A longitudinal analysis of puberty-related cortical development.

The brain undergoes extensive structural changes during adolescence, concurrent to puberty-related physical and hormonal changes. While animal research suggests these biological processes are related to one another, our knowledge of brain development in humans is largely based on age-related processes. Thus, the current study characterized puberty-related changes in human brain structure, by combining data from two longitudinal neuroimaging cohorts. Beyond normative changes in cortical thickness, we examined whether individual differences in the rate of pubertal maturation (or "pubertal tempo") was associated with variations in cortical trajectories. Participants (N = 192; scans = 366) completed up to three waves of MRI assessments between 8.5 and 14.5 years of age, as well as questionnaire assessments of pubertal stage at each wave. Generalized additive mixture models were used to characterize trajectories of cortical development. Results revealed widespread linear puberty-related changes across much of the cortex. Many of these changes, particularly within the frontal and parietal cortices, were independent of age-related development. Males exhibiting faster pubertal tempo demonstrated greater thinning in the precuneus and frontal cortices than same-aged and -sex peers. Findings suggest that the unique influence of puberty on cortical development may be more extensive than previously identified, and also emphasize important individual differences in the coupling of these developmental processes.

Associations between early life stress and anterior pituitary gland volume development - A novel index of long-term hypothalamic-pituitary-adrenal axis functioning.

Previous research has established associations between early life stress (ELS) and altered pituitary gland volume (PGV) growth during adolescence. The pituitary gland, however, is composed of an anterior and a posterior lobe with distinct histological and neuroendocrinological properties. While the anterior (but not posterior) pituitary gland is directly involved in the hypothalamic-pituitary-adrenal axis (HPAA) stress response, no studies have examined the effects of ELS on anterior PGV (aPGV). The present study investigated whether previously reported associations between ELS and PGV development during adolescence were driven by aPGV versus posterior PGV (pPGV). Ninety-one adolescents (49 males) were included from a longitudinal, community-based adolescent development study investigating risk for psychopathology. ELS (maternal affective behavior, childhood maltreatment, stressful life events) was assessed during early adolescence. Participants underwent two waves of structural magnetic resonance imaging during mid- and late-adolescence, and aPGV and pPGV were manually traced. Regression analyses showed that childhood maltreatment predicted greater aPGV growth in females. This finding was stronger than that previously reported for PGV. No associations were found between ELS and pPGV development. Neither aPGV nor pPGV changes mediated associations between ELS and psychopathology. Results suggest that ELS may accelerate aPGV (but not pPGV) growth throughout adolescence. Investigating the development of aPGV, rather than PGV, represents a novel approach to studying the effects of stress on HPAA functioning.

Pubertal hormones predict sex-specific trajectories of pituitary gland volume during the transition from childhood to adolescence.

Pituitary gland volume (PGV) increases during childhood and adolescence in a sex-specific manner, and previous research suggests that puberty may be associated with PGV development. However, existing research to date has focused on sex hormones associated with gonadarche. Given the role of the pituitary gland in hypothalamic-pituitary-adrenal (HPA) axis function, the present study investigated associations between PGV development and HPA hormones that play a role in the earlier pubertal phase of adrenarche. Participants were a community sample of 249 children and early adolescents who participated in longitudinal brain imaging and pubertal assessments. Each participant provided data at one or two waves 1.5-3 years apart, resulting in 409 datasets that covered the age range 8-13 years. PGV was estimated from T1-weighted Magnetic Resonance Imaging (MRI) scans, and dehydroepiandrosterone (DHEA), its sulfate (DHEA-S) and testosterone were measured from saliva. Estradiol was measured for a subset of females. Parents reported on physical pubertal development. Linear mixed modeling was used to investigate associations between age, pubertal measures and PGV development. DHEA, DHEA-S and testosterone (in addition to physical maturation) explained variance in PGV development over and above age, and in a sex-dependent fashion. In all cases, associations were stronger, or only present in females. Estradiol was associated with PGV in females, but this did not appear to account for adrenarcheal hormone effects. Our findings suggest a key role for the hormones of adrenarche, the first biochemical phase of puberty, in PGV development. Further research is required to understand the sex-specific role of adrenarcheal and gonadarcheal hormones on the PGV across development.

Adrenarcheal hormone-related development of white matter during late childhood.

