. Z scores of the AUDIT and the CUDIT were summed to create a drug use profile. Higher scores on this composite measure represent more drug use.
Negative emotionality The Brief Problem Monitor – Youth (BPM-Y) is a rating instrument for monitoring children’s functioning and responses to interventions. The BPM can also be used to compare children’s responses to different intervention and control conditions. The BPM includes items for rating Internalizing (INT), Attention (ATT), and Externalizing (EXT) problems over user-selected rating periods (e.g., 5, 7, 14, 30, 45 days). The items are drawn from the Child Behavior Checklist for Ages 6-18 (CBCL/6-18), Teacher’s Report Form (TRF), and Youth Self-Report (YSR) (Achenbach & Rescorla, 2001). This study only uses the youth self-report version of the BPM. Each item is rated 0 = not true, 1 = somewhat true, or 2 = very true. Users can add problems and/or strengths not already on the BPM, such as those that are especially targeted for change. After each item there is room for comments from the participant. The Internalizing problems subscale was used for the purpose of this study.
Maltreatment history The Childhood Trauma Questionnaire (CTQ or JTV; Bernstein & Fink, 1998) is a standardized, retrospective 28-item self-report inventory that measures the severity of different types of childhood trauma, producing five clinical subscales: Emotional Abuse, Physical Abuse, Sexual Abuse, Emotional Neglect and Physical Neglect. CTQ items are given a score of 1-5 on a five-point Likert-type scale; 1= never true, 2=rarely true, 3= sometimes true, 4= often true, 5=very often true.
The questionnaire also includes a three-item Minimization/ Denial scale indicating the potential underreporting of maltreatment. The three items are dichotomized (“never true” = 0, all other responses = 1) and summed. A total of one or greater suggests the possible underreporting of maltreatment (false negatives) (Bernstein & Fink, 1998).
The CTQ is validated for adolescent psychiatric patients (Bernstein, Ahluvalia, Pogge & Handelsman, 1997), male and female street youth (Forde, Baron, Scher & Stein, 2012) and Canadian students (Paivio & Cramer, 2004). The original CTQ consists of 70 items, but the version with 28 items is also validated for multiple populations (Bernstein et al., 2003).
Attentional bias The Visual Probe task (VPT) measured attentional bias (AB). This is a computerized reaction time task in which participants respond to probes (arrows) at two different locations on the computer screen. Each trial of the visual-probe classification task started with a blind screen for 500 ms, following a fixation cross in the middle of the screen for 500 to 1000 ms. Subsequently, two pictures -one substance-related, one neutral- were simultaneously presented left and right from the centre of the screen. This was done for 500 ms. Immediately after picture offset, an arrow replaced one of the two pictures for 4000 ms. Participants were instructed to look at the fixation cross at the start of each trial, and to classify the arrow as fast as possible by pressing the corresponding upper (for arrows pointing up) or lower button (for arrows pointing down) of a response box. To reduce the monotony of the task, the inter-trial interval varied randomly between 500 and 1000 ms. Faster responses to arrows replacing substance compared to neutral pictures indicate AB.
The pre-test (in session 1) started with 16 practice trials. Understanding of the instructions was verified followed by the 80 critical trials. After a short break the second block of 80 critical trials were performed. Only the critical trials were used for analyses. In the critical trials, 10 substance-neutral
picture pairs were each repeated eight times. For each stimulus duration probes replaced the substance picture and neutral picture equally often, and each picture type was located on the left and right of the screen equally often.
VPA scores are calculated by subtracting reaction times to probes that replaces substance-related pictures from reaction times to probes that replaced neutral pictures, such that positive scores indicate an AB. All critical trials are aggregated and median time is calculated.
