Longitudinal trajectories of anterior cingulate glutamate and subclinical psychotic experiences in early adolescence: the impact of bullying victimization.

Previous studies reported decreased glutamate levels in the anterior cingulate cortex (ACC) in non-treatment-resistant schizophrenia and first-episode psychosis. However, ACC glutamatergic changes in subjects at high-risk for psychosis, and the effects of commonly experienced environmental emotional/social stressors on glutamatergic function in adolescents remain unclear. In this study, adolescents recruited from the general population underwent proton magnetic resonance spectroscopy (MRS) of the pregenual ACC using a 3-Tesla scanner. We explored longitudinal data on the association of combined glutamate-glutamine (Glx) levels, measured by MRS, with subclinical psychotic experiences. Moreover, we investigated associations of bullying victimization, a risk factor for subclinical psychotic experiences, and help-seeking intentions, a coping strategy against stressors including bullying victimization, with Glx levels. Finally, path analyses were conducted to explore multivariate associations. For a contrast analysis, gamma-aminobutyric acid plus macromolecule (GABA+) levels were also analyzed. Negative associations were found between Glx levels and subclinical psychotic experiences at both Times 1 (n = 219, mean age 11.5 y) and 2 (n = 211, mean age 13.6 y), as well as for over-time changes (n = 157, mean interval 2.0 y). Moreover, effects of bullying victimization and bullying victimization × help-seeking intention interaction effects on Glx levels were found (n = 156). Specifically, bullying victimization decreased Glx levels, whereas help-seeking intention increased Glx levels only in bullied adolescents. Finally, associations among bullying victimization, help-seeking intention, Glx levels, and subclinical psychotic experiences were revealed. GABA+ analysis revealed no significant results. This is the first adolescent study to reveal longitudinal trajectories of the association between glutamatergic function and subclinical psychotic experiences and to elucidate the effect of commonly experienced environmental emotional/social stressors on glutamatergic function. Our findings may deepen the understanding of how environmental emotional/social stressors induce impaired glutamatergic neurotransmission that could be the underpinning of liability for psychotic experiences in early adolescence.

The longitudinal relationship between dissociative symptoms and self-harm in adolescents: a population-based cohort study.

Previous studies have reported that dissociative symptoms (DIS) are associated with self-harm (SH) in adolescents. However, most of these studies were cross-sectional, which limits the understanding of their theoretical relationship. We aimed to investigate the longitudinal relationship between DIS and SH in the general adolescent population. We used data from the Tokyo Teen Cohort study (N = 3007). DIS and SH were assessed at times 1 and 2 (T1 and T2) (12 years of age and 14 years of age, respectively). DIS were assessed using the parent-report Child Behavior Checklist (CBCL), and severe dissociative symptoms (SDIS) were defined as a score above the top 10th percentile. The experience of SH within 1 year was assessed by a self-report questionnaire. The longitudinal relationship between DIS and SH was examined using regression analyses. Using logistic regression analyses, we further investigated the risk for SH at T2 due to persistent SDIS and vice versa. DIS at T1 tended to predict SH at T2 (odds ratio (OR) 1.11, 95% CI 0.99 to 1.25, p = 0.08), while SH at T1 did not predict DIS at T2 (B = - 0.03, 95% CI - 0.26 to 0.20, p = 0.81). Compared with adolescents without SDIS, those with persistent SDIS had an increased risk of SH at T2 (OR 2.61, 95% CI 1.28 to 5.33, p = 0.01). DIS tended to predict future SH, but SH did not predict future DIS. DIS may be a target to prevent SH in adolescents. Intensive attention should be given to adolescents with SDIS due to their increased risk of SH.

Adolescent psychotic experiences before and during the COVID-19 pandemic: a prospective cohort study.

