Pubertal neuromaturation, stress sensitivity, and psychopathology

Divergent stress-induced neuroendocrine and behavioral responses prior to puberty

Following an acute stressor, pre-adolescent rats exhibit a protracted hormonal response compared to adults, while after repeated exposure to the same stressor (i.e., homotypic stress) prepubertal males fail to habituate like adults. Though the neurobehavioral implications of these changes are unknown, studying pubertal shifts in stress reactivity may help elucidate the mechanisms that underlie the increase in stress-related psychological and physiological disorders often observed during adolescence. Here, we investigated hormonal, behavioral, and neural responses of prepubertal (30d) and adult (77d) male rats before, during, or after acute stress (restraint), homotypic stress (repeated restraint) or heterotypic stress (repeated cold exposure followed by restraint). We found that prepubertal males exhibit prolonged corticosterone responses following acute and heterotypic stress, and higher adrenocorticotropic hormone and corticosterone responses after homotypic stress, compared to adults. Despite these significant age-dependent changes in hormonal responsiveness, we found that struggling behavior during restraint was similar at both ages, such that both prepubertal and adult animals exposed to homotypic stress struggled less than animals exposed to either acute or heterotypic stress. Across these different stress paradigms, we found greater neural activation, as indexed by FOS immunostaining, in the prepubertal compared to adult paraventricular nucleus of the hypothalamus, a nucleus integral for initiating the hormonal stress response. Interestingly, however, we did not find any influence of pubertal development on stress-induced activation of the posterior paraventricular thalamic nucleus, a brain region involved in experience-dependent changes in stress reactivity. Collectively, our data indicate that prepubertal and adult males display divergent hormonal, behavioral, and neural responses following a variety of stressful experiences, as well as a distinct dissociation between hormonal and behavioral reactivity in prepubertal males under homotypic conditions.

Common liability to addiction and "gateway hypothesis": theoretical, empirical and evolutionary perspective

BACKGROUND

Two competing concepts address the development of involvement with psychoactive substances: the "gateway hypothesis" (GH) and common liability to addiction (CLA).

METHOD

The literature on theoretical foundations and empirical findings related to both concepts is reviewed.

RESULTS

The data suggest that drug use initiation sequencing, the core GH element, is variable and opportunistic rather than uniform and developmentally deterministic. The association between risks for use of different substances, if any, can be more readily explained by common underpinnings than by specific staging. In contrast, the CLA concept is grounded in genetic theory and supported by data identifying common sources of variation in the risk for specific addictions. This commonality has identifiable neurobiological substrate and plausible evolutionary explanations.

CONCLUSIONS

Whereas the "gateway" hypothesis does not specify mechanistic connections between "stages", and does not extend to the risks for addictions, the concept of common liability to addictions incorporates sequencing of drug use initiation as well as extends to related addictions and their severity, provides a parsimonious explanation of substance use and addiction co-occurrence, and establishes a theoretical and empirical foundation to research in etiology, quantitative risk and severity measurement, as well as targeted non-drug-specific prevention and early intervention.

The Role of Emotional Reactivity, Self-regulation, and Puberty in Adolescents' Prosocial Behaviors

This study was designed to examine the roles of emotional reactivity, self-regulation, and pubertal timing in prosocial behaviors during adolescence. Participants were 850 sixth graders (50% female, Mean age = 11.03, SD = .17) who were followed up at age 15. In hierarchical regression models, measures of emotional reactivity, self-regulation, pubertal timing and their interactions were used to predict (concurrently and over time) adolescents' prosocial behaviors in the home and with peers. Overall, the findings provide evidence for pubertal and temperament based predictors of prosocial behaviors expressed in different contexts. Self-regulation was positively related to both forms of prosocial behavior, concurrently and longitudinally. Emotional reactivity showed moderately consistent effects, showing negative concurrent relations to prosocial behavior with peers and negative longitudinal relations (four years later) to prosocial behavior at home. Some curvilinear effects of temperament on prosocial behaviors were also found. Effects of pubertal timing were found to interact with gender, such that boys who were early maturers showed the highest levels of prosocial behavior at home concurrently. Discussion focuses on the role of temperament-based mechanisms in the expression of prosocial behaviors in different contexts in adolescence.