The aim of the current study was to longitudinally examine how adrenarcheal hormones influence the development of white matter structure from age 8.5 to 10 years. Participants were 120 children (66 female; mean age 8.45 years at Time 1 and 9.97 years at Time 2) who completed two diffusion-weighted imaging scans 1.5 years apart. Morning saliva samples were taken at both assessment time points to measure levels of dehydroepiandrosterone (DHEA), its sulphate (DHEAS), and testosterone. Fixel-based analysis was performed to examine how changes in white matter fibre density (FD) and cross-section (FC) over time were associated with initial levels of hormones, and changes in hormone levels over time. Both FD and FC increased over time in a wide range of white matter tracts. Increases in testosterone over time were related to relatively weaker increases in FC in the inferior fronto-occipital fasciculus. Levels and change in DHEA and DHEAS were not related to FD or FC changes. The results demonstrated development of white matter fibre density and cross-section from age 8.5 to 10 years. Changes in adrenarcheal hormone levels showed limited, localized associations with development of white matter FC. Future research should examine the relevance of adrenarcheal hormone-related white matter development for cognitive functioning; as well as directly compare analysis techniques of white matter structure.

Parenting × Brain Development interactions as predictors of adolescent depressive symptoms and well-being: Differential susceptibility or diathesis-stress?

It is unclear how individual differences in parenting and brain development interact to influence adolescent mental health outcomes. This study examined interactions between structural brain development and observed maternal parenting behavior in the prediction of adolescent depressive symptoms and psychological well-being. Whether findings supported diathesis-stress or differential susceptibility frameworks was tested. Participants completed observed interactions with their mothers during early adolescence (age 13), and the frequency of positive and aggressive maternal behavior were coded. Adolescents also completed structural magnetic resonance imaging scans at three time points: mean ages 13, 17, and 19. Regression models analyzed interactions between maternal behavior and longitudinal brain development in the prediction of late adolescent (age 19) outcomes. Indices designed to distinguish between diathesis-stress and differential susceptibility effects were employed. Results supported differential susceptibility: less thinning of frontal regions was associated with higher well-being in the context of low levels of aggressive maternal behavior, and lower well-being in the context of high levels of aggressive maternal behavior. Findings suggest that reduced frontal cortical thinning during adolescence may underlie increased sensitivity to maternal aggressive behavior for better and worse and highlight the importance of investigating biological vulnerability versus susceptibility.

Interaction between hypothalamic-pituitary-adrenal axis genetic variation and maternal behavior in the prediction of amygdala connectivity in children.

High levels of negative, and low levels of positive parenting behaviors can increase the risk of internalizing symptoms in children, but the mechanisms underlying this association are still unclear. One possibility is that parenting behaviors affect the neural correlates of emotion processing in children. Further, genetic variants relevant to the function of the hypothalamic-pituitary-adrenal (HPA) axis are thought to moderate the effect of early experiences on the brain circuits underlying emotion processing, particularly those involving the amygdala. However, no studies have investigated the interactive effect of parenting behaviors and HPA axis-related genes on amygdala activity and connectivity during emotion processing, and in turn internalizing symptoms in children. Participants comprised 80 children (46 females, mean age = 10.0 years) from the community. Observational measures of maternal behavior were collected during mother-child interactions. Children underwent functional magnetic resonance imaging while performing an implicit emotion-processing task, and mothers and children completed measures of child internalizing symptoms. Genetic risk was calculated using an HPA genetic risk score. HPA genetic risk score was indirectly associated with greater child self-reported depressive symptoms via increased amygdala-precuneus connectivity during the emotion-processing task, and interacted with negative maternal parenting behavior to predict increased connectivity between amygdala and superior frontal gyrus, anterior cingulate cortex and parietal cortex. HPA-related genetic variation appears to moderate the effect of negative maternal parenting behavior on the neural underpinnings of emotion processing in children, and may confer risk for depressive symptoms via modulation of amygdala connectivity.

Sometimes It's Good to be Short: The Serotonin Transporter Gene, Positive Parenting, and Adolescent Depression.

