Arne Popma

Cortisol moderates the relationship between testosterone and aggression in delinquent male adolescents

BACKGROUND In animals, strong evidence exists for an association between testosterone and aggression. In humans, and particularly in children and adolescents, findings have been less consistent. Previous research has suggested that this may partly be due to moderating effects of other factors, e.g., hormones. This study aims to investigate the moderating effect of cortisol on the relationship between testosterone and subtypes of aggression in delinquent male adolescents. METHODS Participants were 103 boys (mean age 13.7) referred to a delinquency diversion program. Testosterone and cortisol levels were determined from saliva samples collected during resting conditions and related to self-report scores on overt and covert aggression. RESULTS Linear regression analyses revealed a significant interaction between cortisol and testosterone in relation to overt aggression, with a significant positive relationship between testosterone and overt aggression in subjects with low cortisol levels but not in subjects with high cortisol levels. Using the same model for covert aggression, no significant effects of testosterone, cortisol, or testosterone x cortisol interaction were found. CONCLUSIONS These results indicate a moderating effect of cortisol on the relationship between testosterone and overt aggression in delinquent male adolescents. Implications and directions for future research are discussed.

Hypothalamus pituitary adrenal axis and autonomic activity during stress in delinquent male adolescents and controls

OBJECTIVE Patterns of low autonomic arousal have consistently been related to delinquency and disruptive behavior disorders (DBD) in children and adolescents. Findings on another stress regulating mechanism, the hypothalamic pituitary adrenal (HPA) axis, have been inconsistent, which may partly be due to not considering specific stress reactivity measures. Therefore, the aim of the present study was to investigate the relationship between disruptive behavior in male adolescents and their HPA and autonomic reactivity to a standard public speaking task (PST). METHOD Responsivity to the PST of cortisol, heart rate (HR), skin conductance level (SCL) and self-reported negative feelings was measured, and compared between 12and14-year-old boys who attended a delinquency diversion program (DP), with and without DBD (DP+, n=22 and DP-, n=49, resectively), and matched normal controls (NC, n=30). DBD diagnoses were based on a structured psychiatric interview. RESULTS The DP+ group, but not the DP- group, showed a significantly decreased cortisol and HR response during the PST as compared with the NC group. No significant effects were found for SCL. All subjects connoted the task negatively. CONCLUSIONS The results indicate that low cortisol and HR responsivity to stress may be a neurobiological marker for delinquent boys with DBD, but not for those without DBD. Directions for future research and clinical implications are discussed.

The Diurnal Cortisol Cycle in Delinquent Male Adolescents and Normal Controls

Patterns of low hypothalamus–pituitary–adrenal (HPA) activity have been observed in antisocial groups. As conflicting results have been reported in children and adolescents, the aim of this study was to further investigate HPA activity in antisocial behavior by studying the relationship between the diurnal cortisol cycle, as well as the cortisol awakening response (CAR), and antisocial behavior in male adolescents. The diurnal cortisol cycle and the CAR during the first hour after awakening were compared between 12- to 14-year-old boys who attended a delinquency diversion program (DP), with and without a disruptive behavior disorder (DBD) (respectively DP+; n=24 and DP−; n=65), and matched normal controls (NC; n=32). The DP+ group, but not the DP− group, showed a significantly slower decrease of cortisol during the diurnal cycle than the NC group. Furthermore, the DP+ group had significantly lower cortisol levels in the first hour after awakening as compared with the NC group. The results indicate altered HPA activity in delinquent boys with a DBD. Etiological mechanisms, directions for future research, and clinical implications are discussed.

Validation of the Dutch Reactive Proactive Questionnaire (RPQ): Differential Correlates of Reactive and Proactive Aggression From Childhood to Adulthood

This study reports reliability and validity of the Dutch Reactive-Proactive Aggression Questionnaire (RPQ). In total, 845 participants completed the RPQ along with other measures of aggression. Groups consisted of non-offender participants, criminal offenders, youngsters (age 6-18), and adults (age above 18). Test-retest stability in a subsample of 324 childhood arrestees was good (all ICCs > 0.41). A confirmatory factor analysis supported the same two-factor structure as in the original RPQ. Convergent validity was adequate (all rs > 0.16). Moreover, results demonstrated that the proactive and reactive subscales were differentially related to measurements of callousness and impulsiveness, respectively. Criterion validity was shown in that non-offender subjects demonstrated significantly lower RPQ scores than offender samples. Finally, construct validity was demonstrated in that violent offenders showed higher aggression scores than non-violent offenders. Proactive aggression showed different developmental trajectories within non-offender versus criminal samples, indicating that this form of aggression may be more pathological.

