Puberty and the human brain: Insights into adolescent development

Applying the Research Domain Criteria to Rodent Studies of Sex Differences in Chronic Stress Susceptibility

Women have a 2-fold increased rate of stress-associated psychiatric disorders such as depression and anxiety, but the mechanisms that underlie this increased susceptibility remain incompletely understood. Historically, female subjects were excluded from preclinical studies and clinical trials. Additionally, chronic stress paradigms used to study psychiatric pathology in animal models were developed for use in males. However, recent changes in National Institutes of Health policy encourage inclusion of female subjects, and considerable work has been performed in recent years to understand biological sex differences that may underlie differences in susceptibility to chronic stress-associated psychiatric conditions. Here, we review the utility as well as current challenges of using the framework of the National Institute of Mental Health's Research Domain Criteria as a transdiagnostic approach to study sex differences in rodent models of chronic stress including recent progress in the study of sex differences in the neurobehavioral domains of negative valence, positive valence, cognition, social processes, and arousal.

Voluntary wheel running exercise rescues behaviorally-evoked acetylcholine efflux in the medial prefrontal cortex and epigenetic changes in ChAT genes following adolescent intermittent ethanol exposure

Adolescent intermittent ethanol (AIE) exposure, which models heavy binge ethanol intake in adolescence, leads to a variety of deficits that persist into adulthood-including suppression of the cholinergic neuron phenotype within the basal forebrain. This is accompanied by a reduction in acetylcholine (ACh) tone in the medial prefrontal cortex (mPFC). Voluntary wheel running exercise (VEx) has been shown to rescue AIE-induced suppression of the cholinergic phenotype. Therefore, the goal of the current study is to determine if VEx will also rescue ACh efflux in the mPFC during spontaneous alternation, attention set shifting performance, and epigenetic silencing of the cholinergic phenotype following AIE. Male and female rats were subjected to 16 intragastric gavages of 20% ethanol or tap water on a two-day on/two-day off schedule from postnatal day (PD) 25-54, before being assigned to either VEx or stationary control groups. In Experiment 1, rats were tested on a four-arm spontaneous alternation maze with concurrent in vivo microdialysis for ACh in the mPFC. An operant attention set-shifting task was used to measure changes in cognitive and behavioral flexibility. In Experiment 2, a ChIP analysis of choline acetyltransferase (ChAT) genes was performed on basal forebrain tissue. It was found that VEx increased ACh efflux in the mPFC in both AIE and control male and female rats, as well as rescued the AIE-induced epigenetic methylation changes selectively at the Chat promoter CpG island across sexes. Overall, these data support the restorative effects of exercise on damage to the cholinergic projections to the mPFC and demonstrate the plasticity of cholinergic system for recovery after alcohol induced brain damage.

Disorders of puberty and neurodevelopment: A shared etiology?

The neuroendocrine control of puberty and reproduction is fascinatingly complex, with up- and down-regulation of key reproductive hormones during fetal, infantile, and later childhood periods that determine the correct function of the hypothalamic-pituitary-gonadal axis and the timing of puberty. Neuronal development is a vital element of these processes, and multiple conditions of disordered puberty and reproduction have their etiology in abnormal neuronal migration or function. Although there are numerous documented cases across multiple conditions wherein patients have both neurodevelopmental disorders and pubertal abnormalities, this has mostly been described ad hoc and the associations are not clearly documented. In this review, we aim to describe the overlap between these two groups of conditions and to increase awareness to ensure that puberty and reproductive function are carefully monitored in patients with neurodevelopmental conditions, and vice versa. Moreover, this commonality can be explored for clues about the disease mechanisms in these patient groups and provide new avenues for therapeutic interventions for affected individuals.

Segregation of the regional radiomics similarity network exhibited an increase from late childhood to early adolescence: A developmental investigation

Brain development is characterized by an increase in structural and functional segregation, which supports the specialization of cognitive processes within the context of network neuroscience. In this study, we investigated age-related changes in morphological segregation using individual Regional Radiomics Similarity Networks (R2SNs) constructed with a longitudinal dataset of 494 T1-weighted MR scans from 309 typically developing children aged 6.2 to 13 years at baseline. Segertation indices were defined as the relative difference in connectivity strengths within and between modules and cacluated at the global, system and local levels. Linear mixed-effect models revealed longitudinal increases in both global and system segregation indices, particularly within the limbic and dorsal attention network, and decreases within the ventral attention network. Superior performance in working memory and inhibitory control was associated with higher system-level segregation indices in default, frontoparietal, ventral attention, somatomotor and subcortical systems, and lower local segregation indices in visual network regions, regardless of age. Furthermore, gene enrichment analysis revealed correlations between age-related changes in local segregation indices and regional expression levels of genes related to developmental processes. These findings provide novel insights into typical brain developmental changes using R2SN-derived segregation indices, offering a valuable tool for understanding human brain structural and cognitive maturation.

Seeing adolescents grow from many angles using a multilevel approach: A tribute to the contributions of Dante Cicchetti to the field of developmental psychopathology

Dante Cicchetti propelled forward the field of developmental psychopathology by advancing this framework and championing new methods, including emphasizing the central role that multilevel analysis holds for explicating pathways of risk and resilience. His work continues to change the face of existing science. It has also paved the way for the formation of new projects, like the Research Domain Criteria initiative. This paper uses our laboratory's work on multilevel approaches to studying adolescent depression, non-suicidal self-injury, and suicidal thoughts and behaviors to shine a spotlight on Dr Cicchetti's contributions. In addition, we review recent developments, ongoing challenges, and promising future directions within developmental psychopathology as we endeavor to carry on the tradition of growth in the field.

Early Life Trauma, Emotion Dysregulation and Hormonal Sensitivity Across Female Reproductive Life Events

PURPOSE OF REVIEW

To explore the relationship between early life trauma, hormonal sensitivity, and psychiatric disorders across female-reproductive life events, with a focus on the neurobiological mechanisms.

RECENT FINDINGS

Childhood trauma significantly increases the risk of subsequent mood disorders during periods of intense hormonal fluctuation such as premenstrual, pregnancy, postpartum, and perimenopause. Neurobiological changes resulting from early trauma influence emotion regulation, which emerges as a key predisposing, exacerbating, and perpetuating factor to hormonal sensitivity and subsequent psychiatric symptoms. We identified altered stress response and allopregnanolone imbalance, bias in cognitive processing of emotions, neuroimage correlates and sleep disturbances as potential underlying neurobiological mechanisms. This review integrates cumulative findings supporting a theoretical framework linking early life trauma to hormonal sensitivity and mood disorders. We propose that some women might be more susceptible to such hormonal fluctuations because of emotion dysregulation following significant early life trauma.

The Dynamic Interplay Between Puberty and Structural Brain Development as a Predictor of Mental Health Difficulties in Adolescence: A Systematic Review

Puberty is a time of intense reorganization of brain structure and a high-risk period for the onset of mental health problems, with variations in pubertal timing and tempo intensifying this risk. We conducted 2 systematic reviews of articles published up to February 1, 2024, focusing on 1) the role of brain structure in the relationship between puberty and mental health, and 2) precision psychiatry research evaluating the utility of puberty in making individualized predictions of mental health outcomes in young people. The first review provides inconsistent evidence about whether and how pubertal and psychopathological processes may interact in relation to brain development. While most studies found an association between early puberty and mental health difficulties in adolescents, evidence on whether brain structure mediates this relationship is mixed. The pituitary gland was found to be associated with mental health status during this time, possibly through its central role in regulating puberty and its function in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes. In the second review, the design of studies that have explored puberty in predictive models did not allow for a quantification of its predictive power. However, when puberty was evaluated through physically observable characteristics rather than hormonal measures, it was more commonly identified as a predictor of depression, anxiety, and suicidality in adolescence. Social processes may be more relevant than biological ones to the link between puberty and mental health problems and represent an important target for educational strategies.