BACKGROUND: Understanding the etiology of psychosis is essential to the development of preventive interventions. The COVID-19 pandemic provides a rare natural experiment that can expand our understanding of the role of social factors in the trajectories and etiology of psychosis across adolescence, particularly in Tokyo where the prevalence of actual COVID-19 infection remained low. We hypothesized that the likelihood of self-reporting psychotic experiences (PEs) would increase following the onset of the COVID-19 pandemic. METHODS: The Tokyo Teen Cohort (TTC) is a prospective cohort study of adolescents in the general population of the Tokyo metropolitan area, followed from age 10 to 16 years. We used multi-level linear regression models to test the associations between the phase of the COVID-19 pandemic and self-reported PEs. RESULTS: Among 1935 adolescents included in the analysis, a rapid increase in PEs occurred at the onset of the COVID-19 pandemic, following approximately 6 years of steady decline across prior waves. This association was more pronounced for boys compared to girls. This increase became more pronounced as the pandemic moved into later phases, defined based on contemporaneous sociopolitical changes in Tokyo (i.e. changes to school closure, social distancing guidelines, and the state of emergency status). CONCLUSIONS: The steady decline in PEs across adolescence was halted and reversed concurrent with the COVID-19 pandemic onset, despite very low rates of COVID-19 infection. This implicates COVID-19 related socioenvironmental factors as contributory etiological factors in the development of PEs in this adolescent cohort.

Corrigendum: Being praised for prosocial behaviors longitudinally reduces depressive symptoms in early adolescents: a population-based cohort study.

[This corrects the article DOI: 10.3389/fpsyt.2022.865907.].

Characteristic association of symbol coding test score with occupational function in Japanese patients with schizophrenia.

AIM: Studies showed that cognitive function affects occupational function in patients with schizophrenia. This study aimed to determine the effects of cognitive function on occupational function in Japanese patients with schizophrenia using the Brief Assessment of Cognition in Schizophrenia (BACS). METHODS: Participants were 198 outpatients with schizophrenia or schizoaffective disorder (66 females; mean age 34.5 ± 6.8 years). Occupational function was assessed using the work subscale of the Life Assessment Scale for Mental Ill (LASMI-w). Multiple regression analysis was performed using the BACS as the independent variable and LASMI-w as the dependent variable. Furthermore, we divided the LASMI-w score into three groups, <11, 11-20, and >21, and performed a multinomial logistic regression analysis. RESULTS: Multiple regression analysis revealed that LASMI-w score was negatively associated with BACS composite score (ß = -0.20, p < 0.01). Among the sub-items of the BACS, only the symbol-coding score showed a significant negative association (ß = -0.19, p < 0.05). Multinomial logistic analysis showed that the better the composite and symbol coding scores, the smaller the impairment of the occupational function (composite score: ß = 2.39 between mild and moderate occupational impairments, p < 0.05; symbol coding score: ß = 2.44 between mild and severe impairments, p < 0.05). CONCLUSION: The occupational function of patients with schizophrenia was associated with overall cognitive function (composite score). In particular, the symbol coding score of the BACS was suggested to be related to work ability. These results might be useful in the assessment and training of cognitive rehabilitation aimed at employment support.

Lower help-seeking intentions mediate subsequent depressive symptoms among adolescents with high autistic traits: a population-based cohort study.

Adolescents with high autistic traits are at increased risk of depression. Despite the importance of seeking help for early intervention, evidence on help-seeking intentions amongst this population is scarce. Using a population-based cohort in Japan, we examined adolescents' help-seeking intentions and preferences by the level of autistic traits and tested its mediating role on the association between high autistic traits and depressive symptoms. At age 12, we measured parent-rated autistic traits using the short version of the Autism Spectrum Quotient and classified the adolescents into two groups (≥ 6 as AQhigh, < 6 as AQlow); help-seeking intentions and preferences were assessed through a depression vignette. At age 14, depressive symptoms were self-rated using the Short Mood and Feelings Questionnaire. Hypothesised associations between autistic traits and help-seeking intentions or depressive symptoms were tested applying multivariable regression modelling, while mediation was tested with structural equation modelling. Of the 2505 adolescent participants, 200 (8%) were classified as AQhigh. In both groups, the main source of help-seeking was their family; however, 40% of the AQhigh group reported having no help-seeking intentions compared to 27% in the AQlow. The AQhigh group was at increased risk of not having help-seeking intentions (OR 1.84, 95% CI 1.35-2.50) and higher depressive symptoms (b coefficient 1.06, 0.33-1.79). Help-seeking intentions mediated 18% of the association mentioned above. Interventions to promote help-seeking intentions among adolescents with high autistic traits could reduce their subsequent depressive symptoms. Ideally, such interventions should be provided prior to adolescence and with the involvement of their parents.

