Neuroendocrine and neurotransmitter correlates in children with antisocial behavior

Increased ghrelin and decreased leptin levels in patients with antisocial personality disorder

OBJECTIVE

The study aimed to compare acyl ghrelin (AG), des-acyl ghrelin (DAG), and leptin levels considered to be used as biological markers in the etiopathogenesis of antisocial personality disorder (ASPD) with healthy controls, and to investigate the relationship between these hormones and aggression and impulsivity.

METHOD

The study included 45 patients with ASPD and 61 healthy people in the control group. Sociodemographic data form, Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Barratt Impulsiveness Scale (BIS-11), and Buss-Durkee Aggression Scale (BDAS) were applied to all participants. Fasting venous blood samples were taken from all participants at the same time of the day and the height and weight of the participants were measured.

RESULTS

It was found that the mean serum AG and DAG levels were significantly higher than that of healthy controls whereas leptin hormone levels were significantly lower in patients compared to healthy controls. BDI, BAI, BIS-11, and BDAS scores of the patients were significantly higher compared to healthy controls. There was a positive correlation between AG and DAG hormone levels and impulsivity and aggression.

DISCUSSION

The present study is the first in the literature to examine AG, DAG, and leptin hormone levels of patients diagnosed with ASPD. According to the results of the study, it is believed that changes in serum leptin and ghrelin levels will bring a new perspective in terms of understanding the pathophysiological mechanism of ASPD. Further studies are required to explain the definitive roles of these hormones in ASPD.

Lower dietary intake of magnesium is associated with more callous-unemotional traits in children

BACKGROUND

Although researchers increasingly recognize the role of nutrition in mental health, little research has examined specific micronutrient intake in relation to antisocial behavior and callous-unemotional (CU) traits in children. Vitamin B6 and magnesium are involved in neurochemical processes implicated in modulating antisocial behavior and CU traits. The current study examined dietary intakes of magnesium and vitamin B6 in relation to antisocial behavior and CU traits.

METHOD

: We enrolled 11-12 year old children (n = 446, mean age = 11.9 years) participating in the Healthy Brains and Behavior Study. Magnesium and vitamin B6 dietary intake were assessed with three 24-hour dietary recall interviews in children. CU traits and antisocial behavior were assessed by caregiver-reported questionnaires. We controlled for age, sex, race, total energy intake, body mass index, social adversity, ADHD or learning disability diagnosis, and internalizing behavior in all regression analyses.

RESULTS

Children with lower magnesium intake had higher levels of CU traits, controlling for covariates (β = -0.18, B = -0.0066, SE = 0.0027, p < 0.05). Vitamin B6 intake was not significantly associated with CU traits (β = 0.061, B = 0.19, SE = 0.20, p > 0.05). Neither magnesium (β = 0.014, B = 0.0020, SE = 0.0093, p > 0.05) nor vitamin B6 (β = 0.025, B = 0.33, SE = 0.70, p > 0.05) were significantly associated with antisocial behavior.

CONCLUSIONS

Findings suggest that low dietary intake of magnesium may play a role in the etiology of CU traits but not general antisocial behavior. More studies are needed to determine if magnesium supplementation or diets higher in magnesium could improve CU traits in children.

Middle Occipital Area Differentially Associates with Malevolent versus Benevolent Creativity: An fNIRS investigation

This study aimed to explore the neural correlates underlying idea generation during malevolent creativity (MC) using functional near-infrared spectroscopy (fNIRS). Participants were asked to solve problems during three types of creativity tasks: malevolent creativity task (MCT), benevolent creativity task (BCT), and alternative uses task (AUT). fNIRS was used to record individual cerebral activity during the tasks. The results revealed that participants demonstrated weaker neural activation in the right middle occipital area (rMO) and lower neural coupling (NC) between the right frontopolar cortex (rFPC) and rMO during MCT than during BCT and AUT. These suggest that r-MO activity and NC between the rFPC and rMO may distinguish between malevolent and benevolent forms of creative ideation.

Conduct disorder in adolescent females: current state of research and study design of the FemNAT-CD consortium

Conduct disorder (CD) is a common and highly impairing psychiatric disorder of childhood and adolescence that frequently leads to poor physical and mental health outcomes in adulthood. The prevalence of CD is substantially higher in males than females, and partly due to this, most research on this condition has used all-male or predominantly male samples. Although the number of females exhibiting CD has increased in recent decades, the majority of studies on neurobiological measures, neurocognitive phenotypes, and treatments for CD have focused on male subjects only, despite strong evidence for sex differences in the aetiology and neurobiology of CD. Here, we selectively review the existing literature on CD and related phenotypes in females, focusing in particular on sex differences in CD symptoms, patterns of psychiatric comorbidity, and callous-unemotional personality traits. We also consider studies investigating the neurobiology of CD in females, with a focus on studies using genetic, structural and functional neuroimaging, psychophysiological, and neuroendocrinological methods. We end the article by providing an overview of the study design of the FemNAT-CD consortium, an interdisciplinary, multi-level and multi-site study that explicitly focuses on CD in females, but which is also investigating sex differences in the causes, developmental course, and neurobiological correlates of CD.