Neural adaptation to changes in self-voice during puberty

The human voice is a potent social signal and a distinctive marker of individual identity. As individuals go through puberty, their voices undergo acoustic changes, setting them apart from others. In this article, we propose that hormonal fluctuations in conjunction with morphological vocal tract changes during puberty establish a sensitive developmental phase that affects the monitoring of the adolescent voice and, specifically, self-other distinction. Furthermore, the protracted maturation of brain regions responsible for voice processing, coupled with the dynamically evolving social environment of adolescents, likely disrupts a clear differentiation of the self-voice from others' voices. This socioneuroendocrine framework offers a holistic understanding of voice monitoring during adolescence.

Early Emergence of Rumination has no Association with Performance on a Non-affective Inhibitory Control Task

Rumination is a vulnerability for depression and potentially linked to inhibitory control weaknesses. We aimed to replicate the association observed in adults between inhibitory control and rumination in adolescents, and to examine putative moderating roles of childhood maltreatment and perceived family cohesion in an adolescent sample at risk for depression due to familial/personal history. Ninety adolescents aged 11-17 (M = 14.6, SD = 1.8) completed self-report scales of rumination, maltreatment, and family cohesion, and performed a task assessing inhibitory control. Hierarchical regression models showed no significant relation between inhibitory control and moderator variables on rumination. However, adolescents who reported higher levels of maltreatment and who perceived lower family cohesion tended to indicate higher levels of rumination (BChilhood Maltreatment = 27.52, 95% CIs [5.63, 49.41], BFamily Cohesion = -0.40, 95% CIs [-0.65, -0.15]). These findings demonstrate an alternative understanding of factors that increase depression onset risk and recurrence in adolescents.

Social determinants of health at multiple socio-ecological levels and sleep health in adolescents: A scoping review

Heightened sleep disturbances occur in adolescence, yet existing research has predominantly focused on individual factors linked to poor sleep and a limited set of sleep outcomes, such as sleep duration and timing. This scoping review aimed to identify the multilevel social determinants of adolescent sleep health across domains, including regularity, satisfaction/quality, alertness/sleepiness, timing, efficiency/continuity, duration, and behavior. Social determinants of health (SDoH) were categorized through a socio-ecological lens, while sleep health domains were aligned with the RU-SATED and Peds B-SATED sleep health frameworks. A systematic database search resulted in 57 studies of non-clinical adolescent and young adult populations (age 10-24 y) in North America, published between 2014 and 2022. Research gaps include 1) absence of other sleep health domains other than duration which is predicated on the included studies using a limited set of sleep outcome measures rather than a more comprehensive measurement strategy that align with the multifaceted domains of sleep health, and 2) inconsistent terminology and/or absent conceptual and operational definitions of subjective sleep reports. The findings highlight the multilevel SDoH that influence adolescent sleep health, underscoring the need for more comprehensive research. Such efforts will facilitate the development of interventions focused on fostering optimal adolescent sleep health this populations.

Revisiting adolescence as a sensitive period for sociocultural processing

Waves of research and public discourse have characterized adolescence as periods of developmental risk and opportunity. Underlying this discussion is the recognition that adolescence is a period of major biological and social transition when experience may have an outsized effect on development. This article updates and expands upon prior work suggesting that adolescence may be a sensitive period for sociocultural processing specifically. By integrating evidence from developmental psychology and neuroscience, we identify how trajectories of social and neurobiological development may relate to adolescents' ability to adapt to and learn from their social environments. However, we also highlight gaps in the literature, including challenges in attributing developmental change to adolescent experiences. We discuss the importance of better understanding variability in biology (e.g., pubertal development) and cultural environments, as well as distinguishing between sensitive periods and periods of heightened sensitivity. Finally, we look toward future directions and translational implications of this research.

Effects of Congenital Adrenal Hyperplasia (CAH) and Biological Sex on Brain Size

Congenital Adrenal Hyperplasia (CAH) has been reported to involve structural alterations in some brain regions. However, it remains to be established whether there is also an impact on the size of the brain as a whole. Here, we compiled the largest CAH sample to date (n = 53), matched pair-wise to a control group (n = 53) on sex, age, and verbal intelligence. Using T1-weighted brain scans, we calculated intracranial volume (ICV) as well as total brain volume (TBV), which are both common estimates for brain size. The statistical analysis was performed using a general linear model assessing the effects of CAH (CAH vs. controls), sex (women vs. men), and any CAH-by-sex interaction. The outcomes were comparable for ICV and TBV, i.e., there was no significant main effect of CAH and no significant CAH-by-sex interaction. However, there was a significant main effect of sex, with larger ICVs and TBVs in men than in women. Our findings contribute to an understudied field of research exploring brain anatomy in CAH. In contrast to some existing studies suggesting a smaller brain size in CAH, we did not observe such an effect. In other words, ICV and TBV in women and men with CAH did not differ significantly from those in controls. Notwithstanding, we observed the well-known sex difference in brain size (12.69% for ICV and 12.50% for TBV), with larger volumes in men than in women, which is in agreement with the existing literature.

Associations Among Birth Weight, Adrenarche, Brain Morphometry, and Cognitive Function in Preterm Children Ages 9 to 11 Years

BACKGROUND

Preterm infants with low birth weight are at heightened risk of developmental sequelae, including neurological and cognitive dysfunction that can persist into adolescence or adulthood. In addition, preterm birth and low birth weight can provoke changes in endocrine and metabolic processes that likely impact brain health throughout development. However, few studies have examined associations among birth weight, pubertal endocrine processes, and long-term neurological and cognitive development.

METHODS

We investigated the associations between birth weight and brain morphometry, cognitive function, and onset of adrenarche assessed 9 to 11 years later in 3571 preterm and full-term children using the ABCD (Adolescent Brain Cognitive Development) Study dataset.

RESULTS

The preterm children showed lower birth weight and early adrenarche, as expected. Birth weight was positively associated with cognitive function (all Cohen's d > 0.154, p < .005), global brain volumes (all Cohen's d > 0.170, p < .008), and regional volumes in frontal, temporal, and parietal cortices in preterm and full-term children (all Cohen's d > 0.170, p < .0007); cortical volume in the lateral orbitofrontal cortex partially mediated the effect of low birth weight on cognitive function in preterm children. In addition, adrenal score and cortical volume in the lateral orbitofrontal cortex mediated the associations between birth weight and cognitive function only in preterm children.

CONCLUSIONS

These findings highlight the impact of low birth weight on long-term brain structural and cognitive function development and show important associations with early onset of adrenarche during the puberty. This understanding may help with prevention and treatment.

Sex-specific associations of a ferroalloy metal mixture with motor function in Italian adolescents

Background

Motor function is critical for children's health, yet remains an understudied neurodevelopmental domain. Exposure to metals has been linked with motor function, but no study has examined the joint effects of metal mixtures.

Methods

We evaluated cross-sectional associations between a metal mixture and motor function among 569 adolescents (10-14 years old) living near the ferroalloy industry. Concentrations of blood lead, hair manganese, hair copper, and hair chromium were quantified using inductively coupled plasma mass spectrometry. Neuropsychologists administered multiple fine motor function assessments: pursuit aiming, finger tapping, visual reaction time (VRT), and subtests from the Luria Nebraska battery. We estimated associations between motor function and the metal mixture using quantile-based g-computation and multivariable linear regression, adjusting for child age, sex, and socioeconomic status. We explored sex-specific associations in stratified models.

Results

Associations between the metal mixture and motor function were mostly null but were modified by sex. We observed a beneficial association among females: a quartile increase in all metals in the mixture was associated with a 2.6% faster average response time on the VRT (95% confidence interval [CI] = -4.7%, -0.5%), driven by Cu and Cr. In contrast, this association was adverse among males (ß = 1.5% slower response time [95% CI = -0.7%, 3.9%]), driven by Cu and Mn.

Conclusions

Results suggest that males may be more susceptible to the adverse effects of metal exposure on motor function during adolescence than females. Future studies, particularly prospective study designs, are warranted to further understand the associations of metal mixtures with motor function.