2.3 Data analytic strategy
In order to overcome the loss of information due to incomplete observations with missing variable values, multiple imputation (MI) is used to address missing values of the YPI to minimize biased parameter estimates. The MI procedure replaces each missing value with a set of plausible values that represent the uncertainty about the right value to impute. These multiply imputed data sets are then analysed by using standard procedures for complete data and combining the results from these analyses. No matter which complete-data analysis is used, the process of combining results from different imputed data sets is essentially the same. This results in valid statistical inferences that properly reflect the uncertainty due to missing values. Following MI, bivariate correlations are conducted to examine the relations among study variables. Thirdly, a k-means cluster analysis will be applied to determine whether primary and secondary subtypes of juvenile psychopathy can be identified in a subsample (n = 134) of male juvenile offenders scoring high on the measure of psychopathy. To validate the resultant clusters, t tests and multivariate analyses of variance are used to compare them on theoretically relevant factors (not) used to derive them. Finally, one-way ANOVA’s will be used to compare the two subtypes and comparison group on substance (ab)use and attentional bias.
3. Results
Descriptive characteristics of study participants are reported in Table 1. Table 1
Population characteristics
N % Mean (SD) Range
Age (date of admission) 327 18.4 (2.1) 13.3 – 24.5
Male 92
Dutch cultural identity 47
YPI 310 33.61 (8.01) 18 - 56
VPT 115 12.89 (37.97) -112 - 121
CUDIT 216 12.76 (6.8) 1 - 32
AUDIT 205 7.16 (5.7) 1 - 35
SURPS (anxiety sensitivity) 320 8.43 (3.03) 5 – 19
3.2 Correlations
Data for all study variables was positively skewed. Normality could not be achieved using logarithmic or square root transformations, thus all conducted bivariate correlations between study variables are indicated by Spearman’s rho (ρ).
Bivariate correlations between study variables are presented in Table 2. As expected, AUDIT and CUDIT scores correlated significantly with each other. VPT scores did not correlate with the AUDIT and CUDIT scores, but did correlate with the substance use composite score, suggesting that attentional bias tend to increase with the use of more substances. Moreover, the same pattern was found for YPI scores which correlated not with the individual substance use test scores, but with the composite substance use score. All other correlations were insignificant.
Table 2
Correlation between study variables (N= 327) 1 2 3 4 5 6 7 8 1 AUDIT - .34** -.16 -.07 .17* .72** .08 -.11 2 CUDIT - -.19 -.08 .22** .90** .06 -.04 3 VPT - -.10 -.04 -.20* -.09 .09 4 SURPS - .10 .03 .02 .05 5 YPI - .20** -.05 -.09 6 Substance use - .09 -.07 7 Age - -.01 8 Cultural Identity - Note. * = p < .05, ** = p < .01.
3.3 Cluster derivation
Despite the fact that a growing body of research suggests that psychopathy is a dimensional trait rather than categorical, a threshold score was used to select youth with substantial psychopathic traits as the focus of this study is on at-risk juveniles with high scores on the YPI-S. Thus, the derivation of clusters of primary and secondary subtypes of psychopathy was conducted to juveniles with scores greater than 34 on the YPI-S. The YPI-S does not have an established cut-off score for classifying youth as psychopathic, nevertheless a score of 35 and above was found to correspond to a cluster of adolescent male offenders high on psychopathic traits, notably the callous-unemotional dimension, in a large sample (N = 768) (Colins et al., 2012). In this study a YPI-S total score of 35 and above was found to positively and significantly relate to externalizing problems, problems with peers and all types of offending (e.g. violent, property, and drug-related offenses).
