Evelien Platje

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.

Long-term stability of the cortisol awakening response over adolescence

The cortisol awakening response (CAR) has been widely assessed as a measure of hypothalamic-pituitary-adrenal (HPA) axis activity. Short-term stability is high; however, little is known about the long-term stability of the CAR. Because there are indications that development in adolescence influences HPA axis activity, this study investigated the stability of the CAR over adolescence. Participants were 229 boys and 181 girls from an adolescent general population sample who were assessed in three consecutive years, at mean ages of 15.0 (SD=0.4), 16.0 (SD=0.4) and 17.0 (SD=0.4) years. Cortisol was analyzed in saliva sampled at awakening, and 30 and 60min later. Stability was investigated both as rank-order and as mean-level stability. Effects of physical development during adolescence on stability were investigated as well. Rank-order stability was moderate to low, with tracking coefficients (interpretable as stability coefficients over time) of .15 (p<.001) for cortisol at awakening and .24 (p<.001) for cortisol 30 and 60min after awakening. Mean-levels of cortisol at awakening did not change, while the response to awakening increased over the years (linear slopes for cortisol 30 and 60min after awakening all p<.01). The increase may reflect the physical development of the adolescents. This is the first study, in a large population based sample, indicating that the rank-order of the CAR is stable over the course of several years. Interestingly, mean-levels of the cortisol response to awakening increased over the years, suggesting a maturation of HPA axis reactivity in relation to physical development over adolescence. Physical development should therefore be taken into account when investigating the CAR as a measure of HPA axis activity in adolescence.

Testosterone and cortisol in relation to aggression in a non‐clinical sample of boys and girls

Testosterone and cortisol have been proposed to jointly regulate aggressive behavior. However, few empirical studies actually investigated this joint relation in humans, and reported inconsistent findings. Also, samples in these studies were small and/or specific, and consisted largely of males. Therefore, in the current study testosterone and cortisol in relation to aggression were investigated in a non-clinical sample of 259 boys and girls (mean age 16.98 years, SD = 0.42, 56% boys). A positive testosterone/cortisol ratio, that is, high testosterone relative to cortisol, was found to be associated with aggressive behavior, explaining 7% of the variance. The interaction between testosterone and cortisol was not related to aggressive behavior and gender differences were not found. The ratio may reflect an imbalance leaving the individual more prone to rewarding aspects, than fearful of negative implications of aggressive behavior. Current findings indicate that this relation can be generalized to aggression in non-clinical adolescents.

Executive Functioning, Reward/Punishment Sensitivity, and Conduct Problems in Boys With Callous-Unemotional Traits:

Callous-unemotional (CU) traits are thought to characterize children exhibiting persistent and severe conduct problems (CPs). Reward and punishment sensitivity have often been investigated, yet executive function problems have mostly been studied in adults. Moreover, the level of co-occurring CPs is important to take into account. Therefore, the current study investigated differences in reward responsivity, punishment sensitivity, and executive functioning (EF) between four subgroups of general community boys (N = 346, Mage = 14.01 years, SD = 1.19): high CU/high CP, low CU/high CP, high CU/low CP, and low CU/low CP. Boys with high CU/high CP showed significantly more EF problems, but similar reward and punishment sensitivity as low CU/high CP boys. Boys with high CU/low CP did not differ from low CU/low CP boys. Severity of executive function problems appears to distinguish boys who show a combination of CU-traits and CPs from boys with CPs alone.

Adolescent Antisocial Behavior Explained by Combining Stress-Related Parameters

Many stress-related parameters have been associated with antisocial behavior, including low cortisol awakening responses (CAR), as well as low cortisol and alpha-amylase reactivity to stress. These parameters reflect different, yet interrelated components of the stress system, yet it remains to be determined whether they exert joint or independent effects. Therefore, this study examined them in concert, as this may offer a better explanation of the psychophysiological mechanism’s underlying antisocial behavior. Antisocial behavior was assessed through self-report by 197 general population boys and girls (Mage = 17.31, SD = 0.44). The CAR was assessed, as well as cortisol and alpha-amylase reactivity to a public speaking task. Neither stress-related parameter was independently related to antisocial behavior. The best explanation was provided by a CAR × Cortisol reactivity interaction, indicating that in youth with a low CAR, antisocial behavior was positively associated with cortisol reactivity. In youth with a high CAR, no association between antisocial behavior and cortisol reactivity was found. Between cortisol and alpha-amylase reactivity a trend toward an interaction appeared, indicating a negative association between cortisol reactivity and antisocial behavior in those with low alpha-amylase reactivity, and a positive association in those with high alpha-amylase reactivity. These findings indicate that in order to understand the mechanisms underlying antisocial behavior, the stress system should be studied comprehensively rather than focus on single parameters. Particularly cortisol parameters appear to be jointly related to antisocial behavior, the additional value of alpha-amylase reactivity to cortisol reactivity may however be limited.

Corrigendum to A longitudinal biosocial study of cortisol and peer influence on the development of adolescent antisocial behavior [Psychoneuroendocrinology, 38(11), (2013), 2770-2779]

VU University Medical Center, Department of Child and Adolescent Psychiatry, Amsterdam, The Netherlands Curium, Leiden University Medical Center, Leiden, The Netherlands Departments of Criminology, Psychiatry, and Psychology, Jerry Lee Center of Criminology, University of Pennsylvania, Philadelphia, USA Utrecht University, Research Center Adolescent Development, Utrecht, The Netherlands VU University, Department of Developmental Psychology, Amsterdam, The Netherlands Tilburg University, Tilburg School of Behavioral and Social Sciences, Tilburg, The Netherlands

Neurobiological correlates of disruptive behaviour disorder in a normal population: Differences between boys and girls

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