Auditory Hallucinations and Self-Injurious Behavior in General Population Adolescents: Modeling Within-Person Effects in the Tokyo Teen Cohort.

BACKGROUND AND HYPOTHESES: A wealth of evidence suggests that adolescent psychotic experiences (PEs), and especially auditory hallucinations (AHs), are associated with an increased risk for self-injurious behavior (SIB). However, the directionality and specificity of this association are not well understood, and there are no published studies investigating within-person effects over time. The present study aimed to test whether AHs and SIB prospectively increase reciprocal risk at the individual level during early-to-middle adolescence. STUDY DESIGN: Three waves (12y, 14y, and 16y) of self-reported AHs and SIB data from a large Tokyo-based adolescent birth cohort (N = 2825) were used. Random Intercept Cross-Lagged Panel Model (RI-CLPM) analysis was conducted to test the within-person prospective associations between AHs and SIB. STUDY RESULTS: At the within-person level, AHs were associated with subsequent SIB over the observation period (12y-14y: ß = .118, P < .001; 14-16y: ß = .086, P = .012). The reverse SIB->AHs relationship was non-significant at 12-14y (ß = .047, P = .112) but emerged from 14y to 16y as the primary direction of influence (ß = .243, P < .001). Incorporating depression as a time-varying covariate did not meaningfully alter model estimates. CONCLUSIONS: A complex bi-directional pattern of relationships was observed between AHs and SIB over the measurement period, and these relationships were independent of depressive symptoms. Adolescent AHs may be both a predictor of later SIB and also a manifestation of SIB-induced psychological distress.

Maternal parenting stress from birth to 36 months, maternal depressive symptoms, and physical punishment to 10-year-old children: a population-based birth cohort study.

PURPOSE: This study aimed to investigate the association between parenting stress, maternal depressive symptoms, and use of physical punishment when the child is 10 years old. METHODS: Data from the Tokyo Early Adolescence Survey on early adolescents and primary caregivers (N = 4478) were used. Frequency of using physical punishment, level of depressive symptoms (Kessler Psychological Distress Scale 6), and maternal parenting stress experienced at 1, 3, 9, 18, and 36 months after birth were evaluated. Multiple linear and multinomial logistic regression analyses were conducted. RESULTS: Mothers (1633) who provided information on parenting stress at all the five points were included for the analysis. After controlling for the child's age, sex, birth weight, maternal age, and annual household income, presence of maternal parenting stress at every time point, except at three months after birth, was significantly associated with an increased risk of using physical punishment with the 10-year-old. After adjusting for levels of depressive symptoms, significant associations were found between use of physical punishment and maternal parenting stress at 1 month (adjusted odds ratio [OR] 1.71, 95% confidence interval [Cl] 1.12-2.61) and 36 months (adjusted OR 1.70, 95% CI 1.10-2.61) after birth. CONCLUSION: Maternal parenting stress experienced at 1 and 36 months after birth predicted use of physical punishment, even after adjusting for maternal depressive symptoms. Maternal support should, therefore, be provided to mothers to cope with parenting stress even three years after birth to prevent the use of physical punishment in early adolescence.

Role of advanced glycation end products in the longitudinal association between muscular strength and psychotic symptoms among adolescents.

Muscular strength, assessed by handgrip, is a risk indicator for psychiatric disorders, including psychosis. However, the biological mechanisms underlying this association remain unclear. Since advanced glycation end products (AGEs) play a key role in skeletal muscle underdevelopment and psychosis, we examined the role of AGEs in the longitudinal association between muscular strength and psychotic symptoms among adolescents. We first evaluated the direction of the relationship between handgrip strength and urine levels of pentosidine, a representative AGEs in a population-based birth cohort of 1,542 adolescents at ages 12 and 14. Then, we examined the role of AGEs in the longitudinal association between handgrip strength and thought problems (TP), as a psychotic symptom indicator, in a subsample of 256 adolescents at ages 13 and 14. An autoregressive cross-lagged model revealed that handgrip strength at age 12 negatively predicted pentosidine levels at age 14 (ß = -0.20, p < 0.001), whereas pentosidine levels at age 12 did not predict handgrip strength at age 14 (ß = 0.04, p = 0.062). Moreover, pentosidine levels had a significant indirect effect on the relationship between handgrip strength and TP (standard indirect effect = -0.051, p = 0.012), which remained significant after adjusting for gender and preceded TP and pentosidine levels. Thus, adolescents with low muscular strength are at a high risk of developing psychotic symptoms, which could be mediated by AGEs. Future studies need to investigate whether interventions focused on muscular strength prevent the accumulation of AGEs and thereby prevent the development of psychosis.