Salivary cortisol and alpha-amylase diurnal profiles and stress reactivity in children with Attention Deficit Hyperactivity Disorder

There is growing evidence for dysregulation of the stress system in individuals with Attention Deficit Hyperactivity Disorder (ADHD). The stress system includes neuroanatomical and functional components that function in concert to maintain homeostasis and its main effectors are the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic/adrenomedullary nervous system (SNS). As stress system activity demonstrates a distinct circadian variation, we aimed to describe simultaneously, diurnal rhythms of both the HPA axis and the SNS in children with ADHD and a comparison group. Moreover, we attempted to investigate stress responses to a physical stressor, venipuncture, in both groups. Sixty-two prepubertal children with ADHD combined (ADHD-C) or inattentive (ADHD-I) type and 40 typically developing children provided saliva samples at six specific time points during a day, as well as before and 10 min after a scheduled morning venipuncture. Salivary cortisol and α- amylase were selected as reliable noninvasive biomarkers for HPA axis and SNS function and were measured in the samples obtained. Results revealed that children with ADHD-C had lower mean cortisol values both 30 min after awakening and at 18:00 h than controls (p = 0.002 and p = 0.018 respectively), as well as lower mean Cortisol Awakening Response (CAR) and Area Under the Curve for "wake to bed" period (AUC_i) values of cortisol (p = 0.004 and p = 0.001, respectively). Also, mean CAR and cortisol AUC_i were lower in children with ADHD-I than the control group (p = 0.034 and p = 0.038 respectively). Alpha-amylase measurements showed an increase over time (p < 0.001), which was similar in all three groups. Interestingly, α-amylase changes over time were correlated with the corresponding cortisol changes (p < 0.001). Venipuncture, elicited a significant increase only in α-amylase levels and more so in the control group (p = 0.003). These findings suggest a partial hypofunction of the stress system in children with ADHD.

The influence of stress hormones and aggression on cooperative behaviour in subordinate meerkats

In cooperative breeders, aggression from dominant breeders directed at subordinates may raise subordinate stress hormone (glucocorticoid) concentrations. This may benefit dominants by suppressing subordinate reproduction but it is uncertain whether aggression from dominants can elevate subordinate cooperative behaviour, or how resulting changes in subordinate glucocorticoid concentrations affect their cooperative behaviour. We show here that the effects of manipulating glucocorticoid concentrations in wild meerkats (Suricata suricatta) on cooperative behaviour varied between cooperative activities as well as between the sexes. Subordinates of both sexes treated with a glucocorticoid receptor antagonist (mifepristone) exhibited significantly more pup protection behaviour (babysitting) compared to those treated with glucocorticoids (cortisol) or controls. Females treated with mifepristone had a higher probability of exhibiting pup food provisioning (pup-feeding) compared to those treated with cortisol. In males, there were no treatment effects on the probability of pup-feeding, but those treated with cortisol gave a higher proportion of the food they found to pups than those treated with mifepristone. Using 19 years of behavioural data, we also show that dominant females did not increase the frequency with which they directed aggression at subordinates at times when the need for assistance was highest. Our results suggest that it is unlikely that dominant females manipulate the cooperative behaviour of subordinates through the effects of aggression on their glucocorticoid levels and that the function of aggression directed at subordinates is probably to reduce the probability they will breed.

The role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in adolescent aggression

Although numerous studies have examined the neuroendocrinology of aggression, the findings are mixed and focused on cortisol and testosterone. We argue that past findings remain inconclusive partly because the key roles of oxytocin and trauma have not been systematically integrated yet. Oxytocin is associated with social behavior and interacts with cortisol and testosterone, whereas trauma is a crucial risk factor of aggression that strongly affects hormonal activity. In this review, we investigate the role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in aggression during adolescence. We first discuss how these hormones interact with each other and how trauma influences these interactions and then we propose a model that highlights the role of trauma in the hormonal interplay in aggression. We suggest that the timing of trauma has a distinct effect on hormonal activity and it should be integrated into any comprehensive model. Current trauma is linked to different levels of oxytocin, cortisol, testosterone, and testosterone/cortisol ratio than childhood trauma, but this distinction is also influenced by gender and type of aggression. We conclude that in order to better understand the neuroendocrinology of aggression, it is crucial to incorporate the investigation of oxytocin and trauma in future research.

Neural correlates of altered feedback learning in women recovered from anorexia nervosa

Anorexia nervosa (AN) is associated with exaggerated self-control and altered reward-based decision making, but the underlying neural mechanisms are poorly understood. Consistent with the notion of excessive cognitive control, we recently found increased dorsal anterior cingulate cortex (dACC) activation in acutely ill patients (acAN) on lose-shift trials in a probabilistic reversal learning (PRL) task. However, undernutrition may modulate brain function. In attempt to disentangle trait from state factors, the current fMRI study investigated cognitive control in recovered patients (recAN). Thirty-one recAN and 31 healthy controls (HC) completed a PRL task during fMRI. Based on previous findings, we focused on hemodynamic responses during lose-shift behaviour and conducted supplementary functional connectivity analysis. RecAN showed elevated lose-shift behaviour relative to HC. On the neural level, recAN showed normal dACC responses, but increased activation in fronto-parietal control regions. A trend for increased coupling between frontal and parietal regions of interest was also evident in recAN. The current findings in recAN differ from those in our previous study in acAN. While aberrant dACC response to negative feedback may be a correlate of the underweight state in acAN, impaired behavioural adaptation and elevated activation of cognitive control regions in recAN is suggestive of altered neural efficiency.