Age of onset of mental disorders and use of mental health services: needs, opportunities and obstacles

PURPOSE OF REVIEW

In this review, we provide an update of recent studies on the age of onset (AOO) of the major mental disorders, with a special focus on the availability and use of services providing prevention and early intervention.

RECENT FINDINGS

The studies reviewed here confirm previous reports on the AOO of the major mental disorders. Although the behaviour disorders and specific anxiety disorders emerge during childhood, most of the high-prevalence disorders (mood, anxiety and substance use) emerge during adolescence and early adulthood, as do the psychotic disorders. Early AOO has been shown to be associated with a longer duration of untreated illness, and poorer clinical and functional outcomes.

SUMMARY

Although the onset of most mental disorders usually occurs during the first three decades of life, effective treatment is typically not initiated until a number of years later. There is increasing evidence that intervention during the early stages of disorder may help reduce the severity and/or the persistence of the initial or primary disorder, and prevent secondary disorders. However, additional research is needed on effective interventions in early-stage cases, as well as on the long-term effects of early intervention, and for an appropriate service design for those with emerging mental disorders. This will mean not only the strengthening and re-engineering of existing systems, but is also crucial the construction of new streams of care for young people in transition to adulthood.

Executive functioning, cortisol reactivity, and symptoms of psychopathology in girls with premature adrenarche

The study examined the interaction between early maturational timing (measured by premature adrenarche [PA]) and executive functioning and cortisol reactivity on symptoms of psychopathology. The study included 76 girls aged 6 through 8 years (mean = 7.50, SD = 0.85) with PA (n = 40) and on-time adrenarche (n = 36). Girls completed a battery of psychological and neuropsychological tests and blood sampling for cortisol. Parents completed the Child Behavior Checklist. The results demonstrated that girls with PA with lower levels of executive functioning had higher externalizing and anxious symptoms compared to other girls. In addition, girls with PA who demonstrated increases in serum cortisol had higher externalizing symptoms than those with stable patterns. Finally, girls with PA who demonstrated decreases in cortisol reported higher depressive symptoms. The findings from this study provide important information concerning the impact of cognitive functioning and stress reactivity on adjustment to early maturation in girls with PA. The results of this research may inform screening and intervention efforts for girls who may be at greatest risk for emotional and behavioral problems as a result of early maturation.

Linkages between childhood executive functioning and adolescent social functioning and psychopathology in girls with ADHD

We followed an ethnically and socioeconomically diverse sample of preadolescent girls with ADHD (n = 140) and matched comparison girls (n = 88) over a period of 5 years, from middle childhood through early/midadolescence, with the aim of determining whether childhood levels of executive function (EF) would predict adolescent multi-informant outcomes of social functioning and psychopathology, including comorbidity between externalizing and internalizing symptomatology. Predictors were well-established measures of planning, response inhibition, and working memory, along with a control measure of fine motor control. Independent of ADHD versus comparison group status, (a) childhood planning and response inhibition predicted adolescent social functioning and (b) childhood planning predicted comorbid internalizing/externalizing disorders in adolescence. Subgroup status (ADHD-Combined, ADHD-Inattentive, and comparison) moderated the relationship between childhood planning and adolescent internalizing/externalizing comorbidity, with the combined type revealing particularly strong associations between baseline planning and adolescent comorbidity. Mediation analyses indicated that adolescent social functioning mediated the prediction from childhood EF to comorbidity at follow-up; in turn, in the girls with ADHD, adolescent comorbidity mediated the prediction from childhood EF to social functioning at follow-up. We conclude that childhood interventions should target EF impairments in addition to behavioral symptoms.