Sex-based differences in the longitudinal association between autistic traits and positive psychotic experiences in adolescents: A population-based cohort study.

Previous reports have suggested a cross-sectional association between autistic traits and psychotic experiences (PEs) in adolescents. However, while both autistic traits and PEs show sex-related differences, no studies have directly assessed whether such differences exist in the longitudinal association between autistic traits and PEs. Using a population-based adolescent cohort sample (n = 3007), we tested whether the longitudinal association between autistic traits and positive PEs was affected by sex-based differences using regression analyses. Autistic traits were assessed at 12 years old (timepoint 1 [T1]), and PEs were assessed at 12 and 14 years old (T1 and T2). Subsequently, we tested whether subdomains of autistic traits (difficulties in social interaction, communication, imagination, attention to detail, and attention switching) were associated with subtypes of PEs (auditory hallucinations, visual hallucinations, and delusions) using structural equation modeling, after controlling for PEs at T1, socio-economic status, school performance and parents' psychiatric disorders. After controlling for PEs at T1, we did not find any associations between autistic traits at T1 and PEs at T2 in both sexes. There was no significant positive or negative association between all subdomains of autistic traits and subtypes of PEs in both sexes. Autistic traits do not seem to predict future PEs in general adolescents regardless of sex.

Being Praised for Prosocial Behaviors Longitudinally Reduces Depressive Symptoms in Early Adolescents: A Population-Based Cohort Study.

Background: Depression is highly prevalent and causes a heavy burden in adolescent life. Being praised for prosocial behavior might be a preventive factor because both being praised and prosocial behavior are protective against depression. Here, we investigated the longitudinal relationship between being praised for prosocial behavior and depressive symptoms in adolescents. Methods: In Tokyo Teen Cohort study (TTC), an ongoing prospective population-based cohort study, we collected 3,171 adolescents' data on self-reported experiences of being praised for prosocial behavior, depressive symptoms, and caregiver-evaluated prosocial behavior. Ten-year-old children were asked to freely describe answers to the question "What are you praised for?". Only children who clearly answered that they were praised for their prosocial behavior were designated the "prosocial praise group." The degree of depression at ages 10 and 12 was measured with the Short Mood and Feelings Questionnaire (SMFQ), a self-report questionnaire about depression. Objective prosocial behavior of the 10 year-old children was assessed by the Strength and Difficulty Questionnaire (SDQ). Multiple linear regression analysis was performed using the SMFQ score at age 12 as the objective variable and being praised for prosocial behavior as the main explanatory variable, and the SMFQ score at age 10 and the objective prosocial behavior at age 10 were included as confounders. Results: Depressive symptoms (SMFQ scores) in the "prosocial praise group" were significantly lower than those in the other group both at age 10 (4.3 ± 4.4 vs. 4.9 ± 4.6, p < 0.001) and at age 12 (3.4 ± 4.2 vs. 4.0 ± 4.6, p < 0.01). In the single regression analysis, the children who reported being praised for prosocial behavior at age 10 had significantly lower depressive symptoms at age 12 (partial regression variable: -0.57, 95% confidence interval (CI) [-0.96, -0.17]). This association remained significant after adjusting for confounders, including baseline depressive symptoms (partial regression variable: -0.44, 95% CI [-0.80, -0.08]). Prosocial behavior alone was not associated with depressive symptoms. Conclusions: Being praised for prosocial behavior rather than objective prosocial behavior at 10 years of age predicted lower depressive symptoms 2 years later. Praise for adolescents' prosocial behavior can be encouraged to prevent depression.

Self-Reported Maternal Parenting Stress From 9 m Is Longitudinally Associated With Child ADHD Symptoms at Age 12: Findings From a Population-Based Birth Cohort Study.