Interplay between stress response genes associated with attention-deficit hyperactivity disorder and brain volume

The glucocorticoid receptor plays a pivotal role in the brain's response to stress; a haplotype of functional polymorphisms in the NR3C1 gene encoding this receptor has been associated with attention-deficit hyperactivity disorder (ADHD). The serotonin transporter (5-HTT) gene polymorphism 5-HTTLPR is known to influence the relation between stress exposure and ADHD severity, which may be partly because of its reported effects on glucocorticoid levels. We therefore investigated if NR3C1 moderates the relation of stress exposure with ADHD severity and brain structure, and the potential role of 5-HTTLPR. Neuroimaging, genetic and stress exposure questionnaire data were available for 539 adolescents and young adults participating in the multicenter ADHD cohort study NeuroIMAGE (average age: 17.2 years). We estimated the effects of genetic variation in NR3C1 and 5-HTT, stress exposure and their interactions on ADHD symptom count and gray matter volume. We found that individuals carrying the ADHD risk haplotype of NR3C1 showed significantly more positive relation between stress exposure and ADHD severity than non-carriers. This gene-environment interaction was significantly stronger for 5-HTTLPR L-allele homozygotes than for S-allele carriers. These two- and three-way interactions were reflected in the gray matter volume of the cerebellum, parahippocampal gyrus, intracalcarine cortex and angular gyrus. Our findings illustrate how genetic variation in the stress response pathway may influence the effects of stress exposure on ADHD severity and brain structure. The reported interplay between NR3C1 and 5-HTT may further explain some of the heterogeneity between studies regarding the role of these genes and hypothalamic-pituitary-adrenal axis activity in ADHD.

Associations Among Academic Achievement, Attention, and Adrenocortical Reactivity in Caribbean Village Children

This study examined associations among academic achievement problems, attention problems, and cortisol levels in 86 children (ages 5 to 12) in St. Vincent, the West Indies. Findings revealed that morning cortisol levels were more elevated at school than at home. Attention problems contributed negatively to academic scores. Children with the most attention problems showed greater school relative to home cortisol elevations than did other children. Once the variance due to attention problems was accounted for, the interaction between attention problems and cortisol elevation explained additional variance in academic scores. There was some evidence that attention problems and cortisol reactivity were associated. Furthermore, greater cortisol reactivity was correlated with the academic difficulties of children who exhibited more attention problems.

Biologic effects of stress and bonding in mother-infant pairs

OBJECTIVE

Maternal stress in humans influences behavior of children and can be assessed using biological markers. Mothers and their one-month-old infants were recruited from an existing study to examine baseline maternal serum oxytocin and hypothalamic-pituitary-adrenal axis response to infant blood heel stick stress as measured by salivary cortisol in the dyads. Objectives were to explore (1) relationships between mother and infant cortisol levels, (2) gender differences in infant biologic cortisol response, and (3) the association of cortisol levels in the dyads and maternal oxytocin levels

METHODS

Forty-two mother-infant dyads provided biologic samples and self-report data. Maternal oxytocin samples were obtained. Initial salivary cortisol was assessed in both the mother and infant, followed by a heel stick blood draw. Twenty minutes later, salivary cortisol was collected again from dyads.

RESULTS

Self-report measures were negative for depression and risk for childhood neglect. Although oxytocin and baseline cortisol in the infants was higher in mothers that did some breast-feeding, there was no statistically significant difference (p = 0.2 and p = 0.1, respectively). Analyses showed (a) higher baseline cortisol in mothers was related to higher baseline cortisol in infants (p ≤ 0.0001), (b) following the stressor, female infants had a larger positive change in cortisol, after adjusting for baseline cortisol (p = 0.045), and (c) there was no relationship between dyad cortisol levels and maternal oxytocin.

CONCLUSIONS

Maternal and infant biologic stress measures are related. Female infants have a larger hypothalamic-pituitary-adrenal response to a blood draw stressor as measured by salivary cortisol than male infants.

Preditores do Comportamento Antissocial em Adolescentes

RESUMO Este estudo investigou preditores do comportamento antissocial em 142 adolescentes em medida socioeducativa de internação (G1) e 691 estudantes de escolas públicas (G2), que responderam a um questionário. Foram observadas diferenças significativas entre os grupos quanto ao comportamento antissocial, violência intra e extrafamiliar, uso de drogas e eventos estressores, com médias mais altas em G1. Dentre as variáveis investigadas, grupo, uso de drogas e eventos estressores, juntamente com a covariável sexo, explicaram 66,5% da variável dependente. Um modelo de path analysis demonstrou que as variáveis sexo e ambiente estressor, computado pelos eventos estressores, qualidade do relacionamento familiar e violência intra e extrafamiliar predizem o uso de drogas e comportamentos antissociais.

Multidimensional assessment of neuroendocrine and psychopathological profiles in maltreated youth

It has been debated whether children who have experienced early life stress (ELS), such as early caregiver separation show elevated risk for stress-related psychiatric disorders and a multi-symptom psychopathological profile that is not fully reflected in categorical assessments. In this study, we investigated dimensional measures of stress-related psychopathology in children in permanent out-of-home care, taking into account potential neuroendocrine interactions. In the current study, 25 children who had been placed in permanent out-of-home care before age 3 (years) and 26 controls (aged 10.6 ± 1.75 years) were investigated with categorical (DSM-IV) and dimensional assessments (CBCL) of psychopathology and diurnal salivary cortisol levels were assessed. Semi-structured interviews (K-DIPS) revealed no significant group differences in full-scale psychiatric diagnoses, whereas dimensional assessment (CBCL) revealed significant group differences in externalizing and total problem behaviours within the clinical range for children with ELS. Only children with ELS showed a combined symptom profile of clinical-range internalizing and externalizing problems. Lower morning cortisol values and subsequent flatter decline was found in subjects with ELS children compared to controls, showing group differences in diurnal cortisol secretion. Lower morning cortisol values were associated with more problem behaviour in the ELS group. Results show that ELS children exhibited increased psychopathological symptom severity and complexity associated with lower morning cortisol levels, which was not fully reflected in categorical assessments. This highlights the importance of incorporating dimensional assessments and neurobiological factors into psychopathological evaluations of children in out-of-home care in order to facilitate early identification of children at high risk for stress-related disorders.

Neurobiological changes after intervention in individuals with anti-social behaviour: a literature review

BACKGROUND

A neurobiological perspective has become accepted as a valuable approach for understanding anti-social behaviour. There is literature to suggest that, in non-offending populations, psychological treatments affect both neurobiological measures and clinical presentation. A theoretical position to this effect has been adopted with respect to offender treatment, but there has been no systematic review of empirical literature on this point.