MRI signatures of cortical microstructure in human development align with oligodendrocyte cell-type expression

Neuroanatomical changes to the cortex during adolescence have been well documented using MRI, revealing ongoing cortical thinning and volume loss with age. However, the underlying cellular mechanisms remain elusive with conventional neuroimaging. Recent advances in MRI hardware and new biophysical models of tissue informed by diffusion MRI data hold promise for identifying the cellular changes driving these morphological observations. This study used ultra-strong gradient MRI to obtain high-resolution, in vivo estimates of cortical neurite and soma microstructure in sample of typically developing children and adolescents. Cortical neurite signal fraction, attributed to neuronal and glial processes, increased with age (mean R2 fneurite=.53, p<3.3e-11, 11.91% increase over age), while apparent soma radius decreased (mean R2 Rsoma=.48, p<4.4e-10, 1% decrease over age) across domain-specific networks. To complement these findings, developmental patterns of cortical gene expression in two independent post-mortem databases were analysed. This revealed increased expression of genes expressed in oligodendrocytes, and excitatory neurons, alongside a relative decrease in expression of genes expressed in astrocyte, microglia and endothelial cell-types. Age-related genes were significantly enriched in cortical oligodendrocytes, oligodendrocyte progenitors and Layer 5-6 neurons (pFDR<.001) and prominently expressed in adolescence and young adulthood. The spatial and temporal alignment of oligodendrocyte cell-type gene expression with neurite and soma microstructural changes suggest that ongoing cortical myelination processes contribute to adolescent cortical development. These findings highlight the role of intra-cortical myelination in cortical maturation during adolescence and into adulthood.

Breathing life into social emotional learning programs: A Bio-Psycho-Social approach to risk reduction and positive youth development

INTRODUCTION

Over one-third of US adolescents engage in health risk and problem behaviors. Additionally, significant percentages of problem-free youth aren't flourishing. Left unaddressed, the lifetime mental/physical health and financial burdens may be substantial. Social-Emotional Learning (SEL) and Positive Youth Development (PYD) programs have proliferated to address the drivers of adaptive versus risk behaviors. Research suggests SEL/PYD program outcomes can be improved by adding techniques that physiologically induce calmness, yet few studies exist.

METHODS

This randomized controlled trial of 79 urban eighth-graders examined a standardized bio-psycho-social program, SKY Schools, which incorporates a physiologically calming component: controlled yogic breathing.

RESULTS

Repeated-measures ANOVAs demonstrated that compared to controls, SKY graduates exhibited significant improvements in emotion regulation, planning and concentration, and distractibility. After 3 months, significant improvements were evidenced in emotion regulation, planning and concentration, identity formation, and aggressive normative beliefs.

CONCLUSION

SEL/PYD programs may benefit by incorporating biologically-calming techniques to enhance well-being and prevent risk/problem behaviors.

Examining neural responses to anticipating or receiving monetary rewards and the development of binge eating in youth. A registered report using data from the Adolescent Brain Cognitive Development (ABCD) study

Binge eating is characterized as eating a large amount of food and feeling a loss of control while eating. However, the neurobiological mechanisms associated with the onset and maintenance of binge eating are largely unknown. Recent neuroimaging work has suggested that increased responsivity within reward regions of the brain to the anticipation or receipt of rewards is related to binge eating; however, limited longitudinal data has precluded understanding of the role of reward responsivity in the development of binge eating. The current study used data from the Adolescent Brain and Cognitive Development® (ABCD) longitudinal study dataset to assess whether heightened neural responses to different phases of reward processing (reward anticipation and receipt) (1) differentiated individuals with binge eating from matched controls, and (2) predicted the onset of binge eating in an "at risk" sample. Consistent with hypotheses, heightened neural responsivity in the right caudate and bilateral VS during reward anticipation differentiated youth with and without binge eating. Moreover, greater VS response to reward anticipation predicted binge eating two years later. Neural responses to reward receipt also were consistent with hypotheses, such that heightened VS and OFC responses differentiated youth with and without binge eating and predicted the presence of binge eating two years later. Findings from the current study suggest that hypersensitivity to rewards may contribute to the development of binge eating during early adolescence.

Alcohol Consumption During Adolescence Alters the Cognitive Function in Adult Male Mice by Persistently Increasing Levels of DUSP6

Binge alcohol drinking during adolescence has long-term effects on the adult brain that alter brain structure and behaviors, but the underlying mechanisms remain poorly understood. Extracellular signal-regulated kinase (ERK) is involved in the synaptic plasticity and pathological brain injury by regulating the expression of cyclic adenosine monophosphate response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF). Dual-specificity phosphatase 6 (DUSP6) is a critical effector that dephosphorylates ERK1/2 to control the basal tone, amplitude, and duration of ERK signaling. To explore DUSP6 as a regulator of ERK signaling in the mPFC and its impact on long-term effects of alcohol, a male mouse model of adolescent intermittent alcohol (AIA) exposure was established. Behavioral experiments showed that AIA did not affect anxiety-like behavior or sociability in adulthood, but significantly damaged new object recognition and social recognition memory. Molecular studies further found that AIA reduced the levels of pERK-pCREB-BDNF-PSD95/NR2A involved in synaptic plasticity, while DUSP6 was significantly increased. Intra-mPFC infusion of AAV-DUSP6-shRNA restored the dendritic spine density and postsynaptic density thickness by reversing the level of p-ERK and its downstream molecular expression, and ultimately repaired adult cognitive impairment caused by chronic alcohol exposure during adolescence. These findings indicate that AIA exposure inhibits ERK-CREB-BDNF-PSD95/NR2A by increasing DUSP6 in the mPFC in adulthood that may be associated with long-lasting cognitive deficits.

Adolescent neurocognitive development and decision-making abilities regarding gender-affirming care

Recently, politicians and legislative bodies have cited neurodevelopmental literature to argue that brain immaturity undermines decision-making regarding gender-affirming care (GAC) in youth. Here, we review this literature as it applies to adolescents' ability to make decisions regarding GAC. The research shows that while adolescence is a time of peak risk-taking behavior that may lead to impulsive decisions, neurocognitive systems supporting adult-level decisions are available given deliberative processes that minimize influence of short-term rewards and peers. Since GAC decisions occur over an extended period and with support from adult caregivers and clinicians, adolescents can engage adult-level decision-making in this context. We also weigh the benefits of providing GAC access during adolescence and consider the significant costs of blocking or delaying GAC. Transgender and non-binary (TNB) adolescents face significant mental health challenges, many of which are mitigated by GAC access. Further, initiating the GAC process during adolescence, which we define as beginning at pubertal onset, leads to better long-term mental health outcomes than waiting until adulthood. Taken together, existing research indicates that many adolescents can make informed decisions regarding gender-affirming care, and that this care is critical for the well-being of TNB youth. We highlight relevant considerations for policy makers, researchers, and clinicians.

Life satisfaction among Spanish children and adolescents participating in Physical Education

Life satisfaction has been determined as a cognitive indicator of subjective wellbeing, a term that acquires vital relevance during adolescence as a protective factor against numerous psychological, mental and social disorders. Therefore, the objectives of this study are: (1) to evaluate differences in life satisfaction as a function of gender and school environment in Spanish children and adolescents; and (2) examine the possible associations between life satisfaction and age and/or body mass index (BMI) of the student body. For this purpose, a cross-sectional study was carried out with 723 students (aged 6 to 18 years) in which the "Satisfaction with life Scale" was applied, consisting of 5 items that measure self-perception of life satisfaction. Nonparametric statistics (Mann-Whitney U test) were used to explore differences in scores according to sex and school environment, in addition to Spearman's Rho test to identify associations between scale scores and students' age and BMI. Significant differences were obtained in terms of sex in favor of the male gender, and between the two environments of the centers in favor of the rural ones. In addition, the two variables explored (age and BMI) showed significant inverse associations with life satisfaction levels. Therefore, educational interventions and policies must take this information into account to design and develop actions aimed at improving this cognitive factor.