In threatening environments, the short (S) allele of 5-HTTLPR is proposed to augment risk for depression. However, it is unknown whether 5-HTTLPR variation increases risk for depression in environments of deprivation, lacking positive or nurturant features. Two independent longitudinal studies (n = 681 and 176, respectively) examined whether 5-HTTLPR moderated associations between low levels of positive parenting at 11-13 years and subsequent depression at 17-19 years. In both studies only LL homozygous adolescents were at greater risk for depression with decreasing levels of positive parenting. Thus, while the S allele has previously been identified as a susceptible genotype, these findings suggest that the L allele may also confer sensitivity to depression in the face of specific environmental challenges.

Measurement of cortisol, dehydroepiandrosterone, and testosterone in the hair of children: Preliminary results and promising indications.

Hormone analysis is a valuable tool for understanding how physiology and behavior interact. Cortisol in hair has recently been examined as a measure of longer-term hormone output. The aim of this study was to investigate the relationships between other androgens in hair and anthropometric measures. In a child sample (n = 114, mean age: 8.5 years, 66 females) levels of cortisol, dehydroepiandrosterone (DHEA) and testosterone were assayed in the 0-3 cm section proximal to scalp. The 3-6 cm segment within a subsample of female participants (n = 35) was examined and compared. Results showed that testosterone strongly correlated with DHEA, and moderately correlated with cortisol (0-3 cm only). Higher hormone concentrations were present in the 3-6 cm segment. Finally, there was a weak positive association between DHEA and height. The replication of previously identified associations between androgens, particularly testosterone-DHEA, and with developmental measures suggests hair may offer a valid method of hormone measurement for DHEA and testosterone.

Who benefits from adolescent sleep interventions? Moderators of treatment efficacy in a randomized controlled trial of a cognitive-behavioral and mindfulness-based group sleep intervention for at-risk adolescents.

BACKGROUND: The aim of this study was to test moderators of therapeutic improvement in an adolescent cognitive-behavioral and mindfulness-based group sleep intervention. Specifically, we examined whether the effects of the program on postintervention sleep outcomes were dependent on participant gender and/or measures of sleep duration, anxiety, depression, and self-efficacy prior to the interventions. METHOD: Secondary analysis of a randomized controlled trial conducted with 123 adolescent participants (female = 59.34%; mean age = 14.48 years, range 12.04-16.31 years) who had elevated levels of sleep problems and anxiety symptoms. Participants were randomized into either a group sleep improvement intervention (n = 63) or group active control 'study skills' intervention (n = 60). The sleep intervention ('Sleep SENSE') was cognitive behavioral in approach, incorporating sleep education, sleep hygiene, stimulus control, and cognitive restructuring, but also had added anxiety-reducing, mindfulness, and motivational interviewing elements. Components of the active control intervention ('Study SENSE') included personal organization, persuasive writing, critical reading, referencing, memorization, and note taking. Participants completed the Pittsburgh Sleep Quality Index (PSQI), Spence Children's Anxiety Scale (SCAS), Center for Epidemiologic Studies Depression Scale (CES-D), and General Self-Efficacy Scale (GSE) and wore an actigraph and completed a sleep diary for five school nights prior to the interventions. Sleep assessments were repeated at postintervention. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12612001177842; http://www.anzctr.org.au/TrialSearch.aspx?searchTxt=ACTRN12612001177842&isBasic=True). RESULTS: The results showed that compared with the active control intervention, the effect of the sleep intervention on self-reported sleep quality (PSQI global score) at postintervention was statistically significant among adolescents with relatively moderate to high SCAS, CES-D, and GSE prior to the intervention, but not among adolescents with relatively low SCAS, CES-D, and GSE prior to the intervention. The results were consistent across genders. However, the effects of the sleep intervention on actigraphy-measured sleep onset latency and sleep diary-measured sleep efficiency at postintervention were not dependent on actigraphy-measured total sleep time, SCAS, CES-D, or GSE prior to the intervention. CONCLUSIONS: This study provides evidence that some sleep benefits of adolescent cognitive-behavioral sleep interventions are greatest among those with higher levels of anxiety and depressive symptoms, suggesting that this may be an especially propitious group to whom intervention efforts could be targeted. Furthermore, adolescents with lower levels of self-efficacy may need further targeted support (e.g. additional motivational interviewing) to help them reach treatment goals.

Cortico-amygdalar maturational coupling is associated with depressive symptom trajectories during adolescence.