Adolescence and the reorganization of infant development: a neuro-psychoanalytic model

The psychoanalytic view of adolescence as a phase of turbulence and reorganization occupied a central position in child and adolescent psychiatry until about 1980. The view of adolescence as a silent-transition phase then prevailed and diverged from the psychoanalytic perspective. This article reviews infant and adolescent development using an interdisciplinary, neuro-psychoanalytic model in which psychoanalytic, neurobiological, and developmental perspectives converge and complement each other. Recent empirical research focuses attention on adolescence as a phase in which a far-reaching neurobiological and psychological reorganization takes place. According to the ontogenetic principle of psychoanalysis, the development and organization of the basic psychic functions occur in the first five years of life, while a reorganization takes place in adolescence. Neurobiological research confirms that the basic growth and maturation of the brain occurs in the first five years of life, and that a substantial reorganization in brain development transpires in adolescence. Research also verifies the clinical psychoanalytic concept that neurobiological and psychological maturation in adolescence remain unfinished till approximately age 23. The long-term and late biopsychosocial maturation in adolescence implies that adequate monitoring by parents and school remains necessary. The view that adolescents need to separate, and discover their individuality and independence alone, is unsupported by recent findings. The adolescent must acquire his independence, personal identity, and self-agency ("scaffolding") step by step. It is important that the adolescent knows that his parents are in the background monitoring and intervening as necessary; that he is not entirely alone, adrift and at risk for potential fragmentation. The long-term plasticity of the brain in adolescence implies greater vulnerability for the development of psychopathology, but offers opportunity for psychotherapeutic interventions to have greater impact.

Sensitivity to the depressogenic effect of stress and HPA-axis reactivity in adolescence: a review of gender differences

Adolescence is characterized by major biological, psychological, and social challenges, as well as by an increase in depression rates. This review focuses on the association between stressful experiences and depression in adolescence, and the possible role of the hypothalamus-pituitary-adrenal cortex (HPA-)axis in this link. Adolescent girls have a higher probability to develop depressive symptoms than adolescent boys and preadolescents. Increasing evidence indicates that girls' higher risk of depression is partly brought about by an increased sensitivity for stressful life events, particularly interpersonal stressors, which are highly prevalent in adolescent girls. Genetic risk factors for depression, as well as those for stress sensitivity, are often expressed differently in girls and boys. Also environmental adversity tends to affect girls' stress responses more than those of boys. These gender-specific association patterns have been reported for both sensitivity to stressful life events and HPA-axis responses to social stress. Together, the findings suggest that girls are more malleable than boys in response to internal and external influences. This postulated greater malleability may be adaptive in many circumstances, but also brings along risk, such as an increased probability of depression.

Framework for sex differences in adolescent neurobiology: a focus on cannabinoids

This review highlights the salient findings that have furthered our understanding of how sex differences are initiated during development and maintained throughout life. First we discuss how gonadal steroid hormones organize the framework for sex differences within critical periods of development-namely, during those exposures which occur in utero and post-partum, as well as those which occur during puberty. Given the extensive precedence of sex differences in cannabinoid-regulated biology, we then focus on the disparities within the endogenous cannabinoid system, as well as those observed with exogenously administered cannabinoids. We start with how the expression of cannabinoid CB(1) receptors is regulated throughout development. This is followed by a discussion of differential vulnerability to the pathological sequelae stemming from cannabinoid exposure during adolescence. Next we talk about sex differences in the interactions between cannabinoids and other drugs of abuse, followed by the organizational and activational roles of gonadal steroids in establishing and maintaining the sex dependence in the biological actions of cannabinoids. Finally, we discuss ways to utilize this knowledge to strategically target critical developmental windows of vulnerability/susceptibility and thereby implement more effective therapeutic interventions for afflictions that may be more prevalent in one sex vs. the other.