K-means cluster analysis was performed using SPSS 22. K-means clustering is a method of vector quantization that allows the modelling of probability density functions by the distribution of prototype vectors. Therefore, k-means clustering aims to partition n observations into k clusters in which each observation belong to the cluster with the nearest mean, serving as a prototype of the cluster. Via an iterative refinement approach (more commonly 10 iterations) k-means clustering tends to find clusters of comparable spatial extent (n = 134)(https://en.wikipedia.org/wiki/K-means_clustering). Youths’ Z scores (based on the psychopathic subsample) on the total score of the YPI and the anxiety scale of the SURPS were used as clustering variables. As expected, the best fitting model was a two-cluster solution (see Figure 1). The maximum absolute coordinate change for any center was .000 after four iteration A
two cluster achieved convergence after four 4 iterations (10 iterations for a 3 cluster solution) and as both variables contributed significantly to the derivation of the cluster (YPI, F(1, 132)= 3.97, p < .05 and SURPS (anxiety sensitivity), F(1, 132) = 311.76, p < .01), the anxiety sensitivity variable had, as expected, the largest contribution (both the YPI as the SURPS (anxiety sensitivity) were highly significant (ps < .01) in a three cluster solution).
Figure 1
3.4 Description of clusters
Using t tests, the two clusters were compared on total and subscale scores of the YPI-S and the SURPS for descriptive purposes (see Table 3). The first cluster (n = 47), which was labeled ‘secondary’ reported significantly lower Affective factor scores, t(132) = 2.49, p < .01 and total scores t(132) = -1.99, p < .05 ; but not Interpersonal or Behavioural factor scores compared to the second cluster (n = 87), which was labeled ‘primary’. Moreover, the secondary subgroup (cluster 1) reported significantly greater anxiety sensitivity, t(132) = 17.66, p < .01, compared to the primary subgroup (cluster 2), but not more feelings of hopelessness, impulsivity or sensation seeking. Comparison youths were significantly less anxious, impulsive and sensation seeking than both subtypes.
Table 3
Characteristics of the ‘nonpsychotic’ comparison group, and the clustering subtypes (YPI-S > 34)
Comparison group Primary subtype Secondary subtype
(n = 186) (n = 87) (n = 47)
Age (date of admission) (SD) 18.41 (1.83) 18.08 (2.59) 18.64 (1.74)
Male 91% 94% 94%
Dutch cultural identity 45% 51% 51%
YPI total score (SD) 27.95 (4.22) 41.69 (5.65) 39.81 (4.29)
YPI Interpersonal dimension (SD) 8.56 (2.36) 13.66 (3.94) 13.30 (2.90)
YPI Affective dimension (SD) 8.77 (2.22) 13.53 (3.60) 11.98 (3.12)
YPI Behavioural dimension (SD) 10.62 (2.53) 14.51 (3.48) 14.53 (2.86)
SURPS Anxiety sensitivity (SD) 8.32 (2.99) 6.69 (1.36) 12.11 (2.19)
SURPS Hopelessness (SD) 11.83 (4.26) 11.67 (3.77) 12.09 (4.02)
SURPS Sensation Seeking (SD) 14.32 (4.10) 16.30 (3.57) 16.66 (3.70)
SURPS Impulsivity (SD) 9.24 (3.03) 11.55 (3.39) 12.40 (3.06)
Note. SD = Standard Deviation.
3.5 Validating clusters: Maltreatment and negative emotionality
Clusters were further validated by comparing them via a t test and multivariate analysis of variance on theoretically relevant dimensions not used to derive them and found in prior empirical research to distinguish psychopathy subtypes. The secondary subtype (cluster 1) reported significantly more internalizing problems, t(98) = 2.04, p < .05 compared to the primary subtype. And although the secondary subtype had suffered more abuse of all kind, compared to the primary subtype and the comparison group (see Table 4), the multivariate analysis of variance did not reach significance probably due to an underreporting of maltreatment. On all scales the average report of abuse was well below three (see Table 5), an indication of possible underreporting of maltreatment considering the classification per scale. Comparison youths had slightly more internalizing problems and reported more abuse of all types than primary variants, but less than secondary variants.