Longitudinal associations in adolescence between cortisol and persistent aggressive or rule-breaking behavior

Although several studies have associated antisocial behavior with decreased cortisol awakening responses (CAR), studies in adolescent samples yielded inconsistent results. In adolescence however, the CAR develops and antisocial behavior is heterogeneous in type and persistence. Therefore this longitudinal study compared persistent aggressive and rule-breaking adolescents to low aggressive and rule-breaking adolescents on the development of the CAR from ages 15 to 17 (N=390). Persistently high aggressive adolescents showed decreased cortisol levels at awakening consistently over the years (Δχ(2)(1)=6.655, p=.01) as compared to low aggressive adolescents. No differences between adolescents showing persistent high rule-breaking and low rule-breaking were found. This longitudinal study is the first to show that persistent aggression, but not rule-breaking behavior, is related to neurobiological alterations. Moreover, despite development of the CAR over adolescence, the decrease in cortisol is consistent over time in persistent high aggressive adolescents, which is an important prerequisite for the prediction of persistent aggression.

The predictive value of low heart rate and heart rate variability during stress for reoffending in delinquent male adolescents

Low autonomic (re)activity is a consistent correlate of antisocial behavior in juveniles. However, longitudinal research relating autonomic measures to persistent antisocial behavior has remained scarce. Therefore, in the present study we examined the predictive value of heart rate (HR) and heart rate variability (HRV, often studied as respiratory sinus arrhythmia) for reoffending in delinquent male adolescents. At initial assessment, HR and HRV were measured at rest and in response to a public speaking task. Registered reoffending was assessed after 5-year follow-up. Attenuated HR response and stronger HRV response to stress predicted higher reoffending rates. Results provide evidence that HR/HRV reactivity are neurobiological markers for persistent juvenile antisocial behavior. Although effect sizes were small to moderate, our findings underscore the consistency of the relationship between autonomic markers and antisocial behavior.

Fear conditioning, persistence of disruptive behavior and psychopathic traits: an fMRI study

Children diagnosed with Disruptive Behavior Disorders (DBD), especially those with psychopathic traits, are at risk of developing persistent and severe antisocial behavior. Deficient fear conditioning may be a key mechanism underlying persistence, and has been associated with altered regional brain function in adult antisocial populations. In this study, we investigated the associations between the neural correlates of fear conditioning, persistence of childhood-onset DBD during adolescence and psychopathic traits. From a cohort of children arrested before the age of 12 years, participants who were diagnosed with Oppositional Defiant Disorder or Conduct Disorder in previous waves (mean age of onset 6.5 years, s.d. 3.2) were reassessed at mean age 17.6 years (s.d. 1.4) and categorized as persistent (n=25) or desistent (n=25) DBD. Using the Youth Psychopathic Traits Inventory and functional magnetic resonance imaging during a fear conditioning task, these subgroups were compared with 26 matched healthy controls from the same cohort. Both persistent and desistent DBD subgroups were found to show higher activation in fear processing-related brain areas during fear conditioning compared with healthy controls. In addition, regression analyses revealed that impulsive-irresponsible and grandiose-manipulative psychopathic traits were associated with higher activation, whereas callous-unemotional psychopathic traits were related to lower activation in fear-related areas. Finally, the association between neural activation and DBD subgroup membership was mediated by impulsive-irresponsible psychopathic traits. These results provide evidence for heterogeneity in the neurobiological mechanisms underlying psychopathic traits and antisocial behavior and, as such, underscore the need to develop personalized interventions.

Incentive Processing in Persistent Disruptive Behavior and Psychopathic Traits: A Functional Magnetic Resonance Imaging Study in Adolescents.