BACKGROUND: Adolescence is characterized by increasing prevalence of depressive symptomatology, along with significant structural brain development. While much research has examined focal abnormalities in gray matter structure underlying depression, we employed a structural coupling approach to examine whether longitudinal associations between amygdala and cortical development (referred to as maturational coupling) was related to concurrent changes in depressive symptomatology during adolescence. METHOD: 166 participants underwent up to three MRI scans (367 scans) between 11 and 20 years of age. Depressive symptoms were measured at three coinciding time points using the Center for Epidemiological Studies-Depression scale. Linear mixed models were employed to identify whether change in amygdala volume was related to development of cortical thickness, and if maturational coupling of these regions was related to changes in depressive symptomatology. RESULTS: Positive maturational coupling was identified between the right amygdala and (predominantly anterior) prefrontal cortex, as well as parts of the temporal cortices. Greater positive coupling of these regions was associated with reductions in depressive symptoms over time. CONCLUSIONS: Findings highlight significant associations between cortico-amygdalar maturational coupling and the emergence of depressive symptoms during adolescence, suggesting that synchronous development of these regions might support more adaptive affect regulation and functioning.

The Interaction of Childhood Maltreatment, Sex, and Borderline Personality Features in the Prediction of the Cortisol Awakening Response in Adolescents.

AIMS: The study aimed to investigate childhood maltreatment, sex, and borderline personality disorder (BPD) symptoms as prospective predictors of adolescent hypothalamic-pituitary-adrenal (HPA) axis reactivity. METHOD: A sample of 69 adolescents (30 female and 39 male) were selected from a larger longitudinal study of adolescent development and assessed at 3 time points. BPD symptoms were assessed at T1 (approx. 12.5 years), childhood maltreatment was assessed at T2 (approx. 14.9 years), and multiple assessments of salivary cortisol (cortisol awakening response; CAR) were undertaken at T3 (approx. 15.5 years). RESULTS: Multivariate linear regression analysis revealed a significant main effect for childhood maltreatment but not for early BPD symptoms as a predictor of lower CAR in adolescence (p = 0.047). The association between childhood maltreatment and attenuated CAR was moderated by both early BPD symptoms (p = 0.024; no childhood maltreatment-dependent attenuation of CAR in the presence of BPD symptoms) and sex (p = 0.012; childhood maltreatment-dependent attenuation of CAR in females only). Furthermore, a 3-way BPD × childhood maltreatment × sex interaction (p = 0.041) indicated that the moderating effect of BPD symptoms was present in females only. CONCLUSION: These findings indicate that attenuation of the HPA axis occurs as a response to early maltreatment rather than being related to the early occurrence of BPD pathology. Traumatized female individuals with BPD symptoms might bypass adaptive HPA axis attenuation.

Longitudinal Trajectories of Depression Symptoms in Adolescence: Psychosocial Risk Factors and Outcomes.

Variations in symptom trajectories within a population may represent distinct groups with different etiologies and outcomes. This study aimed to identify subgroups of depression symptom trajectories in a sample of adolescents, and to describe psychosocial attributes of the different groups. In a longitudinal study, 243 adolescents (121 males and 122 females), were assessed using a battery of measures of temperament, psychopathology, and psychological and behavioral functioning. Four phases of data collection over 7 years spanned average ages of the participants from 12 to 18 years old. Depressive symptoms from each phase were used to model latent class growth trajectories. A 4-group solution was selected as the best-fitting model: (1) ongoing stable low levels of depression; (2) very high depressive symptoms initially, but a steep decrease in symptoms over time; (3) moderately high depressive symptoms initially, but symptoms decreased over time; and (4) initially low levels of symptoms that increased over time. Trajectory group membership was associated with a range of psychosocial variables including temperament, childhood maltreatment, and young adult quality of life. Characterising these subgroups allows for a better understanding of how the interaction of risk factors increases the likelihood of depression and other poor outcomes, and highlights the importance of early interventions to prevent and treat adolescent depression.

Brain development during adolescence: A mixed-longitudinal investigation of cortical thickness, surface area, and volume.