AIMS

This study aimed to ascertain from published literature firstly whether there is evidence of change in neuropsychological or physiological measures after behavioural treatments/programmes for people with anti-social behaviour and secondly whether these neurobiological changes are associated with behavioural change.

METHOD

A systematic search strategy was formulated to include studies considering 'neurobiological factors', 'anti-social population', 'treatment' and 'treatment outcome'. The Maryland Scientific Methods Scale was used to select relevant studies of sufficient methodological quality.

RESULTS

Eleven studies were found, only one with adults. Overall, the values of specific neurobiological risk factors, particularly of basal cortisol, become less abnormal following intervention. There was some evidence for a link between change in neurobiological functioning and behavioural improvement.

CONCLUSIONS

Findings, although provisional, may provide new insights into the underlying mechanisms of interventions for anti-social behaviour. Future studies that include pre-treatment neurobiological assessment could help reveal physical vulnerabilities that interventions should target to improve treatment efficacy, and provide for objective, independent corroboration of change.

Age and Gender-Related Changes in Biogenic Amine Metabolites in Cerebrospinal Fluid in Children

Metabolites of cerebrospinal biogenic amines (dopamine and serotonin)are an important tool in clinical research and diagnosis of children with neurotransmitter disorders. In this article we focused on finding relationships between the concentration of biogenic amine metabolites, age, and gender. We analyzed 148 samples from children with drug resistant seizures of unknown etiology and children with mild stable encephalopathy aged 0-18 years. A normal profile of biogenic amineswas found in 107 children and those children were enrolled to the study group. The CSF samples were analyzed by HPLC with an electrochemical detector. The concentrations of the dopamine and serotonin metabolites homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), respectively, were high at birth, gradually decreasing afterward until the 18 years of age. Nevertheless, the HVA/5-HIAA ratio did not vary with age, except in the children below 1 year of age. In the youngest group we observed a strong relationship between the HVA/5-HIAA ratio and age (r = 0.69, p < 0.001). There were no statistical differences in the level of both dopamine and serotonin metabolites between boys and girls, although a tread toward lower HVA and 5-HIAA in the boys was noticeable. Significant inter-gender differences in the level of HVA and 5-HIAA were noted only in the age-group of 1-4 years, with 5-HIAA being higher in the girls than boys (p = 0.004). In conclusion, the study revealed that the concentration of biogenic amine metabolites is age and sex dependent.

Structure of observed temperament in middle childhood

Although much is known about the structure of adult temperament and personality, significantly less is known about the structure of child temperament. We examined the structure of child temperament in 205 seven-year-olds using observational measures. Exploratory factor analysis identified factors representing positive emotionality/sociability, disinhibition/anger, fear/behavioral inhibition, and sadness. The predictive validity of these dimensions was evaluated by examining their associations with children's internalizing and externalizing symptoms: positive emotionality/sociability showed positive associations with ADHD symptoms, disinhibition/anger showed positive associations with externalizing symptoms, fear/behavioral inhibition showed negative associations with ADHD and CD symptoms, and sadness showed positive associations with both internalizing and externalizing problems. These associations were consistent with extant literature on temperament and psychopathology, supporting the validity of the structure obtained.

Mädchen mit Störungen des Sozialverhaltens

Unser Wissen zu Ursachen, Verlauf und Behandlungsoptionen von Patienten mit Störungen des Sozialverhaltens beschränkt sich überwiegend auf Studien an männlichen Patienten. In neueren Untersuchungen werden vermehrt weibliche Patientinnen berücksichtigt und geschlechtsassoziierte Unterschiede überprüft. Die vorliegende Arbeit gibt eine Übersicht über aktuelle Erkenntnisse zum psychopathologischen Erscheinungsbild und den neuropsychologischen Auffälligkeiten bei Mädchen mit Störungen des Sozialverhaltens. Es wird zudem die Frage berücksichtigt, ob auf der Basis der referierten Untersuchungsbefunde auf das Vorliegen geschlechtsspezifischer psychosozialer und neurobiologischer Risikofaktoren zu schließen ist. Implikationen für zukünftige Trends in der Forschung und Möglichkeiten für differentielle Behandlungsoptionen für Mädchen und Jungen werden diskutiert.

Child maltreatment, dating perpetration of physical assault, and cortisol reactivity among disadvantaged female adolescents

OBJECTIVE

Few studies have examined hypothalamic-pituitary-adrenal axis stress reactivity and its relationship to histories of child maltreatment and physical aggression. We examined the relation of a history of childhood sexual abuse (CSA) and perpetration of dating violence to patterns of cortisol change before (resting) and after (reactivity) exposure to a laboratory stressor.

METHODS

In a sample of 40 disadvantaged sexually active female adolescent patients (ages 14-17 years), we collected self-reports of lifetime child maltreatment (5 types) and past-year female perpetration of physical assault (PA) acts toward a romantic partner. We assessed changes in salivary cortisol trajectories during resting and reactivity phases following the viewing of a teen dating violence vignette.

RESULTS

Reports of CSA (CSA+ group) were associated with reports of perpetration of severe dating PA (PA+ group), but the relation of these reports to laboratory-assessed patterns of cortisol changes following the stressor was opposite. As compared with subjects without victimization or perpetration histories (referent group), the CSA+ group showed the most pronounced positive slope (reactivity), whereas the PA+ group showed the least positive slope following the laboratory stressor after the overlap between these groups was statistically adjusted. While showing less reactivity to the laboratory stressor, the PA+ group had higher levels of resting cortisol, which stayed high during reactivity as compared to the referent group.