Adolescent development and risk of injury: using developmental science to improve interventions

In adolescence, there is a complex interaction among physical, cognitive, and psychosocial developmental processes, culminating in greater risk-taking and novelty-seeking. Concurrently, adolescents face an increasingly demanding environment, which results in heightened vulnerability to injury. In this paper, we provide an overview of developmental considerations for adolescent injury interventions based on developmental science, including findings from behavioural neuroscience and psychology. We examine the role that typical developmental processes play in the way adolescents perceive and respond to risk and how this integrated body of developmental research adds to our understanding of how to do injury prevention with adolescents. We then highlight strategies to improve the translation of developmental research into adolescent injury prevention practice, calling on examples of existing interventions including graduated driver licensing.

Invited commentary: understanding brain mechanisms of pain processing in adolescents' non-suicidal self-injury

Whereas non-suicidal self injury (NSSI) is reported in 13-23% of adolescents and is an increasingly studied topic, there has been little investigation into the pathophysiology behind self-injury. This commentary examines recent research into pain and emotional distress to discuss implications for the manner we should understand, research, and treat NSSI in the future. Research indicates that adolescents may be particularly vulnerable to NSSI behaviors due to neurodevelopmental changes in the processing of distress and pain. Additionally, emotional distress and physical pain neural pathways may have been altered in these individuals, leading to the development of NSSI behaviors during adolescence when changes in ongoing brain development may lead to further emotional dysregulation and poor impulse control. Further studies that directly characterize the relationship between emotional distress and physical pain in adolescence, as well as the neural differences between self-injurers and non-self-injurers, are needed.

Religiosity and spirituality during the transition to adulthood

Emerging adults (approximately 18 to 25 years of age) experience heightened self-exploration regarding their beliefs and values, including those concerning religiosity and spirituality. The purpose of this article is to review the literature regarding religiosity and spirituality in emerging adulthood. First, we document developmental advances in physical, cognitive, and psychosocial development that support this exploration along with theoretical and empirical work on how religiosity and spirituality develop during this time period. Second, we examine the research on prevalence rates for and correlates of religiosity and spirituality. Third, we examine socializing agents of religiosity and spirituality that document parents’ indirect role relative to other adults, peers, and the media. Next, we examine the role that culture, community, and gender play in the development and socialization of religious and spiritual beliefs and practices. Lastly, future research directions and implications of the findings are discussed.

Cognitive impairments, emotion, stress, and language in schizophrenia

Language symptoms in schizophrenia are exacerbated by arousal of negative affect; the extent of this effect varies widely among patients. The present study assessed predictors of affective speech reactivity. Based on earlier research, it was expected that speech reactivity would be predicted by a combination of neurocognitive and emotional variables. We assessed patients (n=50) for baseline depression; neurocognitive functioning in the domains of sustained attention, immediate auditory memory, organizational sequencing, and conceptual sequencing ability; and clarity of speech communication in both stress and non-stress conditions. Twenty-three subject-nominated "significant others" (SOs) also participated in the study, and were assessed for levels of expressed emotion (EE) as an index of relationship stressors. Patients, in turn, rated the subjective stressfulness of being in the presence of their SOs, from which the propensity to perceive interpersonal experiences as stressful was calculated by regressing out EE ratings. As predicted, baseline depression and sensitivity to interpersonal stressors were related to affective reactivity of speech, with stress sensitivity mediating the relationship between depression and speech reactivity. Contrary to expectations, baseline neurocognitive functioning was not related to speech reactivity. These findings are discussed in terms of their implications for understanding both schizophrenic language disturbance and stress vulnerability.