What we know about cortical development during adolescence largely stems from analyses of cross-sectional or cohort-sequential samples, with few studies investigating brain development using a longitudinal design. Further, cortical volume is a product of two evolutionarily and genetically distinct features of the cortex - thickness and surface area, and few studies have investigated development of these three characteristics within the same sample. The current study examined maturation of cortical thickness, surface area and volume during adolescence, as well as sex differences in development, using a mixed longitudinal design. 192 MRI scans were obtained from 90 healthy (i.e., free from lifetime psychopathology) adolescents (11-20 years) at three time points (with different MRI scanners used at time 1 compared to 2 and 3). Developmental trajectories were estimated using linear mixed models. Non-linear increases were present across most of the cortex for surface area. In comparison, thickness and volume were both characterised by a combination of non-linear decreasing and increasing trajectories. While sex differences in volume and surface area were observed across time, no differences in thickness were identified. Furthermore, few regions exhibited sex differences in the cortical development. Our findings clearly illustrate that volume is a product of surface area and thickness, with each exhibiting differential patterns of development during adolescence, particularly in regions known to contribute to the development of social-cognition and behavioral regulation. These findings suggest that thickness and surface area may be driven by different underlying mechanisms, with each measure potentially providing independent information about brain development. Hum Brain Mapp 37:2027-2038, 2016. © 2016 Wiley Periodicals, Inc.

Cognitive Control as a Moderator of Temperamental Motivations Toward Adolescent Risk-Taking Behavior.

Few studies have directly examined whether cognitive control can moderate the influence of temperamental positive and negative affective traits on adolescent risk-taking behavior. Using a combined multimethod, latent variable approach to the assessment of adolescent risk-taking behavior and cognitive control, this study examined whether cognitive control moderates the influence of temperamental surgency and frustration on risk-taking behavior in a sample of 177 adolescents (Mage = 16.12 years, SD = 0.69). As predicted, there was a significant interaction between cognitive control and frustration, but not between cognitive control and surgency, in predicting risk-taking behavior. These findings have important implications and suggest that the determinants of adolescent risk taking depend on the valence of the affective motivation for risk-taking behavior.

Impaired Maturation of Cognitive Control in Adolescents Who Develop Major Depressive Disorder.

This study examined whether development of two forms of cognitive control (proactive and reactive) between early and midadolescence was associated with the onset of major depressive disorder (MDD) during the same period and if it prospectively predicted MDD onset between mid- and late adolescence. Adolescents (N = 165) completed 3 waves of assessments, at 12 (T1), 16 (T2), and 18 (T3) years of age. Diagnostic interviews were conducted at each time point to identify three groups of adolescents: "early MDD," those who developed MDD between early (T1) and mid- (T2) adolescence (n = 23); "late MDD," those who developed MDD between mid- (T2) and late (T3) adolescence (n = 20); and "controls," those who did not develop MDD (n = 122). A modified Stroop task was completed at T1 and T2 to examine development of proactive and reactive cognitive control. Adolescents with early MDD exhibited significant declines in reactive control, as well as a trend level decline for proactive control, during this period compared to controls. No significant differences in reactive or proactive control were identified in adolescents with late MDD compared to controls, but they did exhibit significant improvements in proactive control compared to those with early MDD. These findings suggest that normative maturation of reactive, and possibly proactive, cognitive control abilities are impaired in adolescents who develop MDD between early and midadolescence. This has implications for understanding the mechanisms underlying certain forms of behavioral dysregulation that are commonly seen in MDD.

Trait positive affect is associated with hippocampal volume and change in caudate volume across adolescence.

Trait positive affect (PA) in childhood confers both risk and resilience to psychological and behavioral difficulties in adolescence, although explanations for this association are lacking. Neurodevelopment in key areas associated with positive affect is ongoing throughout adolescence, and is likely to be related to the increased incidence of disorders of positive affect during this period of development. The aim of this study was to prospectively explore the relationship between trait indices of PA and brain development in subcortical reward regions during early to mid-adolescence in a community sample of adolescents. A total of 89 (46 male, 43 female) adolescents participated in magnetic resonance imaging assessments during both early and mid-adolescence (mean age at baseline = 12.6 years, SD = 0.45; mean follow-up period = 3.78 years, SD = 0.21) and also completed self-report measures of trait positive and negative affect (at baseline). To examine the specificity of these effects, the relation between negative affect and brain development was also examined. The degree of volume reduction in the right caudate over time was predicted by PA. Independent of time, larger hippocampal volumes were associated with higher PA, and negative affect was associated with smaller left amygdala volume. The moderating effect of negative affect on the development of the left caudate varied as a function of lifetime psychiatric history. These findings suggest that early to mid-adolescence is an important period whereby neurodevelopmental processes may underlie key phenotypes conferring both risk and resilience for emotional and behavioral difficulties later in life.