CONCLUSION

The laboratory paradigm to elicit neuroendocrine stress-related cortisol reactivity appears to be a promising tool for identifying altered cortisol physiology among female adolescents with mixed histories of CSA and perpetration of dating PA.

Störungen des Sozialverhaltens

Dieser Beitrag diskutiert die prädiktive Validität der allgemeinen Diagnosekriterien von Störungen des Sozialverhaltens nach ICD-10 und DSM-IV-TR. Dabei wird Bezug genommen auf aktuelle Befunde, die eine Phänotypisierung früh beginnender Störungen des Sozialverhaltens auf der Basis neurobiologischer und persönlichkeitsspezifischer Faktoren nahelegen. Untersuchungsergebnisse, die auf defizitäre neurobiologische Mechanismen aggressiven Verhaltens in Bezug auf Prozesse der Emotionswahrnehmung und Emotionsregulation hinweisen, werden dargestellt, wobei auch die Bedeutung möglicher mediierender Einflüsse früher psychosozialer Erfahrungen auf neurobiologische Funktionen erörtert wird. Die klinischen Implikationen für die Klassifikation, den Verlauf und die Behandlung von Störungen des Sozialverhaltens werden abschließend diskutiert.

Influence of treatment for disruptive behavior disorders on adrenal and gonadal hormones in youth

The study examined whether psychosocial intervention for children diagnosed with a disruptive behavior disorder (DBD; n = 84) changed concentrations of cortisol and testosterone across a 3-year follow-up when compared to a matched, nonclinical, healthy comparison (HC; n = 69) group. Boys and girls (6-11 years) with a DBD were randomly assigned to one of two arms of a multimethod intervention. Hierarchical linear modeling revealed that children undergoing psychosocial intervention for a DBD experienced a significant decline in diurnal cortisol change over time (p < .05) when compared to the HC condition. Boys with a DBD diagnosis had significantly lower mean cortisol concentrations prior to treatment (p < .05) and showed a significantly steeper increase in mean cortisol over time (p < .05) when compared to HC boys. Treatment effects for diurnal cortisol change were replicated in the boys-only analysis. No treatment effects were noted for testosterone in either analysis.

Cortisol reactivity in boys with attention-deficit/hyperactivity disorder and disruptive behavior problems: the impact of callous unemotional traits

There is a body of literature demonstrating an association between altered hypothalamic pituitary adrenal (HPA) axis reactivity and aggressive behavior. Aggressive and disruptive behavior also is highly prevalent in children with attention deficit/hyperactivity disorder (ADHD). Findings on HPA-axis reactivity in ADHD, however, are rather inconsistent. Specific temperamental risk factors previously were associated with a specific subtype of severe disruptive behavior. These traits might also be characterized by a distinct neurobiological profile across ADHD and disruptive behavior disorders. In this study we focus on psychopathic traits, notably callous unemotional (CU) traits. The main objective of the present study was to investigate whether two groups of ADHD patients with high or low CU traits differed in cortisol reactivity. Subjects were 36 boys with ADHD and disruptive behavior symptoms aged 8 to 14 years. Salivary cortisol probes were taken before and repeatedly after an experimental standardized stress test. Patients scoring high on CU traits showed a blunted HPA axis reactivity to the experimentally induced stress. Results underscore the need to consider specific personality traits in investigating neurobiological correlates in ADHD with disruptive behavior problems.

Exogenous cortisol facilitates responses to social threat under high provocation

Stress is one of the most important promoters of aggression. Human and animal studies have found associations between basal and acute levels of the stress hormone cortisol and (abnormal) aggression. Irrespective of the direction of these changes--i.e., increased or decreased aggressive behavior--the results of these studies suggest dramatic alterations in the processing of threat-related social information. Therefore, the effects of cortisol and provocation on social information processing were addressed by the present study. After a placebo-controlled pharmacological manipulation of acute cortisol levels, we exposed healthy individuals to high or low levels of provocation in a competitive aggression paradigm. Influences of cortisol and provocation on emotional face processing were then investigated with reaction times and event-related potentials (ERPs) in an emotional Stroop task. In line with previous results, enhanced early and later positive, posterior ERP components indicated a provocation-induced enhanced relevance for all kinds of social information. Cortisol, however, reduced an early frontocentral bias for angry faces and--despite the provocation-enhancing relevance--led to faster reactions for all facial expressions in highly provoked participants. The results thus support the moderating role of social information processing in the 'vicious circle of stress and aggression'.

The limbic-hypothalamic-pituitary-adrenal axis and the development of alcohol use disorders in youth

OBJECTIVE

As the initiation and acceleration of alcohol use commonly occurs during adolescence, the etiological basis for this phenomenon is of critical importance. Using the diathesis-stress model as a framework, this review will evaluate the emerging evidence implicating the limbic-hypothalamic-pituitary-adrenal (LHPA) axis in the development of alcohol use disorder (AUD).

METHOD

Searches were conducted of the PubMed/Medline, PsycInfo, PsycBooks, Cochrane and ISI Web of Science databases, using a specified set of search terms.

RESULTS

Genetic liabilities, antenatal stress/anxiety or exposure to addictive substances, exposure to maltreatment or other traumatic events in childhood and psychiatric illness in childhood/adolescence can all increase the risk, or diathesis, for AUD. Greater LHPA dysfunction may serve as a marker for higher diathesis levels in youth. When exposed to stressors in adolescence, high-risk youth (or those with greater LHPA dysfunction) may use alcohol and/or other substances to cope with stressors and, in turn, become more vulnerable to AUD.

CONCLUSION

Evidence suggests that LHPA dysfunction and stress play an important role in the development of AUD. Genetic liabilities, antenatal insults, maltreatment, and psychiatric illness appear to increase LHPA dysfunction, raising risk for AUD. Further research is needed to clarify the complex interplay among adverse developmental experiences, LHPA dysfunction, and the development of AUD in adolescents.