The impact of menarche on hippocampal mechanisms of severity of psychotic-like experiences in the ABCD study

Accumulating evidence suggests that estrogens play an important modulatory role in the pathogenesis of psychosis. Estrogens come online within a dynamic developmental context of emerging psychopathology and neurodevelopment. As a result, estradiol (the primary form of estrogen) may influence psychosis lability directly or indirectly through its neurodevelopmental influence on estrogens-sensitive areas like the hippocampus. Understanding this influence may provide novel insight into mechanisms of psychosis lability. This study included baseline and year 2 timepoints from 4422 female participants from the Adolescent Brain Cognitive Development (ABCD) study (age 8-13), who varied in estradiol availability (pre-menarche, post-menarche, pre- and post-menarche timepoints). Estradiol availability was related to psychotic-like experiences (PLE) severity both directly and as an interactive effect with hippocampal connectivity using menarche status (pre/post) in a multilevel model. PLE severity was highest in individuals with early menarche emphasizing the importance of the developmental timing. Although PLE severity decreased over time in the sample, it stayed clinically-relevant over 2 years. Lower hippocampal connectivity was related to elevated PLE severity. This effect was moderated by estradiol; before the availability of estradiol (pre-menarche), lower hippocampal connectivity significantly contributed to the PLE severity, but when estradiol was available (post-menarche) hippocampal dysconnectivity did not account for PLE severity. This moderation suggests that the estrodiol's influence on hippocampal plasticity also reduced the mechanistic role of the hippocampus on PLE severity. Further, the lack of a significant direct reduction of PLE severity post-menarche, may suggest an increased role for other interacting psychosis lability factors during this critical developmental period.

Associations between somatomotor-putamen resting state connectivity and obsessive-compulsive symptoms vary as a function of stress during early adolescence: Data from the ABCD study

Obsessive-compulsive symptoms (OCS) are relatively common during adolescence although most individuals do not meet diagnostic criteria for obsessive-compulsive disorder (OCD). Nonetheless, OCS during adolescence are associated with comorbid psychopathologies and behavioral problems. Heightened levels of environmental stress and greater functional connectivity between the somatomotor network and putamen have been previously associated with elevated OCS in OCD patients relative to healthy controls. However, the interaction of these factors within the same sample of individuals has been understudied. This study examined somatomotor-putamen resting state connectivity, stress, and their interaction on OCS in adolescents from 9-12 years of age. Participants (n = 6386) were drawn from the ABCD Study 4.0 release. Multilevel modeling was used to account for nesting in the data and to assess changes in OCS in this age range. Stress moderated the association between somatomotor-putamen connectivity and OCS (β = 0.35, S.E. = 0.13, p = 0.006). Participants who reported more stress than their average and had greater somatomotor-left putamen connectivity reported more OCS, whereas participants who reported less stress than their average and had greater somatomotor-left putamen connectivity reported less OCS. These data suggest that stress differentially affects the direction of association between somatomotor-putamen connectivity and OCS. Individual differences in the experience or perception of stress may contribute to more OCS in adolescents with greater somatomotor-putamen connectivity.

Brain network connectivity during peer evaluation in adolescent females: Associations with age, pubertal hormones, timing, and status

Despite copious data linking brain function with changes to social behavior and mental health, little is known about how puberty relates to brain functioning. We investigated the specificity of brain network connectivity associations with pubertal indices and age to inform neurodevelopmental models of adolescence. We examined how brain network connectivity during a peer evaluation fMRI task related to pubertal hormones (dehydroepiandrosterone and testosterone), pubertal timing and status, and age. Participants were 99 adolescents assigned female at birth aged 9-15 (M = 12.38, SD = 1.81) enriched for the presence of internalizing symptoms. Multivariate analysis revealed that within Salience, between Frontoparietal - Reward and Cinguloopercular - Reward network connectivity were associated with all measures of pubertal development and age. Specifically, Salience connectivity linked with age, pubertal hormones, and status, but not timing. In contrast, Frontoparietal - Reward connectivity was only associated with hormones. Finally, Cinguloopercular - Reward connectivity related to age and pubertal status, but not hormones or timing. These results provide evidence that the salience processing underlying peer evaluation is jointly influenced by various indices of puberty and age, while coordination between cognitive control and reward circuitry is related to pubertal hormones, pubertal status, and age in unique ways.

Annual Research Review: Puberty and the development of anhedonia - considering childhood adversity and inflammation

Anhedonia, or diminished pleasure and motivation, is a symptom of severe mental illness (e.g., depressive disorder, bipolar disorder, schizophrenia) that emerges during adolescence. Anhedonia is a pernicious symptom that is related to social impairments, treatment resistance, and suicide. As the mechanisms of anhedonia are postulated to include the frontostriatal circuitry and the dopamine neuromodulatory system, the development and plasticity of these systems during the vulnerable period of adolescence, as well as their sensitivity to pubertal hormones, suggest that pubertal maturation could play a role in the development of anhedonia. This review takes a developmental perspective, considering the possibility that anhedonia emerges in the context of pubertal maturation and adolescent development, with childhood adversity and chronic inflammation influencing neural reward systems to accelerate anhedonia's progression. Here, we review the relevant extant literature on the components of this model and suggest directions for future research.

Sex and pubertal variation in reward-related behavior and neural activation in early adolescents

This study aimed to characterize the role of sex and pubertal markers in reward motivation behavior and neural processing in early adolescence. We used baseline and two-year follow-up data from the Adolescent Brain and Cognitive DevelopmentSM study (15844 observations; 52% from boys; age 9-13). Pubertal development was measured with parent-reported Pubertal Development Scale, and DHEA, testosterone, and estradiol levels. Reward motivation behavior and neural processing at anticipation and feedback stages were assessed with the Monetary Incentive Delay task. Boys had higher reward motivation than girls, demonstrating greater accuracy difference between reward and neutral trials and higher task earnings. Girls had lower neural activation during reward feedback than boys in the nucleus accumbens, caudate, rostral anterior cingulate, medial orbitofrontal cortex, superior frontal gyrus and posterior cingulate. Pubertal stage and testosterone levels were positively associated with reward motivation behavior, although these associations changed when controlling for age. There were no significant associations between pubertal development and neural activation during reward anticipation and feedback. Sex differences in reward-related processing exist in early adolescence, signaling the need to understand their impact on typical and atypical functioning as it unfolds into adulthood.

Menarche, pubertal timing and the brain: female-specific patterns of brain maturation beyond age-related development

BACKGROUND

Puberty depicts a period of profound and multifactorial changes ranging from social to biological factors. While brain development in youths has been studied mostly from an age perspective, recent evidence suggests that pubertal measures may be more sensitive to study adolescent neurodevelopment, however, studies on pubertal timing in relation to brain development are still scarce.

METHODS

We investigated if pre- vs. post-menarche status can be classified using machine learning on cortical and subcortical structural magnetic resonance imaging (MRI) data from strictly age-matched adolescent females from the Adolescent Brain Cognitive Development (ABCD) cohort. For comparison of the identified menarche-related patterns to age-related patterns of neurodevelopment, we trained a brain age prediction model on data from the Philadelphia Neurodevelopmental Cohort and applied it to the same ABCD data, yielding differences between predicted and chronological age referred to as brain age gaps. We tested the sensitivity of both these frameworks to measures of pubertal maturation, specifically age at menarche and puberty status.

RESULTS

The machine learning model achieved moderate but statistically significant accuracy in the menarche classification task, yielding for each subject a class probability ranging from 0 (pre-) to 1 (post- menarche). Comparison to brain age predictions revealed shared and distinct patterns of neurodevelopment captured by both approaches. Continuous menarche class probabilities were positively associated with brain age gaps, but only the menarche class probabilities-not the brain age gaps-were associated with age at menarche.

CONCLUSIONS

This study demonstrates the use of a machine learning model to classify menarche status from structural MRI data while accounting for age-related neurodevelopment. Given its sensitivity towards measures of puberty timing, our work suggests that menarche class probabilities may be developed toward an objective brain-based marker of pubertal development.

Neuroanatomical variability associated with early substance use initiation: Results from the ABCD Study

The extent to which neuroanatomical variability associated with substance involvement reflects pre-existing risk and/or consequences of substance exposure remains poorly understood. In the Adolescent Brain Cognitive DevelopmentSM (ABCD®) Study, we identify associations between global and regional differences in brain structure and early substance use initiation (i.e., occurring <15 years of age; nsanalytic=6,556-9,804), with evidence that associations precede initiation. Neurodevelopmental variability in brain structure may confer risk for substance involvement.