A dual-axis approach to understanding neuroendocrine development.

This introduction sets out to present a series of paper about a novel perspective regarding stress and sex hormones, or what the authors within this special issue term "coupling" of hypothalamic-pituitary-adrenal and--gonadal axes. This view postulates that these axes do not necessarily operate in opposition, but can operate together as evidenced empirically as a positive within-person association between stress hormones like cortisol or sex hormones like testosterone. A wealth of papers within the special issue demonstrate positive coupling across acute, diurnal, basal, and longitudinal timeframes and across several different types of contexts. Reviews were meant to challenge whether this was physiologically plausible. Consistently, sophisticated statistical models were utilized in order to show a template for how to model positive coupling and to ensure that coupling was a within-person phenomenon. We cautiously considered positive coupling until the consistency of observing coupling was robust enough for us to consider challenging the prevailing oppositional view of these axes. We do so to acknowledge that there are contexts, moments and stages in which the function of these axes should work together: for example when contexts are both stressful and challenging or at developmental stages (like adolescence) in which the youth must grow up despite the storm and stress of youth. We hope that by putting forward a functional dual-axis approach, the field will be able to consider when and how these axes work together.

Dual-axis hormonal covariation in adolescence and the moderating influence of prior trauma and aversive maternal parenting.

Adversity early in life can disrupt the functioning of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes and increase risk for negative health outcomes. The interplay between these axes and the environment is complex, and understanding needs to be advanced by the investigation of the multiple hormonal relationships underlying these processes. The current study examined basal hormonal associations between morning levels of cortisol, testosterone, and dehydroepiandrosterone in a cohort of adolescents (mean age 15.56 years). The moderating influence of childhood adversity was also examined, as indexed by self-reported trauma (at mean age 14.91), and observed maternal aggressive parenting (at mean age 12.41). Between-person regressions revealed significant associations between hormones that were moderated by both measures of adversity. In females, all hormones positively covaried, but also interacted with adversity, such that positive covariation was typically only present when levels of trauma and/or aggressive parenting were low. In males, hormonal associations and interactions were less evident; however, interactions were detected for cortisol-testosterone - positively covarying at high levels of aggressive parenting but negatively covarying at low levels - and DHEA-cortisol - similarly positively covarying at high levels of parental aggression. These results demonstrate associations between adrenal and gonadal hormones and the moderating role of adversity, which is likely driven by feedback mechanisms, or cross-talk, between the axes. These findings suggest that hormonal changes may be the pathway through which early life adversity alters physiology and increases health risks, but does so differentially in the sexes; however further study is necessary to establish causation.

Study protocol: imaging brain development in the Childhood to Adolescence Transition Study (iCATS).

BACKGROUND: Puberty is a critical developmental phase in physical, reproductive and socio-emotional maturation that is associated with the period of peak onset for psychopathology. Puberty also drives significant changes in brain development and function. Research to date has focused on gonadarche, driven by the hypothalamic-pituitary-gonadal axis, and yet increasing evidence suggests that the earlier pubertal stage of adrenarche, driven by the hypothalamic-pituitary-adrenal axis, may play a critical role in both brain development and increased risk for disorder. We have established a unique cohort of children who differ in their exposure to adrenarcheal hormones. This presents a unique opportunity to examine the influence of adrenarcheal timing on brain structural and functional development, and subsequent health outcomes. The primary objective of the study is to explore the hypothesis that patterns of structural and functional brain development will mediate the relationship between adrenarcheal timing and indices of affect, self-regulation, and mental health symptoms collected across time (and therefore years of development). METHODS/DESIGN: Children were recruited based upon earlier or later timing of adrenarche, from a larger cohort, with 128 children (68 female; M age 9.51 years) and one of their parents taking part. Children completed brain MRI structural and functional sequences, provided saliva samples for adrenarcheal hormones and immune biomarkers, hair for long-term cortisol levels, and completed questionnaires, anthropometric measures and an IQ test. Parents completed questionnaires reporting on child behaviour, development, health, traumatic events, and parental report of family environment and parenting style. DISCUSSION: This study, by examining the neurobiological and behavioural consequences of relatively early and late exposure to adrenarche, has the potential to significantly impact our understanding of pubertal risk processes.