Neuromaturation and Adolescent Risk Taking: Why Development Is Not Determinism

In the January 2009 issue of this journal, Males argues that adolescent brain science perpetuates the “myth of adolescent risk taking.” He contends that those who study adolescent neuromaturation are biological determinists who ignore the profound social and environmental forces that influence adolescent behavior to further their own agendas. Males mischaracterizes developmental research and misinterprets public health data. This article analyzes his argument and provides a response based on the evidence. There is significant cross-species evidence that adolescence serves an important developmental function on the road to full maturation and is not merely an oppressive social construction. Research on neuromaturation can help elucidate both the vulnerabilities and tremendous potential of the adolescent brain. It also provides the opportunity to examine the role of social environments in shaping developmental processes and to explore how reasoned understandings of adolescent brain and biological development are being used to inform interventions that scaffold adolescent vulnerabilities.

Invited commentary: understanding brain mechanisms of pain processing in adolescents' non-suicidal self-injury

Whereas non-suicidal self injury (NSSI) is reported in 13-23% of adolescents and is an increasingly studied topic, there has been little investigation into the pathophysiology behind self-injury. This commentary examines recent research into pain and emotional distress to discuss implications for the manner we should understand, research, and treat NSSI in the future. Research indicates that adolescents may be particularly vulnerable to NSSI behaviors due to neurodevelopmental changes in the processing of distress and pain. Additionally, emotional distress and physical pain neural pathways may have been altered in these individuals, leading to the development of NSSI behaviors during adolescence when changes in ongoing brain development may lead to further emotional dysregulation and poor impulse control. Further studies that directly characterize the relationship between emotional distress and physical pain in adolescence, as well as the neural differences between self-injurers and non-self-injurers, are needed.

Thymus as a target tissue of glucocorticoid action: what are the consequences of glucocorticoids thymectomy?

Glucocorticoids represent the most powerful endogenous anti-inflammatory and immunosuppressive effectors, interfering with virtually every step of immunoinflammatory responses. Glucocorticoids are often the most effective therapy in the prevention or suppression of inflammation and other immunologically mediated processes, but their use is limited by systemic side effects induced by the over-production of reactive oxygen species, causing dysregulation of physiological processes. The thymus is an organ with both endocrine and immune functions. Glucocorticoids induce thymocyte apoptosis, causing a profound reduction in thymic mass and volume and inducing hormonal thymectomy. The clinical aspects of glucocorticoid thymectomy are not under enough investigation. These unwanted systemic side effects may be the consequence of prolonged therapeutic application of glucocorticoids and prolonged or chronic activation of the hypothalamic-pituitary adrenal axis, which may lead to increased and prolonged secretion of glucocorticoids. This review will discuss the metabolic effects of glucocorticoids in the context of thymic physiology asthe primary sex hormone-responsive organ.

Paediatric major depressive disorder: neurobiology and implications for early intervention

AIM

Paediatric major depressive disorder (MDD) is associated with chronicity and poor outcomes. The goals of this review are (i) to integrate how developing biological systems contribute to the pathophysiology of paediatric MDD, and (ii) to consider the role of early intervention for depressed youth.

METHODS

A developmental perspective is applied herein to review and integrate key neurobiological systems that are implicated in paediatric MDD. We also review recent treatment research for adolescents with MDD.

RESULTS

Available evidence in paediatric and adult populations support an integrative model for the pathophysiology of MDD that involves fronto-limbic neural circuitry and the neuroendocrine stress response system. Evidence from treatment research supports the efficacy of available treatments modalities, including antidepressant medications, cognitive behavioral therapy, and their combination, for the majority of adolescents with moderate to severe MDD.

CONCLUSIONS

Since the biological systems implicated in MDD mature through adolescence, adolescents may be more susceptible to developing depression but also may be more amenable to treatment interventions. Early identification and treatment of paediatric MDD may be able to divert negative trajectories and lead to improved outcomes.