Adverse childhood experiences (ACEs), genetic polymorphisms and neurochemical correlates in experimentation with psychotropic drugs among adolescents

Epidemiological and clinical data show frequent associations between adverse childhood experiences (ACEs) and substance abuse susceptibility particularly in adolescents. A large body of evidences suggests that the possible dysregulation of neuroendocrine responses as well as neurotransmitters function induced by childhood traumatic experiences and emotional neglect could constitute one of the essential biological changes implementing substance abuse vulnerability. Moreover, genotype variables and its environment interactions have been associated with an increased risk for early onset substance abuse. In this paper we present several data that support the hypothesis of the involvement of hypothalamus-pituitary-adrenal (HPA) axis in mediating the combined effect of early adverse experiences and gene variants affecting neurotransmission. The presented data also confirm the relationship between basal plasma levels of cortisol and ACTH, on the one hand, and retrospective measures of neglect during childhood on the other hand: the higher the mother and father neglect (CECA-Q) scores are, the higher the plasma levels of the two HPA hormones are. Furthermore, such positive relationship has been proved to be particularly effective and important when associated with the "S" promoter polymorphism of the gene encoding the 5-HTT transporter, both in homozygote and heterozygote individuals.

Research review: the neurobiology and genetics of maltreatment and adversity

The neurobiological mechanisms by which childhood maltreatment heightens vulnerability to psychopathology remain poorly understood. It is likely that a complex interaction between environmental experiences (including poor caregiving) and an individual's genetic make-up influence neurobiological development across infancy and childhood, which in turn sets the stage for a child's psychological and emotional development. This review provides a concise synopsis of those studies investigating the neurobiological and genetic factors associated with childhood maltreatment and adversity. We first provide an overview of the neuroendocrine findings, drawing from animal and human studies. These studies indicate an association between early adversity and atypical development of the hypothalamic-pituitary-adrenal (HPA) axis stress response, which can predispose to psychiatric vulnerability in adulthood. We then review the neuroimaging findings of structural and functional brain differences in children and adults who have experienced childhood maltreatment. These studies offer evidence of several structural differences associated with early stress, most notably in the corpus callosum in children and the hippocampus in adults; functional studies have reported atypical activation of several brain regions, including decreased activity of the prefrontal cortex. Next we consider studies that suggest that the effect of environmental adversity may be conditional on an individual's genotype. We also briefly consider the possible role that epigenetic mechanisms might play in mediating the impact of early adversity. Finally we consider several ways in which the neurobiological and genetic research may be relevant to clinical practice and intervention.

Exogenous cortisol enhances aggressive behavior in females, but not in males

The hypothalamic-pituitary-adrenal (HPA) axis plays a major role in the development, elicitation, and enhancement of aggressive behavior in animals. Increasing evidence suggests that this is also true for humans. Here, we report on a study of the role of basal and acute HPA axis activity in a sample of 48 healthy male and female adults. We pharmacologically enhanced cortisol levels and used the Taylor Aggression Paradigm (TAP) to induce and measure aggression (divided into three blocks). Participants either received an oral dose of 20 mg hydrocortisone (cortisol group) or a placebo (placebo group). Half of each group received high or low levels of provocation with the TAP, respectively. Before, we assessed the cortisol awakening response as a trait measure of basal HPA axis activity. Participants in the cortisol group reacted more aggressively in the third block of the TAP compared to the placebo group. Furthermore, gender interacted with treatment: only females, but not males showed enhanced aggressive behavior after cortisol administration. There was no significant difference in males between the placebo and cortisol group. Basal HPA axis activity was negatively related to aggressive behavior, but again only in females and most strongly within the placebo group. This study provides the first evidence for a causal involvement of acute HPA axis activation in aggressive behavior in humans.

Abnormal hippocampal shape in offenders with psychopathy

Posterior hippocampal volumes correlate negatively with the severity of psychopathy, but local morphological features are unknown. The aim of this study was to investigate hippocampal morphology in habitually violent offenders having psychopathy. Manual tracings of hippocampi from magnetic resonance images of 26 offenders (age: 32.5 +/- 8.4), with different degrees of psychopathy (12 high, 14 medium psychopathy based on the Psychopathy Checklist Revised), and 25 healthy controls (age: 34.6 +/- 10.8) were used for statistical modelling of local changes with a surface-based radial distance mapping method. Both offenders and controls had similar hippocampal volume and asymmetry ratios. Local analysis showed that the high psychopathy group had a significant depression along the longitudinal hippocampal axis, on both the dorsal and ventral aspects, when compared with the healthy controls and the medium psychopathy group. The opposite comparison revealed abnormal enlargement of the lateral borders in both the right and left hippocampi of both high and medium psychopathy groups versus controls, throughout CA1, CA2-3 and the subicular regions. These enlargement and reduction effects survived statistical correction for multiple comparisons in the main contrast (26 offenders vs. 25 controls) and in most subgroup comparisons. A statistical check excluded a possible confounding effect from amphetamine and polysubstance abuse. These results indicate that habitually violent offenders exhibit a specific abnormal hippocampal morphology, in the absence of total gray matter volume changes, that may relate to different autonomic modulation and abnormal fear-conditioning.

Early life stress, the development of aggression and neuroendocrine and neurobiological correlates: what can we learn from animal models?