Table 4
Comparisons between the primary and secondary subtype and the nonpsychotic comparison group
Comparison group Primary subtype Secondary subtype
(n = 126) (n = 67) (n = 33) BPMY Internalizing (SD) 1.66 (2.3) 1.37 (1.88) 2.21 (2.03) JTV Emotional abuse (SD) 1.52 (.87) 1.40 (.70) 1.65 (.82) JTV Physical abuse (SD) 1.42 (.79) 1.37 (.72) 1.71 (.96) JTV Sexual abuse (SD) 1.15 (.49) 1.18 (.67) 1.21 (.80) JTV Emotional neglect (SD) 1.96. (1.02) 1.75 (.89) 1.92 (.95) JTV Physical neglect 1.43 (.68) 1.42 (.61) 1.56 (.71)
Table 5
Childhood Trauma classification per scale Emotional
Abuse Physical Abuse Sexual Abuse Emotional Neglect Physical Neglect
None (or minimal) 5-8 5-7 5 5-9 5-7 Low (to average) 9-12 8-9 6-7 10-14 8-9 Average (to critical) 13-15 10-12 8-12 15-17 10-12 Critical (to extreme) ≥ 16 ≥ 13 ≥ 13 ≥ 18 ≥ 13
3.6 Validating clusters: Substance use and processing of substance-related stimuli: attentional
bias
The two psychopathy clusters and comparison youth were compared on their substance use and processing of substance-related stimuli (attentional bias). The results of one-way analyses of variance revealed a significant difference between groups in substance use, F(2, 266) = 3.51, p < .05. Given a priori hypotheses, planned comparisons between the different (sub)groups were conducted. The analyses revealed that primary and secondary subgroups did not differ significantly from each other, but the primary subgroup differed from the comparison group, t(226) = 2.45, p < .25 (Bonferroni correction).
Figure 2
The three groups did not differ significantly on attentional bias. Secondary variants, however, displayed on average more attentional bias to substance-related stimuli (see figure 3).
Figure 3
4. Discussion
Results of this study are consistent with past research indicating that the construct of psychopathy is heterogeneous and that high-anxious secondary subtypes of psychopathic youth endorse more negative emotionality than low-anxious primary subtypes. The intended contribution of this study, however, was demonstrating that the subtypes of juvenile psychopathy, which were identified via cluster analysis, differed in their substance use and processing of substance-related stimuli. A difference in substance use between groups was found, although contrary to expectations not between the primary and the secondary subtypes, but between the primary subtype and the comparison group. As for attentional bias no differences between groups were found.
On average the primary subtype displayed more substance use than the secondary subtype and comparison group. This finding once more confirms the possibility that etiological correlates of substance (ab)use differ in subgroups of psychopathic individuals and nonpsychopathic individuals. However, in this sample of juvenile offenders anxiety sensitivity is not a specific strong motive for substance (ab)use. Individuals high on anxiety, with or without elevated psychopathic traits, are not especially sensitive for the anxiolytic and addictive effects of substances like cannabis or alcohol.
Speculative hypotheses, therefore, that could be addressed in future studies are that the lack of anxiety sensitivity and that temperamental differences (e.g., fearlessness or risk taking) might be more current concerns to start using substances of abuse for the primary subgroup. High-anxious secondary variants on the other hand are perhaps more easily overwhelmed in negatively charged or risky situations and are likely to withdrawn from those situations and therefore are not drawn easily to using substances of abuse. It is furthermore remarkable that neither subgroup processed substance-related stimuli significantly differently from each other nor from nonpsychotic youths. One possible explanation for this is that attentional bias is not only elicited by prior frequent experiences with substance use, as is
suggested by the incentive sensitization theory, but also by dispositional characteristics and contextual experiences across youths who enter the juvenile justice system. On average the secondary subtype was still more attentively engaged by substance-related stimuli than was the primary subgroup or the comparison group. Therefore, anxiety sensitivity might not be a current concern to start using substances, but it might be associated with hypervigilance toward substance-related stimuli. However, current findings do not account for how processes of AB and anxiety sensitivity are interrelated or how they might be seen as cognitive and emotional outputs of the sensitized dopaminergic system. Both seem to motivate substance-seeking behaviour.