Remembering the null hypothesis when searching for brain sex differences

Human brain sex differences have fascinated scholars for centuries and become a key focus of neuroscientists since the dawn of MRI. We recently published a major review in Neuroscience and Biobehavioral Reviews showing that most male-female brain differences in humans are small and few have been reliably replicated. Although widely cited, this work was the target of a critical Commentary by DeCasien et al. (Biol Sex Differ 13:43, 2022). In this response, I update our findings and confirm the small effect sizes and pronounced scatter across recent large neuroimaging studies of human sex/gender difference. Based on the sum of data, neuroscientists would be well-advised to take the null hypothesis seriously: that men and women's brains are fundamentally similar, or "monomorphic". This perspective has important implications for how we study the genesis of behavioral and neuropsychiatric gender disparities.

Using the health beliefs model to implement mobile puberty health education in Iranian adolescent boys: a randomized controlled trial

Introduction

Given boys' low health knowledge and their unhealthy behavior during puberty, which can cause many physical, mental, and psychological problems, it is important to prevent these complications. This study was therefore aimed to determine the efficacy of a mobile health educational intervention based on the Health Beliefs Model (HBM) on Iranian adolescent boys.

Materials and methods

This randomized controlled trial involved junior high school boys (n = 148) in Iran studying during the 2020-2021 school year. Educational content concerning healthy behaviors during puberty (e.g., the importance of bathing) was developed based on HBM and sent to the intervention group via mobile phone. HBM addresses multiple factors (e.g., perceived disease risk) that explain health behaviors. The intervention was delivered in five sessions over four weeks using real-time Internet communication and texting. The control group did not receive any intervention. One school was randomly selected from each of the four districts of the study site. The schools were then randomized into intervention and control groups. The boys were then randomly selected from each school to participate in the study. Data collected at baseline and 2-month follow-up assessments included demographic information, health knowledge (e.g., physical changes during puberty), health behaviors (e.g., bathing), and HBM constructs (e.g., self-efficacy to perform healthy behaviors). Data analysis was done using the chi-square, independent and paired t-tests, and analysis of covariance (ANCOVA).

Results

The two groups did not differ in terms of demographic characteristics. Before the intervention, the two groups were slightly different in terms of knowledge, health behavior, and HBM constructs. Following the intervention, the scores of the intervention group improved significantly (p < 0.05). After adjusting for pre-intervention knowledge, HBM, and health behavior scores, the intervention group remained superior to the control group in terms of improvement of knowledge, HBM constructs, and healthy behaviors (p < 0.05). Effect sizes ranged from medium to large (0.25-0.86).

Conclusion

Mobile phone education based on the HBM is efficacious in encouraging healthy behavior in boys during puberty. Organizations interested in encouraging healthy behaviors in boys should consider the use of such a program.

Transcutaneous auricular vagus nerve stimulation ameliorates adolescent depressive- and anxiety-like behaviors via hippocampus glycolysis and inflammation response

BACKGROUND

Transcutaneous auricular vagus nerve stimulation (taVNS) is a crucial neuromodulation therapy for depression, yet its molecular mechanism remains unclear. Here, we aim to unveil the underlying mechanisms of antidepression by systematically evaluating the change of gene expression in different brain regions (i.e., hippocampus, anterior cingulate cortex, and medial prefrontal cortex).

METHODS

The adolescent depression rat model was established by chronic unpredictable mild stress (CUMS), followed by the taVNS treatment for 3 weeks. The open field test (OFT), forced swimming test (FST), elevated plus maze test (EPM), and new object recognition (NOR) test were used to evaluate depressive- and anxiety-like behaviors. Gene expression analysis of three brain regions was conducted by RNA sequencing (RNA-seq) and further bioinformatics methods.

RESULTS

The depressive- and anxiety-like behaviors in CUMS-exposed rats were manifested by decreased spontaneous locomotor activity of OFT, increased immobility time of FST, increased entries and time in the closed arms of EPM, and decreased new object index of NOR. Furthermore, CUMS exposure also led to alterations in gene expression within the hippocampus (HIP), anterior cingulate cortex (ACC), and medial prefrontal cortex (mPFC), suggesting a potential link between adolescent stress and pathological changes within these brain regions. TaVNS could significantly ameliorate depressive- and anxiety-like behaviors. Its effects on these three brain regions were found related to regulation of the metabolism, and there were some brain region-specific findings. Compared with ACC and mPFC, taVNS has a more concrete effect on HIP by regulating the inflammation response and glycolysis.

CONCLUSION

taVNS is capable of ameliorating adolescent depressive- and anxiety-like behaviors by regulating plenty of genes in the three brain regions. Suppressed level of inflammatory response and enhanced glycolysis manifests the dominant role of taVNS in HIP, which provides a theoretical foundation and data support for the molecular mechanism of antidepression by taVNS.

Global, regional, and national burden of depressive disorders among young people aged 10-24 years, 2010-2019

OBJECTIVE

To describe the latest disease burden, temporal trends, and risk factors of depressive disorders among young people.

METHODS

Data from the Global Burden of Disease Study 2019 was utilized to analyze depressive disorders among individuals aged 10-24 years. The study focused on describing the incidence, prevalence, disability-adjusted life years (DALYs), and their attributable risk factors across 204 countries and territories from 2010 to 2019. The estimated annual percentage change (EAPC) was calculated to quantify the temporal trends.

RESULTS

Globally, the incidence, prevalence, and DALYs rate of depressive disorders per 100 000 young people increased from 3003.01, 2445.69, and 448.61 in 2010 to 3035.26, 2470.67, and 452.58 in 2019, indicating a slight upward trend (EAPC = 0.11 for incidence and prevalence; EAPC = 0.09 for DALYs rate). Notably, the percentage of DALYs of depressive disorders among young people increased substantially from 3.24% in 2010 to 3.66% in 2019, an increase of 13.06% (EAPC = 1.26, 95%CI: 1.08-1.44), and the burden of depressive disorders among young people rose from fouth to second in females, and from tenth to fifth in males. Social demographic index (SDI) and other indicators were positively correlated with the percentage of DALYs of depressive disorder and negatively correlated with the EAPC of DALYs.

CONCLUSION

The global burden of depressive disorders among young people is on the rise. The regional differences in depressive disorders among young people suggest the need for enhanced screening efforts in low-SDI areas, along with the adoption of more effective prevention and control measures.

Divergent Evolutionary Rates of Primate Brain Regions as Revealed by Genomics and Transcriptomics

Although the primate brain contains numerous functionally distinct structures that have experienced diverse genetic changes during the course of evolution and development, these changes remain to be explored in detail. Here we utilize two classic metrics from evolutionary biology, the evolutionary rate index (ERI) and the transcriptome age index (TAI), to investigate the evolutionary alterations that have occurred in each area and developmental stage of the primate brain. We observed a higher evolutionary rate for those genes expressed in the non-cortical areas during primate evolution, particularly in human, with the highest rate of evolution being exhibited at brain developmental stages between late infancy and early childhood. Further, the transcriptome age of the non-cortical areas was lower than that of the cerebral cortex, with the youngest age apparent at brain developmental stages between late infancy and early childhood. Our exploration of the evolutionary patterns manifest in each brain area and developmental stage provides important reference points for further research into primate brain evolution.

Maturational trend of daytime sleep propensity in adolescents

STUDY OBJECTIVES

The teenage increase in sleepiness is not simply a response to decreasing nighttime sleep duration. Daytime sleepiness increases across adolescence even when prior sleep duration is held constant. Here we determine the maturational trend in daytime sleep propensity assessed with the multiple sleep latency test (MSLT) and assess the trend's relation to pubertal maturation and changes in the sleep electroencephalogram. We also evaluate whether the relation of daytime sleep propensity to prior sleep duration changes between ages 10 and 23 years.

METHODS

Participants (n = 159) entered the study between ages 9.8 and 22.8 years and were studied annually for up to 3 years. Annually, participants kept each of three sleep schedules in their homes: 7, 8.5, and 10 hours in bed for 4 consecutive nights with polysomnography on nights 2 and 4. MSLT-measured daytime sleep propensity was assessed in the laboratory on the day following the fourth night.

