Types of Behavior Associated with Poor Outcomes

Early research attempting to identify early indicators of risk for persistent antisocial behavior focused on the frequency and severity of the behavior displayed, with severity being defined as the number and variety of different behaviors displayed by the child and the number of settings in which the child displays the behaviors. For example, Robins reported on a classic longitudinal study of 314 children referred to a child mental health clinic for CD symptoms and reported that the risk for showing an antisocial disorder as an adult was a linear function of the number of symptoms exhibited in childhood. Specifically, 15% of children with 3 to 5 symptoms in childhood were diagnosed with an antisocial disorder as an adult, in comparison to 25% of children with 6 or 7 symptoms, 29% of children with 8 or 9 symptoms, and 43% of children with greater than 10 symptoms.

Another early marker of severity for children and adolescents with CD has been the presence of aggression. That is, when antisocial behavior is separated into those behaviors that can be considered aggressive (eg, bullies others, initiates physical fights) and those that are nonaggressive (eg, vandalism, lies, truant), the aggressive behaviors seem to be more stable and stronger predictors of problems continuing into adulthood. In addition to simply documenting the presence of aggression, there has been research suggesting that the form that the aggression takes could be important. For example, research has distinguished between reactive aggression, which occurs as an angry response to provocation or threat, and proactive aggression, which is typically unprovoked and often used for instrumental gain or dominance over others. Research suggests that some children with severe conduct problems only show reactive forms of aggression, whereas others show a combination of both reactive and proactive forms of aggression. Children showing combined forms of aggression often have more problems across development.

Thus, research suggests that the number, severity, and degree of harm that a child’s antisocial behavior causes to others are important factors to consider as markers of risk for poor outcome. To reflect this, the diagnostic criteria for CD in the most recent editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) have required that the person must show at least 3 different antisocial behaviors over the past 12 months to be diagnosed with CD, and then the severity is coded as:

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  Mild: with few symptoms beyond the diagnostic threshold and behavior that causes relative minor harm to others (eg, lying, truancy);

  
  
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  Moderate: the number of symptoms and amount of harm to others is intermediate to those specified as “mild” or “severe”;

  
  
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  Severe: many symptoms beyond the diagnostic threshold that cause considerable harm to others (eg, rape, use of a weapon).

Childhood Onset Conduct Disorder

Another important variation in how antisocial behavior is expressed in children is the age at which the serious antisocial behavior is first displayed. Persons who begin showing behavior problems before adolescence are much more likely to continue to show problems into adulthood compared with those whose problems onset during adolescence. For example, in a birth cohort from New Zealand that was followed into adulthood, the rate of official convictions for violent acts in adulthood (before age 32) was as follows:

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  32.7% for males who began showing serious conduct problems before adolescence

  
  
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  10.2% for males who began showing serious conduct problems in adolescence

  
  
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  .4% for males who did not show serious conduct problems in either childhood or adolescence.

Even before adolescence, there is some indication that the younger the child begins to show serious conduct problems, the more severe and persistent his or her antisocial behavior is likely to be. Importantly, the age of onset of antisocial behavior may subsume some of the other behavioral patterns that predict poor outcomes. That is, age of onset is negatively associated with number of conduct problems and with the level of aggression displayed by the child.

As a result of this research, the most recent editions of the DSM have also included criteria to distinguish early and late onset patterns of CD:

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  Childhood-onset type : Individuals show at least one symptom characteristic of CD before age 10 years.

  
  
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  Adolescent-onset type : Individuals show no symptom characteristic of CD before age 10 years.

The different outcomes for these 2 subgroups of antisocial individuals may be due to differences in the causal processes that lead to the different trajectories. Specifically, the childhood-onset pattern seems to be more strongly related to neuropsychological (eg, deficits in executive functioning) and cognitive (eg, low intelligence) deficits. Also, children who show the childhood-onset pattern seem to show more temperamental and personality risk factors, such as impulsivity, attention deficits, and problems in emotional regulation. As a result, this group often displays attention-deficit hyperactivity disorder (ADHD), and it is possible that the presence of ADHD contributes to their poor outcomes. Importantly for early identification, the impulsivity and hyperactivity symptoms of ADHD often emerge before the child’s conduct problems and can be the first indicator that the child is having problems regulating their behavior and emotions.