Early pubertal maturation and internalizing problems in adolescence: sex differences in the role of cortisol reactivity to interpersonal stress

An accumulating body of literature has shown a link between early pubertal maturation and internalizing problems, particularly among girls. Our knowledge is, however, limited with regard to what accounts for this association. Based on a hypothesis that early maturing girls have heightened stress sensitivity that increases the risk of internalizing problems, the present investigation examined the roles of pubertal timing and salivary cortisol reactivity to interpersonal stressors in adolescents' internalizing problems. Results from 110 boys and 106 girls (ages 11-16) indicated that early maturing adolescents had increased internalizing symptoms. Early maturing girls' higher levels of internalizing problems were at least partially attributed to their heightened sensitivity to interpersonal stress. Finally, girls' cortisol reactivity to interpersonal challenge was more strongly associated with internalizing problems than boys' reactivity.

Chronic stress and stressful life events in the offspring of parents with bipolar disorder

BACKGROUND

The stress generation theory suggests that depressed individuals and children of depressed mothers are prone to create stressors that are interpersonal and dependent on their own behaviour. Exposure to "self-generated" stress is believed to increase the risk for onset and recurrence of depression. Much less is known about stress in the offspring of parents with bipolar disorder (OBD).

METHODS

As part of a longitudinal study, 37 OBD and 33 offspring of parents with no affective disorder (13 to 26 years old) were interviewed using the UCLA Life Stress Interview, assessing their current life circumstances (chronic stress) and recent negative life events (episodic stress).

RESULTS

The OBD reported more difficulties in interpersonal and non-interpersonal domains of chronic stress than controls. The group differences remained significant after controlling for the presence of affective disorders, indicating that the effect of risk status on chronic stress is independent of the problems associated with having a disorder. With respect to episodic stress, the OBD were 3.9 times more likely to have experienced a moderate to severe interpersonal stressor compared to the control group. There was no group difference for dependent events, but the OBD experienced more severe independent events than controls.

LIMITATIONS

Methodological limitations include a small sample size, large age range, and the absence of parent-reported stress and symptomatology.

CONCLUSIONS

Although the findings do not support the stress generation theory, they suggest that elevated levels of episodic and chronic stress may be important markers of risk for affective disorders in high-risk participants.

Heightened stress responsiveness and emotional reactivity during pubertal maturation: Implications for psychopathology

The onset of adolescence, and more specifically the advent of pubertal maturation, represents a key developmental window for understanding the emergence of psychopathology in youth. The papers in this special section examine normative differences in the neurobiology of stress and emotional functioning over the peripubertal period. The work in this special section helps to fill in gaps in our understanding of key mechanisms that may contribute to increased vulnerabilities in behavioral and psychiatric morbidity during this developmental period.

Heightened stress responsivity and emotional reactivity during pubertal maturation: Implications for psychopathology

This commentary reviews and reflects on the studies of this special section: studies that collectively provide compelling evidence for meaningful changes in stress- and emotionally reactive psychophysiological systems with the transition from middle childhood into adolescence. The observed changes were complex and often overlaid upon ontogenetic differences in basal levels of activation of these systems. Maturational increases in responsiveness to stressors were stressor dependent and differentially expressed across autonomic and hormonal measures. Pubertal status increased the impact of some affective valence manipulations, although not significantly influencing others, including negative affect-related potentiation of startle/reflexes. Such ontogenetic increases in stressor and affect sensitivity may have implications for developmental psychopathology. Developmental increases in stressor reactivity may normally aid youth in responding adaptively to the challenges of adolescence, but may result in stress dysregulation among at-risk adolescents, increasing further their vulnerability for psychopathology. Pubertal-related increases in sensitivity to emotionally laden stimuli may exacerbate individual predispositions for exaggerated affective processing, perhaps contributing to the emergence of psychological disorders in these youth. Together, these studies, with their innovative use of autonomic, reflexive, and hormonal measures to index age- and pubertal-related changes in reactivity to stressors and affective stimuli, provide promising directions for future research. Some of these, along with a few cautionary notes, are outlined.