Early life stress (child and adolescent abuse, neglect and trauma) induces robust alterations in emotional and social functioning resulting in enhanced risk for the development of psychopathologies such as mood and aggressive disorders. Here, an overview is given on recent findings in primate and rodent models of early life stress, demonstrating that chronic deprivation of early maternal care as well as chronic deprivation of early physical interactions with peers are profound risk factors for the development of inappropriate aggressive behaviors. Alterations in the hypothalamic-pituitary-adrenocortical (HPA), vasopressin and serotonin systems and their relevance for the regulation of aggression are discussed. Data suggest that social deprivation-induced inappropriate forms of aggression are associated with high or low HPA axis (re)activity and a generally lower functioning of the serotonin system in adulthood. Moreover, genetic and epigenetic modifications in HPA and serotonin systems influence the outcome of early life stress and may even moderate adverse effects of early social deprivation on aggression. A more comprehensive study of aggression, neuroendocrine, neurobiological and (epi)genetic correlates of early life stress using animal models is necessary to provide a better understanding of the invasive aggressive deficits observed in humans exposed to child maltreatment.

Children's context inappropriate anger and salivary cortisol

Some children show emotion that is not consistent with normative appraisal of the context and can therefore be defined as context inappropriate (CI). The authors used individual growth curve modeling and hierarchical multiple regression analyses to examine whether CI anger predicts differences in hypothalamic-pituitary-adrenal axis activity, as manifest in salivary cortisol measures. About 23% of the 360 children (ages 6-10 years, primarily 7-8) showed at least 1 expression of CI anger in situations designed to elicit positive affect. Expression of anger across 2 positive assessments was less common (around 4%). CI anger predicted the hypothesized lower levels of cortisol beyond that attributed to context appropriate anger. Boys' CI anger predicted lower morning cortisol and flatter slopes. Results suggest that this novel approach to studying children's emotion across varying contexts can provide insight into affective style.

Genetic risk for conduct disorder symptom subtypes in an ADHD sample: specificity to aggressive symptoms

OBJECTIVE

Recent studies have suggested an association between candidate genes (i.e., COMT, SLC6A4) and conduct disorder (CD). However, it is not clear if these relations extend to CD within the context of attention-deficit/hyperactivity disorder (ADHD). Also, it is uncertain whether the risk is specific to aggressive symptoms or is a risk for CD generally. The aim of this study was to examine the role of the COMT and SLC6A4 genes in the risk for CD and its symptomatic subtypes in the context of ADHD.

METHOD

We examined subjects with ADHD (n = 444, age range 6-55 years) aggregated across four completed studies. Psychiatric diagnoses were determined by structured interviews. We tested the association between genotype and the diagnosis of CD and aggressive and covert symptom counts.

RESULTS

There was no significant association between variations in functional polymorphisms of either the COMT gene or the SLC6A4 gene and the risk for CD. The COMT gene was associated with increased aggressive CD symptoms but not covert CD symptoms. The SLC6A4 gene was not associated with either symptom subtype.

CONCLUSIONS

These findings contribute to our understanding of the genetic basis of antisocial behavior in the ADHD population and provide additional support for the notion that aggressive and covert CD symptom subtypes are etiologically distinct.

Salivary gonadal and adrenal hormone differences in boys and girls with and without disruptive behavior disorders: Contextual variants

Hormone differences by psychopathology group and gender may have implications for understanding disruptive behavior disorders (DBDs) and complexities of treatment outcomes. Current theoretical models emphasize contextual differences as moderators of hormone-behavior relations. This baseline report examined: (a) hormone differences in youth with and without DBD, and (b) contextual factors as moderators of behavior problems and hormones. 180 children and adolescents were enrolled (141 boys, mean 9.0+/-1.7 years). DBD participants met criteria for conduct disorder (CD) and/or oppositional defiant disorder (ODD) (n=111); 69 were recruited as healthy comparisons (HC). Saliva was collected for testosterone, cortisol, dehydroepiandrosterone and androstenedione. DBD youth had significantly higher androstenedione than the HC group. There was a group by gender interaction for basal cortisol mean with DBD boys and HC girls having lower cortisol. Moderating effects of contextual variables (e.g., family functioning, delinquent peers) were noted for cortisol and adrenal androgens. Findings argue for considering hormones as an influence on DBD beyond simple direct one-to-one associations.

Evaluation: A Booming Business but is it Adding Value?1

Evaluation, monitoring, inspection and performance auditing have become a booming business. The numbers of professional societies have strongly increased and there are so many studies that authors recently referred to them as ‘streams’ and ‘fleets’. Evaluation has also been called a ‘positive social epidemic’. This article reveals that the booming business not only has positive consequences and ‘added value’, but also unwanted downsides. ‘Evaluation machines’, ‘death by evaluation’, ‘evaluitis’ and the ‘performance paradox’ are examples.

This article presents three possible explanations for the situation in which a booming business goes hand in hand with the beginnings of diminishing returns of evaluation for society. The first explanation is that evaluations are becoming part of management support systems that produce information that often only reinforces management decisions. The second looks into the unintended and negative consequences of ‘paradigm wars’. And the third suggestion deals with the limited explanatory power of evaluations.

Maternal prenatal smoking, parental antisocial behavior, and early childhood physical aggression

This study investigated joint effects of maternal prenatal smoking and parental history of antisocial behavior on physical aggression between ages 17 and 42 months in a population sample of children born in Québec (N = 1,745). An analysis of variance (ANOVA) showed significant main effects of maternal prenatal smoking and a significant interaction between maternal prenatal smoking and mother's history of antisocial behavior in the prediction of children's probability to display high and rising physical aggression. The interaction indicated that the effects of heavy smoking during pregnancy (> or =10 cigarettes/day) were greater when the mother also had a serious history of antisocial behavior. The effects remained significant after the introduction of control variables (e.g., hostile-reactive parenting, family functioning, parental separation/divorce, family income, and maternal education). Another significant interaction not accounted for by control variables was observed for maternal prenatal smoking and family income, indicating more serious effects of maternal prenatal smoking under relatively low-income, conditions. Both interactions indicate critical adversities that, in combination with maternal prenatal smoking, have supra-additive effects on (the development of) physical aggression during early childhood. These findings may have implications for the selection of intervention targets and strategies.