RESULTS

A two-part linear spline model described the maturation of daytime sleep propensity. MSLT sleep likelihood increased steeply until age 14.3 years, after which it did not change significantly. The maturational trend was strongly associated with the adolescent decline in slow-wave (delta, 1-4 Hz) EEG power during NREM sleep and with pubertal maturation assessed with Tanner stage measurement of breast/genital development. The effect of prior sleep duration on sleep likelihood decreased with age.

CONCLUSIONS

Adolescent brain changes related to pubertal maturation and those reflected in the delta decline contribute to the adolescent increase in daytime sleep propensity.

The influence of socioenvironmental risk factors on risk-taking behaviors among Bahamian adolescents: a structural equation modeling analysis

Background

Adolescents' risk-taking behaviors can have profound impacts on their future health. Few studies have established a relationship between multiple social environmental factors and adolescent risk behaviors. We used structural equation modeling to examine the role of parental monitoring and environmental risks on adolescents' behavioral intentions and risk behaviors.

Methods

Data were collected through the baseline survey of a national implementation project among 2205 Grade 6 students in 24 government schools in The Bahamas in 2019. Structural equation modeling examined relations among parental monitoring, environmental risk factors, behavioral intentions, and risk behaviors.

Results

Students had engaged in various delinquent, substance use, and sexual risks. In the structural equation model, parental monitoring demonstrated direct negative (protective) effects on behavioral intentions and risk behaviors, whereas environmental risk factors had a direct positive effect on adolescent behavioral intentions and risk behaviors. The model had an R2 value of 0.57 for adolescent risk behaviors.

Conclusion

Parental monitoring and environmental risk factors had strong influences on risk-taking behaviors of early adolescents. Future adolescent health behavior interventions should consider offering additional prevention resources to early adolescents who are exposed to multiple environmental risk factors.

Association between meeting the 24-h movement guidelines and psychosocial health in children: A cross-sectional study

OBJECTIVE

Emerging evidence suggests that meeting the 24-h movement guidelines is associated with optimal mental health. However, there remains some uncertainty regarding this association in children. Therefore, this study aimed to examine the association between meeting the 24-h movement guidelines and psychosocial health in children.

METHODS

A cross-sectional study design was employed to investigate 2005 children aged 9-12 years from four districts of Shanghai, China. The 24-h movement behaviours were assessed using selected items from the Health Behaviour in School-aged Children (HBSC) survey questionnaire. Children's self-rated psychosocial health was evaluated using the Strengths or Difficulties Questionnaire (SDQ). Generalised Linear Models with the ordinal logistic module were employed to analyse the association between meeting the 24-h movement guidelines and psychosocial health.

RESULTS

The overall prevalence of meeting all three 24-h movement recommendations was 10.2%. Among children, 7.9% of them exhibited abnormal total difficulties, with a notable difference between sex (boys: 11.2%, girls: 7.0%, p = 0.001). Meeting all three 24-h movement behaviour recommendations was associated with reduced total difficulties, emotional symptoms, conduct problems, hyperactivity and peer problems. Furthermore, a dose-response association was observed, indicating that meeting a greater number of 24-h movement behaviour recommendations was associated with enhanced psychosocial health, particularly in boys.

CONCLUSION

The findings of this study highlight the positive association between meeting the 24-h movement guidelines and psychosocial health in children. Notably, meeting more of these recommendations was associated with a lower likelihood of experiencing psychosocial problems, with greater benefits observed in boys compared with girls.

Relationship between sleep problems and headaches among adolescents: Pelotas 2004 Birth cohort

Objective

To investigate the cross-sectional association between sleep problems (the exposure) and headaches (the outcome) among 15-year-olds from the Pelotas 2004 Birth Cohort, a population-based study in the south of Brazil.

Method

The occurrence of headaches was obtained through the question: "Do you usually suffer headaches?" and the ICHD-3 criteria were used to classify as: tension-type headache, headache with characteristics of migraine with or without aura, or other. Regarding sleep, the weekly frequency in the last month of insomnia and bad dreams/nightmares, and self-reported sleep quality were investigated. Unadjusted and adjusted prevalence ratios (PR) with 95% confidence intervals were calculated using Poisson regression with robust variance.

Results

A total of 1916 adolescents were analyzed. The prevalence of headaches was 51.6% (69.0% in females and 34.8% in males): 31.8% (39.7% vs. 24.1%) reported tension-type headache; 14.7% (21.9% vs. 7.8%), headaches with characteristics of migraines without aura; 3.6%, headaches with characteristics of migraines with aura; and 1.5% (5.1% vs. 2.3%), other types. Adolescents with insomnia ≥3 times/week presented higher probability of headaches (PR = 1.54; 95%CI 1.23-1.93), compared with those with no problems falling asleep or maintaining sleep. Among those who classified their sleep as poor/very poor, the probability of headaches was 33% higher (PR = 1.33; 95%CI 1.13-1.57) than among those who classified their sleep as very good.

Conclusions

Headaches were highly prevalent among the adolescents and were related to sleep problems even after allowing for several confounders.

Adipose tissue homeostasis orchestrates the oxidative, energetic, metabolic and endocrine disruption induced by binge drinking in adolescent rats

Binge drinking (BD) is the most common alcohol consumption model for adolescents, and has recently been related to the generation of high oxidation and insulin resistance (IR). White adipose tissue (WAT) is a target organ for insulin action that regulates whole-body metabolism by secreting adipokines. The present study aimed to analyse the oxidative, inflammatory, energetic and endocrine profile in the WAT of BD-exposed adolescent rats, to obtain an integrative view of insulin secretion and WAT in IR progression. Two groups of male adolescent rats were used: control (n = 8) and BD (n = 8). An intermittent i.p. BD model (20% v/v) was used during 3 consecutive weeks. BD exposure led to a pancreatic oxidative imbalance, which was joint to high insulin secretion by augmenting deacetylase sirtuin-1 (SIRT-1) pancreatic expression and serum adipsin levels. However, BD rats had hyperglycaemia and high homeostasis model assessment of insulin resistance value (HOMA-IR). BD exposure in WAT increased lipid oxidation, as well as decreased insulin receptor substrate 1 (IRS-1) and AKT expression, sterol regulatory element-binding protein 1 (SREBP1), forkhead box O3A (FOXO3a) and peroxisome proliferator-activated receptor γ (PPARγ), and adipocyte size. BD also affected the expression of proteins related to energy balance, such as SIRT-1 and AMP activated protein kinase (AMPK), affecting the adipokine secretion profile (increasing resistin/adiponectin ratio). BD altered the entire serum lipid profile, increasing the concentration of free fatty acids. In conclusion, BD led to an oxidative imbalance and IR process in WAT, which modified the energy balance in this tissue, decreasing the WAT lipogenic/lipolytic ratio, affecting adipokine secretion and the systemic lipid profile, and contributing to the progression of IR. Therefore, WAT is key in the generation of metabolic and endocrine disruption after BD exposure during adolescence in rats. KEY POINTS: Adolescent rat binge drinking (BD) exposure leads to hepatic and systemic oxidative stress (OS) via reactive oxygen species generation, causing hepatic insulin resistance (IR) and altered energy metabolism. In the present study, BD exposure in adolescent rats induces OS in the pancreas, with increased insulin secretion despite hyperglycaemia, indicating a role for IR in white adipose tissue (WAT) homeostasis. In WAT, BD produces IR and an oxidative and energetic imbalance, triggering an intense lipolysis where the serum lipid profile is altered and free fatty acids are increased, consistent with liver lipid accumulation and steatosis. BD exposure heightens inflammation in WAT, elevating pro-inflammatory and reducing anti-inflammatory adipokines, favouring cardiovascular damage. This research provides a comprehensive view of how adolescent BD in rats impacts liver, WAT and pancreas homeostasis, posing a risk for future cardiometabolic complications in adulthood.

Corticolimbic connectivity mediates the relationship between pubertal timing and mental health problems

BACKGROUND

Undergoing puberty ahead of peers ('earlier pubertal timing') is an important risk factor for mental health problems during early adolescence. The current study examined pathways between pubertal timing and mental health via connectivity of neural systems implicated in emotional reactivity and regulation (specifically corticolimbic connections) in 9- to 14-year-olds.