Background: Attention-deficit/hyperactivity disorder (ADHD) develops in early childhood and carries lifelong impact, but early identification and intervention ensure optimal clinical outcomes. Prolonged or excessive parenting stress may be a response to infant behavioral differences antecedent to developmental disorders such as ADHD, and therefore represents a potentially valuable inclusion in routine early-life assessment. To investigate the feasibility of using routinely-collected self-reported maternal parenting stress as a risk marker for child ADHD, this study investigated the longitudinal association between maternal parenting stress from 1 to 36 months after childbirth and child ADHD in early adolescence. Methods: The sample comprised 2,638 children (1,253 girls) from the Tokyo Teen Cohort population-based birth cohort study. Mothers recorded parenting stress five times from 1 to 36 months following childbirth in the Maternal and Child Health Handbook, a tool used for routine early-life assessment in Japan. Nine years later, mothers evaluated their child's ADHD symptoms at 12 y using the hyperactivity/inattention subscale from the Strength and Difficulties Questionnaire. Results: Approximately 7.5% of parents reported that they had parenting stress at 36 m after childbirth. 6.2% of children were evaluated as above the cut-off for ADHD symptoms at 12 y. Parenting stress at 1 and 3-4 m was not associated with child ADHD symptoms at 12 y. However, child ADHD symptoms at 12 y was significantly associated with parenting stress at 9-10 m (unadjusted OR = 1.42, p =.047, 95% CI [1.00, 2/00]), 18 m (unadjusted OR = 1.57, p =.007, 95% CI [1.13, 2.19]) and 36 m (unadjusted OR = 1.67, p =.002, 95% CI [1.20, 2.31]). These associations remained after adjustment for child's sex, age in months and family income. Conclusions: We identified associations between parenting stress at 9-10, 18 and 36 m after childbirth and child ADHD symptoms at 12 years old. Self-reported parenting stress data may have utility as an early indicator for ADHD risk. Participation in early-life health checks, assessment of parenting stress, and tailoring support to family needs should be promoted for early identification and intervention for ADHD.

The role of bullying victimization in the pathway between autistic traits and psychotic experiences in adolescence: Data from the Tokyo Teen Cohort study.

Autistic traits are associated with psychotic experiences in adolescence; however, the mechanisms underlying this relationship are not well understood. Prior research indicates that bullying victimization increases the risk of psychotic experiences in general adolescent populations, and autistic youth are at higher risk of being bullied than their non-autistic peers. Using longitudinal data from general population adolescents aged 10-14 in the Tokyo Teen Cohort study, we tested the hypothesis that bullying is responsible for the association between autistic traits and psychotic experiences in adolescence. We identified an indirect effect (estimate = 0.033 [95% CIs: 0.014-0.057], p < 0.001) between autistic traits and psychotic experiences via bullying victimization, even after controlling for known confounders. Prevention of bullying victimization may be one avenue for reducing risk of psychosis among adolescents with high levels of autistic traits.

Bidirectional relationship of problematic Internet use with hyperactivity/inattention and depressive symptoms in adolescents: a population-based cohort study.

Problematic Internet use (PIU), hyperactivity/inattention, and depressive symptoms are comorbid problems in adolescence, but the causal relationships among these issues are unclear. To assess the relationships among PIU, hyperactivity/inattention, and depressive symptoms in adolescents in the general population. This longitudinal cohort study used data from the Tokyo Teen Cohort study in Tokyo, Japan, for two years between October 2012 and January 2015. Of the 3171 pairs of children and parents, 3007 pairs continued to participate in the second wave of the Tokyo Teen Cohort study. A total of 3007 children were included in the analysis (mean [standard deviation] age, 9.7 [0.4] years; 1418 women [47.2%]. Cross-lagged panel analysis revealed that PIU at timepoint 1 was significantly associated with hyperactivity/inattention at timepoint 2 (ß = 0.03; 95% confidence interval (CI) 0.01-0.06), and hyperactivity/inattention at timepoint 1 was also significantly associated with PIU at timepoint 2 (ß = 0.07; 95% CI 0.04-0.10), even after adjustments were made for depressive symptoms. Furthermore, PIU at timepoint 1 was significantly associated with depressive symptoms at timepoint 2 (ß = 0.05; 95% CI 0.01-0.12), and depressive symptoms at timepoint 1 were also significantly associated with PIU at timepoint 2 (ß = 0.05; 95% CI 0.02-0.07), even after adjustments were made for hyperactivity/inattention. These results support the bidirectional relationships among PIU, hyperactivity/inattention, and depressive symptoms. PIU may be a target to improve hyperactivity/inattention and depressive symptoms in adolescents.