Treating disruptive behavior disorders with risperidone: a 1-year, open-label safety study in children and adolescents

OBJECTIVE

The aim of this study was to determine the long-term safety of risperidone as maintenance therapy in children and adolescents with disruptive behavior disorders (DBDs) and normal intelligence.

METHOD

An open-label, 1-year extension study was conducted from January, 2002, to July, 2004, in 232 subjects with DBDs (5-17 years) previously randomized to risperidone (RIS) (n = 115, RIS/RIS) or placebo (PLA) (n = 117, PLA/RIS) in a double-blind, 6-month withdrawal study. Adverse events (AEs) and clinical laboratory test results were recorded. Efficacy was assessed using Nisonger Child Behavior Rating Form. Safety and efficacy were evaluated in the intent-to-treat population.

RESULTS

A total of 169/232 (73%) subjects completed the study. Subjects were predominantly male, with a diagnosis of oppositional defiant disorder. Risperidone was generally well tolerated. Weight gain and extrapyramidal symptoms were each reported as AEs by 10 subjects (4.3%). Mean weight z-scores decreased for RIS/RIS subjects (-0.04 +/- 0.28) and increased for PLA/RIS subjects (0.11 +/- 0.43). No subject developed tardive dyskinesia. Prolactin tended to increase with risperidone, although this effect diminished with prolonged use and was infrequently associated with AEs. There were no clinically relevant changes in glucose or lipid metabolism. Clinical improvement in DBD symptoms was observed with flexible risperidone doses, regardless of previous treatment and whether subjects had experienced symptom recurrence.

CONCLUSIONS

Risperidone reinitiated for DBD in children with normal intelligence quotients (IQ) was safe and well tolerated over an additional year of treatment. Patients demonstrated clinical benefits, including those who previously experienced symptom recurrence.

Sex, aggression and impulse control: an integrative account

There is evidence that the male sex and a personality style characterized by low self-control/high impulsivity and a propensity for negative emotionality increase the risk for impulsive aggressive, antisocial and criminal behavior. This article aims at identifying neurobiological factors underlying this association. It is concluded that the neurobiological correlates of impulsive aggression act through their effects on the ability to modulate impulsive expression more generally, and that sex-related differences in the neurobiological correlates of impulse control and emotion regulation mediate sex differences in direct aggression. A model is proposed that relates impulse control and its neurobiological correlates to sex differences in direct aggression.

Acute and constitutive increases in central serotonin levels reduce social play behaviour in peri-adolescent rats

RATIONALE

Serotonin is an important modulator of social behaviour. Individual differences in serotonergic signalling are considered to be a marker of personality that is stable throughout lifetime. While a large body of evidence indicates that central serotonin levels are inversely related to aggression and sexual behaviour in adult rats, the relationship between serotonin and social behaviour during peri-adolescence has hardly been explored.

OBJECTIVE

To study the effect of acute and constitutive increases in serotonin neurotransmission on social behaviour in peri-adolescent rats.

MATERIALS AND METHODS

Social behaviour in peri-adolesent rats (28-35 days old) was studied after genetic ablation of the serotonin transporter, causing constitutively increased extra-neuronal serotonin levels, and after acute treatment with the serotonin reuptake inhibitor fluoxetine or the serotonin releasing agent 3,4-methylenedioxymethamphetamine (MDMA). A distinction was made between social play behaviour that mainly occurs during peri-adolescence, and non-playful social interactions that are abundant during the entire lifespan of rats.

RESULTS

In serotonin transporter knockout rats, social play behaviour was markedly reduced, while non-playful aspects of social interaction were unaffected. Acute treatment with fluoxetine or MDMA dose-dependently inhibited social play behaviour. MDMA also suppressed non-playful social interaction but at higher doses than those required to reduce social play. Fluoxetine did not affect non-playful social interaction.

CONCLUSIONS

These data show that both acute and constitutive increases in serotonergic neurotransmission reduce social play behaviour in peri-adolescent rats. Together with our previous findings of reduced aggressive and sexual behaviour in adult serotonin transporter knockout rats, these data support the notion that serotonin modulates social behaviour in a trait-like manner.

Individual differences in offensive aggression in golden hamsters: a model of reactive and impulsive aggression?

In humans, reactive aggression is associated with impulsivity. The purpose of this study is to relate reactive and impulsive aggression in humans with offensive aggression in animals and identify neurobiological correlates associated with certain forms of the behavior. We predicted that individual differences in offensive aggression are associated with individual differences in impulsivity. Adult male hamsters were repeatedly tested for offensive responses and divided into High-Aggression or Low-Aggression groups. They were then trained and tested under a delay-discounting paradigm to assess impulsivity. High-Aggression animals consistently attacked and bit more frequently and faster, and showed highly repetitive behavior, indicated by repeated attacks per contact bout. In addition, these animals engaged in more fragmented and shorter contact bouts. During impulsivity testing, High-Aggression animals preferred immediate smaller rewards over delayed larger rewards. Furthermore, 5-HT and vasopressin (AVP) innervation was compared between the groups. High-Aggression animals showed decreased 5-HT varicosities in several key brain areas involved in aggressive and/or impulsive behavior and decreased AVP fibers in the anterior hypothalamus. Together, these data show a convergence of behavioral phenotypes through individual differences in offensive aggression and impulsivity. As such, this association provides support for an animal model of reactive and impulsive aggression. Furthermore, this behavioral convergence is supported by a concurrent reduction in 5-HT innervation of brain areas controlling aggression and impulsivity, providing a common neural mechanism for this phenotype.