Also importantly, finding are only partially consistent with past research suggesting that the two subgroups are not completely distinguished in their levels of ‘core’ psychopathic traits (the interpersonal and affective dimensions). The core psychopathic traits have been increasingly used to designate an important subgroup of antisocial youths (Skeem et al., 2003). However, current findings suggest that a further differentiation is needed as primary variants display more affective problems, but not more interpersonal problems compared to secondary variants. Thus, causal theories of the core psychopathic traits need to account for this heterogeneity.
The results of this study must be considered within the context of several limitations. First, whereas current findings and prior research found that anxiety might be associated with hypervigilance toward substance-related stimuli (Maygar et al., 2011), this study ruled out the possibility that differences between psychopathy subgroups in the processing of substance-related stimuli were entirely accounted for by differences in anxiety, as these two variables were not significantly correlated. Second the current study is limited to male juvenile offenders and findings may not generalize to girls or community samples. This study employed an adolescent offender sample housed in secure and residential facilities. The average YPI-S scores were fairly high in the whole sample and it should, therefore, be recognized that present study could not establish an actual comparison of true psychopathic and non-psychopathic individuals. Thirdly, the reliance on self-report measures in the measurement of mental and physical abuse, and perhaps likewise substance use, may have resulted in the minimization of symptoms/substance use. Especially if secondary psychopathic variants were motivated to deny past abuse and substance use out of fear for loss of reputation or repercussions. Hence, it would be more informative to conduct replications in secured facilities in which non-self report indicators of substance abuse severity are used. Finally, this cross-sectional study cannot conclusively address etiological issues as the lack of temporal ordering necessary to help reveal causal relationships is evident. That is, substance abuse and attentional bias may reflect temperamental or trait differences or may result from exposure to negative or impoverished home situations and neighbourhood environments that cause an inclination to using substances of abuse. These other negative experiences can more strongly impact substance abuse, offending behaviour and the different manifestations of antisocial behaviour in juveniles.
Despite these limitations, the current study forms a first systematic attempt to address the role of anxiety sensitivity on substance abuse of antisocial adolescents with elevated psychopathic trait. In terms of policy and its application, the juvenile forensic psychiatry should recognize that juvenile offenders subgroups do not only show heterogeneity between groups but also within subgroups. Applying uniform treatment models across the range of adolescent offenders may prove less effective than tailoring risk assessment and treatment to specific subpopulations of antisocial youth. It is possible that to achieve offense reduction and improve mental health greater gains may be made if treatment is targeted to the psychopathic subgroups identified in this study. This is increasingly important for treatment-resistant individuals who require more specialized intervention, like psychopathic individuals. The careful assessment of criminogenic needs and responsivity factors acknowledges the principle that good offender assessment is more than making decisions on the level
of risk and equally recognizes the fundamental potential of the human condition to change. It therefore forms the main road to effective offender treatment by having the potential to identify appropriate changeable treatment targets linked to offending. Psychopathy is often regarded as a bundle of features that strongly moderate responsivity (Hare & Neumann, 2009). Looking at it this way, there is a risk that psychopathy is too easily assumed recalcitrant and unalterable, instead of being psychologically challenged and in need of special services. Present findings can shape hypotheses about targeted interventions for subgroups of psychopathic juvenile offenders. For example, cognitive-behavioural interventions may be most effective at treating internalizing problems (e.g., anxiety) that distinguish secondary variants (Chaffin & Friedrich, 2004). The low-anxious subtype on the other hand might benefit more from interventions that teaches parents methods of using positive reinforcement to encourage prosocial behaviour (Hawes & Dadds, 2005). Consequently, by using interweaving pathways of potentially relevant processes, like negative life experiences, brain development and cognition (see Buckholtz et al. (2010) for a neurochemical and neurophysiological perspective), an explicitly developmental perspective in research should detect favourable responsivity or protective factors that might help to better tailor treatment based on the strengths and weaknesses in the personality profiles of psychopathic individuals.
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