Stress and the hypothalamic pituitary adrenal axis in the developmental course of schizophrenia

Diathesis-stress models of schizophrenia and other psychotic disorders have dominated theorizing about etiology for over three decades. More recently, with advances in our understanding of the biological processes mediating the effects of stress, these models have incorporated mechanisms to account for the adverse impact of stress on brain function. This review examines recent scientific findings on the role of the hypothalamic-pituitary-adrenal (HPA) axis, one of the primary neural systems triggered by stress exposure, in the expression of vulnerability for schizophrenia. The results indicate that psychotic disorders are associated with elevated baseline and challenge-induced HPA activity, that antipsychotic medications reduce HPA activation, and that agents that augment stress hormone (cortisol) release exacerbate psychotic symptoms. The cumulative findings are discussed in light of a neural diathesis-stress model that postulates that cortisol has the potential to increase activity of dopamine pathways that have been implicated in schizophrenia and other psychotic disorders.

Differences in endocrine parameters and psychopathology in girls with premature adrenarche versus on-time adrenarche

Girls with premature adrenarche (PA) are at risk for multiple problems related to exaggerated androgen synthesis. Whether PA carries a risk of psychopathology remains unknown. This study examined group differences in: (a) anthropometric and endocrine parameters, and (b) mood and behavior problems, in 6-8 year-old girls with PA (n = 40) compared to on-time adrenarche girls (n = 36). PA girls were taller (p < or =0.05) and heavier (p < or =0.01) than the on-time adrenarche girls but body mass index showed no difference. PA girls had significantly (p <0.05) higher adrenal androgen and testosterone concentrations but not cortisol or leptin. PA girls also had significantly more oppositional defiant disorder, and higher symptom counts reflecting anxiety, mood or disruptive behavior disorders. PA girls may be more vulnerable to psychopathology than on-time adrenarche girls. The challenge of future studies is to determine which PA girls are at risk for psychopathology and which are more resilient.

A Social Neuroscience Perspective on Adolescent Risk-Taking

This article proposes a framework for theory and research on risk-taking that is informed by developmental neuroscience. Two fundamental questions motivate this review. First, why does risk-taking increase between childhood and adolescence? Second, why does risk-taking decline between adolescence and adulthood? Risk-taking increases between childhood and adolescence as a result of changes around the time of puberty in the brain's socio-emotional system leading to increased reward-seeking, especially in the presence of peers, fueled mainly by a dramatic remodeling of the brain's dopaminergic system. Risk-taking declines between adolescence and adulthood because of changes in the brain's cognitive control system - changes which improve individuals' capacity for self-regulation. These changes occur across adolescence and young adulthood and are seen in structural and functional changes within the prefrontal cortex and its connections to other brain regions. The differing timetables of these changes make mid-adolescence a time of heightened vulnerability to risky and reckless behavior.

Daytime cortisol and stress reactivity in the offspring of parents with bipolar disorder

The hypothalamic-pituitary-adrenal (HPA) axis is compromised in major depression and bipolar disorder (BD). It is not known however whether HPA abnormalities predate the onset of these disorders. Preliminary data indicated that the adolescent offspring of parents with BD (high-risk), as compared to adolescents of parents with no mental disorder (low-risk), had higher levels of daytime salivary cortisol. The present study re-examined the cortisol increase after awakening and basal cortisol levels in a larger sample, and tested the hypothesis that high-risk offspring are more reactive to psychosocial stress than low-risk offspring. Saliva samples were collected from 58 adolescents, 29 high-risk (14 male/15 female, 16.8 years) and 29 (14 male/15 female, 16.6 years) low-risk, in their natural environment during at least two days. Twenty-five high-risk (13 male/12 female) and 25 low-risk (13 male/12 female) youth completed a child adaptation (15 years) or the standard version of the "Trier Social Stress Test". Consistent with our previous finding, high-risk offspring had higher daytime levels of cortisol in their natural environment than low-risk offspring, and the difference was unrelated to clinical symptoms or other known confounds. Irrespective of risk status, female participants had higher daytime levels of cortisol than male participants. In contrast, there were no group differences in the cortisol response to the laboratory psychosocial stressor. The offspring of parents with BD show evidence of increased daytime basal HPA functioning with normal reactivity to psychosocial stress.