In contrast to this early-onset trajectory, persons whose antisocial behavior onsets in adolescence typically do not show the same number and severity of dispositional risk factors, like ADHD. However, they are often described as showing higher levels of rebelliousness and being more rejecting of conventional values and status hierarchies. As a result, youths in the adolescent-onset pathway are often considered as showing an exaggeration of the normative process of adolescent rebellion in which the adolescent engages in antisocial and delinquent behaviors as a misguided attempt to obtain a subjective sense of maturity and adult status in a way that is maladaptive (eg, breaking societal norms) but encouraged by an antisocial peer group.

Differences Between Conduct Disorder with and Without Elevated Callous-UnemotionalTraits

In terms of clinical importance, antisocial youth with CU traits (relative to other antisocial youth) show the following:

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  A more stable pattern of antisocial behavior that predicts a greater likelihood of the antisocial behavior continuing into adulthood

  
  
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  More severe aggression that results in greater harm to others

  
  
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  Aggression that is more likely to be premeditated and instrumental (ie, for personal gain and dominance)

  
  
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  Poorer response to many of the typical health interventions used to treat CD.

Thus, the presence of elevated CU traits identifies a group of antisocial youth who are important for early intervention and treatment.

In addition, there is evidence that these traits also classify a group of youth with CD who show very different genetic, cognitive, emotional, and social characteristics from other antisocial youth. Specifically, antisocial youth with elevated CU traits (relative to other antisocial children and adolescents):

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  Show stronger genetic influences on their conduct problem behavior

  
  
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  Show an insensitivity to punishment cues under many conditions

  
  
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  View aggression as a more acceptable means for obtaining goals and place greater importance on dominance and revenge in social conflicts

  
  
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  Display reduced emotional responses to cues of distress in others

  
  
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  Show impairments in their selective attention to caregivers face in the first year of life, make less eye contact with caregivers in childhood, and attend less to the eye region in others later in life

  
  
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  Show conduct problems that are less related to hostile and coercive parenting but are more strongly related to warm parenting

  
  
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  Are more likely to associate with deviant peers, are more likely to commit crimes with peers, and are more influential in encouraging antisocial behavior in their peers.

This extensive list of differences between antisocial youth with and without elevated CU traits has led to several theories proposing different causes to the antisocial behavior in the 2 groups. For example, children with serious conduct problems and elevated CU traits have a temperament that could make them more difficult to socialize (eg, less sensitive punishment) and miss early signs of distress in others (eg, reduced emotional responses to others’ distress). These processes can interfere with the normal development of key aspects of conscience (ie, empathy and guilt) and place the child at risk for a particularly severe and aggressive pattern of antisocial behavior.

In contrast, children with childhood-onset antisocial behavior with normative levels

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  Are highly reactive to emotional cues in others

  
  
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  Are highly distressed by the effects of their behavior on others

  
  
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  Display higher levels of emotional reactivity to provocation from others.

They show conduct problems that are

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  Less strongly influenced by genetic factors

  
  
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  More strongly associated with hostile/coercive parenting.

Based on these findings, it appears that children in this group show a temperament characterized by strong emotional reactivity combined with inadequate socializing experiences that lead to failure in the development of the skills needed to adequately regulate their emotional reactivity. The resulting problems in emotional regulation can result in the child committing impulsive and unplanned aggressive and antisocial acts, for which he or she may feel remorseful afterward, but for which he or she may still have difficulty controlling in the future.

Implications for Research

From this brief review of research, it is clear that the distinction between antisocial youth with and without elevated CU traits may encompass several of the previous attempts to define important subgroups of children at risk for particularly severe and stable patterns of antisocial behavior. Specifically, children with elevated CU traits and conduct problems tend to show a greater number of conduct problems, more aggressive behavior, and more instrumental aggression. Furthermore, CU traits seem to designate a subgroup of children within those with both ADHD and early conduct problems who show distinct emotional and cognitive characteristics and who are at particularly high risk for later antisocial behavior. With respect to the latter, McMahon and colleagues reported that CU traits assessed in seventh grade significantly predicted adult antisocial outcomes (eg, adult arrests, adult antisocial personality symptoms) even after controlling for ADHD, oppositional defiant disorder, CD, and childhood-onset of CD.

The presence of elevated CU traits seems particularly important for guiding research investigating the causes of antisocial behavior because they differentiate groups with very different emotional and cognitive characteristics. To illustrate this, Viding and colleagues reported that amygdala responses to fearful faces (relative to calm faces) were stronger in boys (ages 10–16) with conduct problems without elevated CU traits but were weaker in boys with conduct problems who were elevated on CU traits compared with controls. Thus, ignoring the differences among the 2 groups high on conduct problems would have hidden the differences with controls and led to erroneous conclusions on the potential importance of emotional responding for understanding the development of conduct problems.