BACKGROUND Children with early-onset disruptive behavior disorder (DBD), especially those with callous-unemotional traits, are at risk of developing persistent and severe adult antisocial behavior. One possible underlying mechanism for persistence is deficient reward and loss sensitivity, i.e., deficient incentive processing. However, little is known about the relation between deficient incentive processing and persistence of antisocial behavior into adulthood or its relation with callous-unemotional and other psychopathic traits. In this study, we investigate the relationship between the neural correlates of incentive processing and both DBD persistence and psychopathic traits. METHODS In a sample of 128 adolescents (mean age 17.7) with a history of criminal offending before age 12, functional magnetic resonance imaging was performed during a monetary incentive delay task designed to assess neural responses during incentive processing. Neural activation during incentive processing was then associated with DBD persistence and psychopathic traits, measured with the Youth Psychopathic Traits Inventory. RESULTS Compared with both healthy control subjects and youths who had desisted from DBD, persistent DBD subjects showed lower neural responses in the ventral striatum during reward outcomes and higher neural responses in the amygdala during loss outcomes. Callous-unemotional traits were related to lower neural responses in the amygdala during reward outcomes, while other psychopathic traits were not related to incentive processing. CONCLUSIONS In the current study, aberrant incentive processing is related to persistence of childhood antisocial behavior into late adolescence and to callous-unemotional traits. This mechanism may underlie treatment resistance in a subgroup of antisocial youth and provide a target for intervention.

Differential Relations Between Juvenile Psychopathic Traits and Resting State Network Connectivity

Traditionally, neurobiological research on psychopathy has focused on categorical differences in adults. However, there is evidence that psychopathy is best described by a set of relatively independent personality dimensions, that is, callous‐unemotional, grandiose‐manipulative, and impulsive‐irresponsible traits, which can be reliably detected in juveniles, allowing investigation of the neural mechanisms leading to psychopathy. Furthermore, complex psychiatric disorders like psychopathy are increasingly being conceptualized as disorders of brain networks. The intrinsic organization of the brain in such networks is reflected by coherent fluctuations in resting state networks (RSNs), but these have not been studied in sufficient detail in relation to juvenile psychopathic traits yet. The current study investigated the distinct associations of juvenile psychopathic traits dimensions with RSN connectivity. Resting‐state functional MRI and independent component analysis were used to assess RSN connectivity in a large sample of adolescents (n = 130, mean age 17.8 years) from a childhood arrestee cohort. Associations between scores on each of the three psychopathic traits dimensions and connectivity within and between relevant RSNs were investigated. Callous‐unemotional traits were related to aberrant connectivity patterns of the default mode network, which has been implicated in self‐referential and moral processes. Impulsive‐irresponsible traits were associated with altered connectivity patterns in the frontoparietal cognitive control networks. Grandiose‐manipulative traits were not associated with altered connectivity patterns. These findings confirm the association between psychopathic traits and brain network connectivity, and considerably add to emerging evidence supporting neurobiological heterogeneity in the processes leading to psychopathy. Hum Brain Mapp 36:2396–2405, 2015.

Neurocognitive effects of neurofeedback in adolescents with ADHD: a randomized controlled trial.

OBJECTIVE Neurofeedback aims to reduce symptoms of attention-deficit/hyperactivity disorder (ADHD), mainly attention problems. However, the additional influence of neurofeedback over treatment as usual (TAU) on neurocognitive functioning for adolescents with ADHD remains unclear. METHOD By using a multicenter parallel randomized controlled trial (RCT) design, male adolescents with a DSM-IV-TR diagnosis of ADHD (mean age = 16.1 years; range, 12-24) were randomized to receive either a combination of TAU and neurofeedback (n = 45) or TAU (n = 26). Randomization was computer generated and stratified by age group (ages 12 through 15, 16 through 20, and 21 through 24 years). The neurofeedback intervention consisted of approximately 37 sessions over a period of 25 weeks of theta/sensorimotor rhythm training on the vertex (Cz). Primary neurocognitive outcomes included performance parameters derived from the D2 Test of Attention, the Digit Span backward, the Stroop Color-Word Test and the Tower of London, all assessed preintervention and postintervention. Data were collected between December 2009 and July 2012. RESULTS At postintervention, outcomes of attention and/or motor speed were improved, with faster processing times for both intervention conditions and with medium to large effect sizes (range, ηp2 = .08-.54; P values < .023). In both groups, no improvements for higher executive functions were observed. Results might partly resemble practice effects. CONCLUSIONS Although neurocognitive outcomes improved in all adolescents receiving treatment for ADHD, no additional value for neurofeedback over TAU was observed. Hence, this study does not provide evidence for using theta/sensorimotor rhythm neurofeedback to enhance neurocognitive performance as additional intervention to TAU for adolescents with ADHD symptoms. TRIAL REGISTRATION Trialregister.nl identifier: 1759.