Psychotic experiences predict subsequent loneliness among adolescents: A population-based birth cohort study.

BACKGROUND: Cross-sectional studies have suggested that the occurrence of psychotic experiences is associated with loneliness in the general adolescent population. However, there has been a scarcity of prospective longitudinal studies on this topic. METHODS: We investigated the longitudinal association between the presence of psychotic experiences and loneliness among adolescents using data from a population-based birth cohort study (Tokyo Teen Cohort; N = 3171). Psychotic experiences and loneliness were assessed at three timepoints with two-year intervals through early adolescence (age 10, 12, and 14). RESULTS: After adjusting for demographic characteristics and potential confounding factors, linear regression analyses showed a significant longitudinal association between psychotic experiences and subsequent loneliness (for age 10 to 12: B = 0.041, 95% CI: 0.009-0.074, p = .013; for age 12 to 14: B = 0.061, 95% CI: 0.026-0.096, p = .001). The reverse association, between preceding loneliness and later psychotic experiences, was not significant (for age 10 to 12: B = 0.003, 95% CI: -0.052-0.057, p = .926; for age 12 to 14: B = -0.028, 95% CI: -0.088-0.032, p = .355). DISCUSSION: Loneliness could be a sign of underlying psychotic experiences among adolescents but does not appear to be antecedent to these symptoms. Clinicians and teachers should assess for the presence of psychotic experiences in young adolescents who report loneliness. Future studies capturing PEs and loneliness at narrower time intervals, and including other potential mediators and confounders, may be insightful.

Young carers in Japan: Reliability and validity testing of the BBC/University of Nottingham young carers survey questionnaire and prevalence estimation in 5000 adolescents.

Aim: Young carers (YCs) refer to children under the age of 18 who assume responsibilities that would normally be assumed by adults, such as caring for family members in need of care. In recent years, the concept of YCs has been expanding in Japan, and the government has been rapidly implementing strategies to support them. There is a need for a survey scale for YCs that uses standardized methods that can be compared internationally. Method: The BBC/University of Nottingham Survey for estimating the prevalence of YCs and caring activities of United Kingdom adolescents was translated into Japanese, and its reliability and validity were tested with 313 adolescents. Moreover, the prevalence of YCs was estimated in a school-based survey among 5000 adolescents. Results: The Young Carers Scale Japanese version (YCS-J) was acceptably reliable and valid. The original six-factor model for caring activity in the Multidimensional Assessment of Caring Activities Checklist for Young Carers (MACA-YC18) was supported by confirmatory factor analysis. The prevalence of YCs among 5000 adolescents in the Tokyo metropolitan area was estimated to be 7.4%, comparable to that reported in Western countries and in recent surveys in Japan using nonstandardized methods. YCs exhibited significantly higher scores for prosocial behavior and emotional symptoms than non-YCs. Conclusions: The YCS-J, as an internationally comparable instrument, will be useful for understanding the actual situation of YCs in Japan, and to disseminate and implement support through cooperation among education, welfare, and healthcare sectors.

Longitudinal Bidirectional Relationships Between Maternal Depressive/Anxious Symptoms and Children's Tic Frequency in Early Adolescence.

Background: Previous studies have revealed an association between maternal depressive/anxious symptoms and children's tics. However, the longitudinal relationships between these symptoms remain unclear. We examined the longitudinal relationships between maternal depressive/anxious symptoms and children's tic frequency in early adolescence with a population-based sample. Methods: The participants consisted of 3,171 children and their mothers from the Tokyo Teen Cohort (TTC) study, a population-representative longitudinal study that was launched in Tokyo in 2012. Maternal depressive/anxious symptoms and children's tics were examined using self-report questionnaires at the ages of 10 (time 1, T1) and 12 (time 2, T2). A cross-lagged model was used to explore the relationships between maternal depressive/anxious symptoms and children's tic frequency. Results: Higher levels of maternal depressive/anxious symptoms at T1 were related to an increased children's tic frequency at T2 (ß = 0.06, p < 0.001). Furthermore, more frequent children's tics at T1 were positively related to maternal depressive/anxious symptoms at T2 (ß = 0.06, p < 0.001). Conclusions: These findings suggest a longitudinal bidirectional relationship between maternal depressive/anxious symptoms and children's tic frequency in early adolescence that may exacerbate each other over time and possibly create a vicious cycle. When an early adolescent has tics, it might be important to identify and treat related maternal depressive/anxious symptoms.