Another way that research on CU traits could be critical for causal theories of antisocial behavior is that it promotes an integration of research on processes in typically developing children with research on how these developmental processes can go awry and lead to problem behavior. As noted above, many theories to explain the differences between antisocial youth with and without elevated CU traits include processes that have long been the focus of developmental research, such as how children develop guilt, empathy, and other prosocial emotions and how children develop the skills necessary to regulate their emotions. Thus, causal theories for antisocial behavior can be advanced by integrating it with the vast research on conscience development and the development of emotional regulation in non-antisocial children.

Furthermore, this approach to research on antisocial behavior in children and adolescents would be consistent with the research domain criteria (R-DoC) framework that is being advanced by the National Institute of Mental Health. Specifically, the R-DoC initiative was implemented to overcome some of the limitations in behaviorally based approaches to classifying mental health disorders, such as the great heterogeneity in the neurocognitive mechanisms that can lead to a single behavioral diagnosis like CD. As noted above, the use of CU traits seems to reduce this heterogeneity by designating groups with similar behavioral manifestations (ie, CD) but with unique profiles of neurocognitive processes. Furthermore, these neurocognitive profiles can be explained using the R-DoC domains, with the group without elevated CU traits showing problems in the regulation of the negative emotional valence system responsible for responses to aversive situations and contexts (eg, anxiety, frustration, and loss) and the group with elevated CU traits showing problems primarily in the systems for social processing that mediate responses to interpersonal settings, especially related to affiliation and attachment. Thus, advances in knowledge of the RDoC domains could be critical for guiding research on how these domains may be related to the development of antisocial behavior.

Implications for Prevention and Treatment

The research on CU traits and the different developmental pathways to antisocial behavior could also have many important implications for preventing and treating CD. Existing research on effective treatments for antisocial behavior in children and adolescents highlights the need to

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  Intervene as early in development as possible

  
  
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  Intervene with comprehensive treatments that target many dispositional and contextual risk factors that can lead to or maintain the child’s antisocial behavior

  
  
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  Tailor interventions to the unique needs of children and adolescents with serious antisocial behavior, because the most important targets of intervention may vary across antisocial individuals.

Research on the differences between antisocial children and adolescents with and without elevated CU traits can advance each of these goals.

For example, as noted above, the most effective treatments for antisocial behavior intervene early in development when the child’s conduct problems are less severe. The research on the different developmental mechanisms leading to CD could allow interventions to target children who show temperamental vulnerabilities (eg, children who miss early cues to others’ distress or who have problems regulating their emotions) even before the serious conduct problems develop. Furthermore, parenting interventions could be modified to meet the unique needs of these children with very different temperaments.

This ability to tailor treatments to the needs of the different youth with CD could be the most important benefit of recognizing the various developmental pathways to antisocial behavior. That is, the different characteristics associated with antisocial behavior in those with and without elevated CU traits could help in determining the most effective combination of services for an individual child or adolescent. As noted previously, children and adolescents who show significant levels of CU traits present quite a treatment challenge. However, despite their poor response to many traditional treatments, their antisocial behavior can be reduced when intensive treatments are tailored to their unique cognitive and emotional characteristics.

For example, Hawes and Dadds reported that clinic-referred boys (ages 4–9) with conduct problems and elevated CU traits showed reductions in their conduct problems during the phase of a parenting intervention that focused on use of positive reinforcement to encourage prosocial behavior. This outcome would be consistent with the reward-oriented response style that appears to be characteristic of children with CU traits. Similarly, Caldwell and colleagues demonstrated that adolescent offenders with CU traits improved (ie, showed significant reductions in reoffending) when treated using an intensive treatment program that used reward-oriented approaches, targeted the self-interests of the adolescent, and taught empathy skills. Finally, White and colleagues tested the effectiveness of an intervention for adolescents in the juvenile justice system that focused on engaging the child and family in treatment and providing motivations for change that are individualized for each family and child. Results indicated that CU traits were associated with improvements in behavior over the course of treatment and with decreases in risk for reoffending at 6- and 12-month follow-ups. Thus, certain treatments can reduce the level and severity of the antisocial behavior of youths with CU traits, if they are tailored to the unique characteristics of this group.