METHOD

Research questions were examined in the Adolescent Brain Cognitive Development (ABCD) Study, a large population representative sample in the United States. Linear mixed models examined associations between pubertal timing and resting-state corticolimbic connectivity. Significant connections were examined as potential mediators of the relationship between pubertal timing and mental health (withdrawn depressed and rule-breaking) problems. Exploratory analyses interrogated whether the family environment moderated neural risk patterns in those undergoing puberty earlier than their peers.

RESULTS

Earlier pubertal timing was related to decreased connectivity between limbic structures (bilateral amygdala and right hippocampus) and the cingulo-opercular network, left amygdala and somatomotor (mouth) network, as well as between the left hippocampus and ventral attention network and visual network. Corticolimbic connections also mediated the relationship between earlier pubertal timing and increased withdrawn depressed problems (but not rule-breaking problems). Finally, parental acceptance buffered against connectivity patterns that were implicated in withdrawn depressed problems in those undergoing puberty earlier than their peers.

CONCLUSION

Findings highlight the role of decreased corticolimbic connectivity in mediating pathways between earlier pubertal timing and withdrawn depressed problems, and we present preliminary evidence that the family environment may buffer against these neural risk patterns during early adolescence.

Longitudinal Associations Between White Matter Microstructure and Psychiatric Symptoms in Youth

OBJECTIVE

Associations between psychiatric problems and white matter (WM) microstructure have been reported in youth. Yet, a deeper understanding of this relation has been hampered by a dearth of well-powered longitudinal studies and a lack of explicit examination of the bidirectional associations between brain and behavior. We investigated the temporal directionality of WM microstructure and psychiatric symptom associations in youth.

METHOD

In this observational study, we leveraged the world's largest single- and multi-site cohorts of neurodevelopment: the Generation R (GenR) and Adolescent Brain Cognitive Development Studies (ABCD) (total n scans = 11,400; total N = 5,700). We assessed psychiatric symptoms with the Child Behavioral Checklist as broad-band internalizing and externalizing scales, and as syndrome scales (eg, Anxious/Depressed). We quantified WM with diffusion tensor imaging (DTI), globally and at a tract level. We used cross-lagged panel models to test bidirectional associations of global and specific measures of psychopathology and WM microstructure, meta-analyzed results across cohorts, and used linear mixed-effects models for validation.

RESULTS

We did not identify any longitudinal associations of global WM microstructure with internalizing or externalizing problems across cohorts (confirmatory analyses) before, and after multiple testing corrections. We observed similar findings for longitudinal associations between tract-based microstructure with internalizing and externalizing symptoms, and for global WM microstructure with specific syndromes (exploratory analyses). Some cross-sectional associations surpassed multiple testing corrections in ABCD, but not in GenR.

CONCLUSION

Uni- or bi-directionality of longitudinal associations between WM and psychiatric symptoms were not robustly identified. We have proposed several explanations for these findings, including interindividual differences, the use of longitudinal approaches, and smaller effects than expected.

STUDY REGISTRATION INFORMATION

Bidirectionality Brain Function and Psychiatric Symptoms; https://doi.org/10.17605/OSF.IO/PNY92.

Adolescence and the Microbiome: Implications for Healthy Growth and Maturation

The gut microbiota was initially thought to develop into a stable, adult-like profile during early postnatal life. The formation of the gut microbiota during early life has been shown to contribute to healthy growth and has lifelong implications for host health. Adolescence, the developmental period between childhood and adulthood, is a critical window for healthy growth and maturation. The composition of the gut microbiota in adolescents is distinct from that of children and adults, which supports the premise that the gut microbiota continues to develop during adolescence toward an adult-like profile. Research has begun to shift its focus from understanding the gut microbiome at the extremes of the life span to evaluating the importance of the gut microbiome during adolescence and its role in healthy development. This article provides an overview of adolescent development, host-microbiota interactions, and experimental models used to discern effects of gut microbiota on health and disease. Herein, the role of the gut microbiota is reviewed as it relates to adolescent: i) brain development, cognition, and behavior; ii) metabolism and adiposity; and iii) skeletal growth and bone mass accrual. Future directions are addressed, including omics investigations defining mechanisms through which the gut microbiota influences adolescent development. Furthermore, we discuss advancing noninvasive interventions targeting the adolescent gut microbiota that could be employed to support healthy growth and maturation.

Sex steroids and the female brain across the lifespan: insights into risk of depression and Alzheimer's disease

Despite widespread sex differences in prevalence and presentation of numerous illnesses affecting the human brain, there has been little focus on the effect of endocrine ageing. Most preclinical studies have focused on males only, and clinical studies often analyse data by covarying for sex, ignoring relevant differences between the sexes. This sex- (and gender)-neutral approach is biased and contributes to the absence of targeted treatments and services for all sexes (and genders). Female health has been historically understudied, with grave consequences for their wellbeing and health equity. In this Review, we spotlight female brain health across the lifespan by informing on the role of sex steroids, particularly oestradiol, on the female brain and on risk for diseases more prevalent in females, such as depression and Alzheimer's disease.

The positive and negative emotion functions related to loneliness: a systematic review of behavioural and neuroimaging studies

Loneliness is associated with high prevalences of major psychiatric illnesses such as major depression. However, the underlying emotional mechanisms of loneliness remained unclear. We hypothesized that loneliness originates from both decreases in positive emotional processing and increases in negative emotion processing. To test this, we conducted a systematic review of 29 previous studies (total participants n = 19 560, mean age = 37.16 years, female proportion = 59.7%), including 18 studies that included questionnaire measures of emotions only, and 11 studies that examined the brain correlates of emotions. The main findings were that loneliness was negatively correlated with general positive emotions and positively correlated with general negative emotions. Furthermore, limited evidence indicates loneliness exhibited negative and positive correlations with the brain positive (e.g. the striatum) and negative (e.g. insula) emotion systems, respectively, but the sign of correlation was not entirely consistent. Additionally, loneliness was associated with the structure and function of the brain emotion regulation systems, particularly the prefrontal cortex, but the direction of this relationship remained ambiguous. We concluded that the existing evidence supported a bivalence model of loneliness, but several critical gaps existed that could be addressed by future studies that include adolescent and middle-aged samples, use both questionnaire and task measures of emotions, distinguish between general emotion and social emotion as well as between positive and negative emotion regulation, and adopt a longitudinal design that allows us to ascertain the causal relationships between loneliness and emotion dysfunction. Our findings provide new insights into the underlying emotion mechanisms of loneliness that can inform interventions for lonely individuals.

Pubertal maturation and timing effects on resting state electroencephalography in autistic and comparison youth

Autistic and comparison individuals differ in resting-state electroencephalography (EEG), such that sex and age explain variability within and between groups. Pubertal maturation and timing may further explain variation, as previous work has suggested alterations in pubertal timing in autistic youth. In a sample from two studies of 181 autistic and 94 comparison youth (8 years to 17 years and 11 months), mixed-effects linear regressions were conducted to assess differences in EEG (midline power for theta, alpha, and beta frequency bands). Alpha power was analyzed as a mediator in the relation between pubertal maturation and timing with autistic traits in the autistic groups to understand the role of puberty in brain-based changes that contribute to functional outcomes. Individuals advanced in puberty exhibited decreased power in all bands. Those who experienced puberty relatively early showed decreased power in theta and beta bands, controlling for age, sex, and diagnosis. Autistic individuals further along in pubertal development exhibited lower social skills. Alpha mediated the relation between puberty and repetitive behaviors. Pubertal maturation and timing appear to play unique roles in the development of cognitive processes for autistic and comparison youth and should be considered in research on developmental variation in resting-state EEG.