Cortisol, dehydroepiandrosterone sulphate and dehydroepiandrosterone sulphate/cortisol ratio responses to physical stress in males are influenced by pubertal development

To evaluate the influence of chronological age and pubertal development on the hypothalamus-pituitary-adrenal (HPA) axis response to stress, we studied the possible correlations between male pubertal characteristics and salivary cortisol (C), DHEAS and the DHEAS/C ratio before (pre-stress) and after acute exercise-stress in young male volunteers (no. 87; 13.3+/-2.1 yr). In our overall study population, the mean pre-stress salivary C and DHEAS concentrations, significantly increased after exercise-related stress, whereas the DHEAS/C ratio significantly decreased. Pre-stress salivary C was positively correlated with chronological age, and after-stress salivary C concentration variations were negatively correlated with pubertal stage, mean testis volume and pre-stress salivary DHEAS. Furthermore, salivary DHEAS concentrations and the DHEAS/C ratio, before and after exercise stress, were positively correlated with chronological age, pubertal stage, pre-stress salivary testosterone (T), testis volume and body mass index (BMI). In contrast with late pubertal stages (P4, P5), young individuals at early stages of puberty (P1 to P3) showed higher C increase and lower DHEAS/C ratio after exercise-related stress. In conclusion, since C is also a mediator of stress-related negative effects on health and the DHEAS/C ratio has been hypothesized as an index for the degree to which an individual is buffered against the negative effects of stress, these data might suggest potentially increased stress-related risks at early stages of male puberty.

Temperament as a predictor of internalising and externalising problems in adolescent children of parents diagnosed with cancer

Objective

This study examined the relationship between temperament and internalising and externalising problems among children of parents diagnosed with cancer, beyond the effects of socio-demographics, illness-related variables and life events.

Materials and methods

Three hundred and forty adolescent children and their 212 parents diagnosed with cancer participated. Children and parents completed the Youth Self Report and the Child Behaviour Checklist, respectively. Children completed also the Early Adolescent Temperament Questionnaire.

Main results

Daughters of parents with cancer were reported as having more internalising problems than their counterparts did. Prevalence of problems did not depend on children’s and parents’ age or educational level. Recurrent disease and number of life events experienced by children and parents affected the problems reported. The most important temperament dimensions in the prediction of internalising problems in children were shyness and fear/worry, to a lesser extent, frustration and perceptual sensitivity (children only) and lower scores on pleasure intensity (parents only). Externalising problems were associated with effortful control and in children’s reports with frustration. Temperament seemed to be a more important predictor of problems reported by children than parents.

Conclusion

Findings suggest that temperament is useful in determining the relative vulnerability of children of parents who have been diagnosed with cancer. Social workers may help parents to recognise individual differences between children and to support children by using techniques that are compatible with the temperament of children.

Continuities and discontinuities in psychopathology between childhood and adult life

The possible mechanisms involved in continuities and discontinuities in psychopathology between childhood and adult life are considered in relation to the findings from systematic, prospective, long-term longitudinal studies. Findings on schizophrenia, neurodevelopmental disorders, emotional disturbances, antisocial behaviour and substance abuse are used as conditions illustrating the key issues. The overarching themes are then discussed in relation to heterotypic continuity and psychopathologic progression, early age at onset and a range of possible mediating mechanisms - including genetic mediation, 'kindling' effects, environmental influences, coping mechanisms and cognitive processing of experiences. Some of the key research challenges that remain concern the testing of competing hypotheses on mediating processes, the changes involved in adolescence, the transition from prodromal phase to overt schizophrenia and the emergence of adolescent-limited antisocial behaviour. Greater use needs to be made of genetic research strategies and of the testing of possible cognitive processing mediation effects.