Birth order and prosociality in the early adolescent brain.

Birth order is a crucial environmental factor for child development. For example, later-born children are relatively unlikely to feel secure due to sibling competition or diluted parental resources. The positive effect of being earlier-born on cognitive intelligence is well-established. However, whether birth order is linked to social behavior remains controversial, and the neural correlates of birth order effects in adolescence when social cognition develops remain unknown. Here, we explored the birth order effect on prosociality using a large-scale population-based adolescent cohort. Next, since the amygdala is a key region for sociality and environmental stress, we examined amygdala substrates of the association between birth order and prosociality using a subset neuroimaging cohort. We found enhanced prosociality in later-born adolescents (N = 3160), and observed the mediating role of larger amygdala volume (N = 208) and amygdala-prefrontal functional connectivity with sex-selective effects (N = 183). We found that birth order, a non-genetic environmental factor, affects adolescent social development via different neural substrates. Our findings may indicate the later-born people's adaptive survival strategy in stressful environments.

Association between duration of breastfeeding based on maternal reports and dorsal and ventral striatum and medial orbital gyrus volumes in early adolescence.

Maternal breastfeeding has an impact on motor and emotional development in children of the next generation. Elucidating how breastfeeding during infancy affects brain regional structural development in early adolescence will be helpful for promoting healthy development. However, previous studies that have shown relationships between breastfeeding during infancy and cortical brain regions in adolescence are usually based on maternal retrospective recall of breastfeeding, and the accuracy of the data is unclear. In this study, we investigated the association between breastfeeding duration and brain regional volume in a population-neuroimaging study of early adolescents in Japan (N â€‹= â€‹207; 10.5-13.4 years) using voxel-based morphometry, which enabled us to analyze the whole brain. We evaluated breastfeeding duration as indexed by maternal and child health handbook records during infancy. The results showed a significant positive correlation between the duration of breastfeeding and gray matter volume in the dorsal and ventral striatum and the medial orbital gyrus. Post hoc exploratory analyses revealed that the duration of breastfeeding was significantly correlated with emotional behavior. Additionally, the volume in the medial orbital gyrus mediated an association between breastfeeding duration and emotional behavior. This is the first study to evaluate the effect of breastfeeding during infancy on regional brain volumes in early adolescence based on maternal and child health handbook records. Our findings shed light upon the importance of maternal breastfeeding for brain development related to emotional and motivational processing in early adolescence.

Neurometabolic underpinning of the intergenerational transmission of prosociality.

Parent-child personality transmission can occur via biological gene-driven processes as well as through environmental factors such as shared environment and parenting style. We recently revealed a negative association between prosociality, a highly valued personality attribute in human society, and anterior cingulate cortex (ACC) γ-aminobutyric acid (GABA) levels in children at the age of 10 years. We thus hypothesized that prosociality would be intergenerationally transmitted, and that transmission would be underwritten by neurometabolic heritability. Here, we collected prosociality data from children aged 10 years and their parents in a large-scale population-based birth cohort study. We also measured ACC GABA+ and glutamate plus glutamine (Glx) levels in a follow-up assessment with a subsample of the participants (aged 11 years) using magnetic resonance spectroscopy. We analyzed the associations among children's and parents' prosociality and GABA+/Glx ratios. We also examined the effect of socioeconomic status (SES) and verbalized parental affection (VPA) on these associations. We found a significant positive parent-child association for prosociality (N â€‹= â€‹3026; children's mean age 10.2 years) and GABA+/Glx ratio (N â€‹= â€‹99; children's mean age 11.4 years). There was a significant negative association between GABA+/Glx ratio and prosociality in both children (N â€‹= â€‹208) and parents (N â€‹= â€‹128). Our model accounting for the effects of neurometabolic heritability on prosociality transmission fitted well. Moreover, in this model, a significant positive effect of VPA but not SES on children's prosociality was observed independently of the effect of neurometabolic transmission, while SES but not VPA was significantly associated with parental prosociality. Our results provide novel insights into the neurometabolic substrates of parent-child transmission of social behavior.