Executive function and underlying brain network distinctions for callous-unemotional traits and conduct problems in adolescents

The complexity of executive function (EF) impairments in youth antisocial phenotypes of callous-unemotional (CU) traits and conduct problems (CP) challenge identifying phenotypic specific EF deficits. We can redress these challenges by (1) accounting for EF measurement error and (2) testing distinct functional brain properties accounting for differences in EF. Thus, we employed a latent modeling approach for EFs (inhibition, shifting, fluency, common EF) and extracted connection density from matching contemporary EF brain models with a sample of 112 adolescents (ages 13-17, 42% female). Path analysis indicated CU traits associated with lower inhibition. Inhibition network density positively associated with inhibition, but this association was strengthened by CU and attenuated by CP. Common EF associated with three-way interactions between density*CP by CU for the inhibition and shifting networks. This suggests those higher in CU require their brain to work harder for lower inhibition, whereas those higher in CP have difficulty engaging inhibitory brain responses. Additionally, those with CP interacting with CU show distinct brain patterns for a more general EF capacity. Importantly, modeling cross-network connection density in contemporary EF models to test EF involvement in core impairments in CU and CP may accelerate our understanding of EF in these phenotypes.

Domain adapted brain network fusion captures variance related to pubertal brain development and mental health

Puberty demarks a period of profound brain dynamics that orchestrates changes to a multitude of neuroimaging-derived phenotypes. This complexity poses a dimensionality problem when attempting to chart an individual's brain development over time. Here, we illustrate that shifts in subject similarity of brain imaging data relate to pubertal maturation in the longitudinal ABCD study. Given that puberty depicts a critical window for emerging mental health issues, we additionally show that our model is capable of capturing variance in the adolescent brain related to psychopathology in a population-based and a clinical cohort. These results suggest that low-dimensional reference spaces based on subject similarities render useful to chart variance in brain development in youths.

Profiling intra- and inter-individual differences in brain development across early adolescence

As we move toward population-level developmental neuroscience, understanding intra- and inter-individual variability in brain maturation and sources of neurodevelopmental heterogeneity becomes paramount. Large-scale, longitudinal neuroimaging studies have uncovered group-level neurodevelopmental trajectories, and while recent work has begun to untangle intra- and inter-individual differences, they remain largely unclear. Here, we aim to quantify both intra- and inter-individual variability across facets of neurodevelopment across early adolescence (ages 8.92 to 13.83 years) in the Adolescent Brain Cognitive Development (ABCD) Study and examine inter-individual variability as a function of age, sex, and puberty. Our results provide novel insight into differences in annualized percent change in macrostructure, microstructure, and functional brain development from ages 9-13 years old. These findings reveal moderate age-related intra-individual change, but age-related differences in inter-individual variability only in a few measures of cortical macro- and microstructure development. Greater inter-individual variability in brain development were seen in mid-pubertal individuals, except for a few aspects of white matter development that were more variable between prepubertal individuals in some tracts. Although both sexes contributed to inter-individual differences in macrostructure and functional development in a few regions of the brain, we found limited support for hypotheses regarding greater male-than-female variability. This work highlights pockets of individual variability across facets of early adolescent brain development, while also highlighting regional differences in heterogeneity to facilitate future investigations in quantifying and probing nuances in normative development, and deviations therefrom.

Morphological abnormalities in youth with bipolar disorder and their relationship to clinical characteristics

OBJECTIVES

To characterize the neuroanatomy of BD in youth and its correlation to clinical characteristics.

METHODS

The current study includes a sample of 105 unmedicated youth with first-episode BD, aged between 10.1 and 17.9 years, and 61 healthy comparison adolescents, aged between 10.1 and 17.7 years, who were matched for age, race, sex, socioeconomic status, intelligence quotient (IQ), and education level. T1-weighted magnetic resonance imaging (MRI) images were obtained using a 4 T MRI scanner. Freesurfer (V6.0) was used to preprocess and parcellate the structural data, and 68 cortical and 12 subcortical regions were considered for statistical comparisons. The relationship between morphological deficits and clinical and demographic characteristics were evaluated using linear models.

RESULTS

Compared with healthy youth, youth with BD had decreased cortical thickness in frontal, parietal, and anterior cingulate regions. These youth also showed decreased gray matter volumes in 6 of the 12 subcortical regions examined including thalamus, putamen, amygdala and caudate. In further subgroup analyses, we found that youth with BD with comorbid attention-deficit hyperactivity disorder (ADHD) or with psychotic symptoms had more significant deficits in subcortical gray matter volume.

LIMITATIONS

We cannot provide information about the course of structural changes and impact of treatment and illness progression.

CONCLUSIONS

Our findings indicate that youth with BD have significant neurostructural deficits in both cortical and subcortical regions mainly located in the regions related to emotion processing and regulation. Variability in clinical characteristics and comorbidities may contribute to the severity of anatomic alterations in this disorder.

Why and How to Account for Sex and Gender in Brain and Behavioral Research

Long overlooked in neuroscience research, sex and gender are increasingly included as key variables potentially impacting all levels of neurobehavioral analysis. Still, many neuroscientists do not understand the difference between the terms "sex" and "gender," the complexity and nuance of each, or how to best include them as variables in research designs. This TechSights article outlines rationales for considering the influence of sex and gender across taxa, and provides technical guidance for strengthening the rigor and reproducibility of such analyses. This guidance includes the use of appropriate statistical methods for comparing groups as well as controls for key covariates of sex (e.g., total intracranial volume) and gender (e.g., income, caregiver stress, bias). We also recommend approaches for interpreting and communicating sex- and gender-related findings about the brain, which have often been misconstrued by neuroscientists and the lay public alike.

Youth Screen Media Activity Patterns and Associations With Behavioral Developmental Measures and Resting-state Brain Functional Connectivity

OBJECTIVE

Screen media activity (SMA) consumes considerable time in youth's lives, raising concerns about the effects it may have on youth development. Disentangling mixed associations between SMA of youth and developmental measures should move beyond overall screen time and consider types and patterns of SMA. This study aimed to identify reliable and generalizable SMA patterns among youth and examine their associations with behavioral developmental measures and developing brain functional connectivity.

METHOD

Three waves of Adolescent Brain and Cognitive Development (ABCD) data were examined. The Lifespan Human Connectome Project in Development (HCP-D) was interrogated as an independent sample. ABCD participants included 11,876 children at baseline. HCP-D participants included 652 children and adolescents. Youth-reported SMA and behavioral developmental measures (neurocognitive performance, behavioral problems, psychotic-like experiences, impulsivity, and sensitivities to punishment/reward) were assessed with validated instruments. We identified SMA patterns in the ABCD baseline data using K-means clustering and sensitivity analyses. Generalizability and stability of the identified SMA patterns were examined in HCP-D data and ABCD follow-up waves, respectively. Relations between SMA patterns and behavioral and brain (resting-state brain functional connectivity) measures were examined using linear mixed effects modeling with false discovery rate (FDR) correction.

RESULTS

SMA data from 11,815 children (mean [SD] age = 119.0 [7.5] months; 6,159 [52.1%] boys) were examined; 3,151 (26.7%) demonstrated a video-centric higher-frequency SMA pattern, and 8,664 (73.3%) demonstrated a lower-frequency pattern. SMA patterns were validated in similarly aged HCP-D youth. Compared with the lower-frequency SMA pattern group, the video-centric higher-frequency SMA pattern group showed poorer neurocognitive performance (β = -.12, 95% CI [-0.08, -0.16], FDR-corrected p < .001), more total behavioral problems (β = .13, 95% CI [0.09, 0.18], FDR-corrected p < .001), and more psychotic-like experiences (β = .31, 95% CI [0.27, 0.36], FDR-corrected p < .001). The video-centric higher-frequency SMA pattern group demonstrated higher impulsivity, more sensitivity to punishment/reward, and altered resting-state brain functional connectivity among brain areas implicated previously in cognitive processes. Most of the associations persisted with age in the ABCD data, with more participants (n = 3,378, 30.4%) in the video-centric higher-frequency SMA group at 1-year follow-up. A social communication-centric SMA pattern was observed in HCP-D adolescents.

CONCLUSION

Video-centric SMA patterns are reliable and generalizable during late childhood. A higher-frequency video entertainment SMA pattern group showed altered resting-state brain functional connectivity and poorer developmental measures that persisted longitudinally. The findings suggest that public health strategies to decrease excessive time spent by children on video entertainment-related SMA are needed. Further studies are needed to examine potential video-centric/social communication-centric SMA bifurcation to understand dynamic changes and trajectories of SMA patterns and related outcomes developmentally.

DIVERSITY & INCLUSION STATEMENT

We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.