Critical Developmental Period Research Articles

A novel developmental critical period of orexinergic signaling in the primary visual thalamus

The orexinergic system of the lateral hypothalamus plays crucial roles in arousal, feeding behavior, and reward modulation. Most research has focused on adult rodents, overlooking orexins' potential role in the nervous system development. This study, using electrophysiological and molecular tools, highlights importance of orexinergic signaling in the postnatal development of the rodent dorsolateral geniculate nucleus (DLG), a primary visual thalamic center. Orexin activation of DLG thalamocortical neurons occurs in a brief seven-day window around eye-opening, concurrent to transient OX2 receptor expression. Blocking OX2 receptors during this period reduces sensitivity of DLG neurons to green and blue light and lowers spontaneous firing rates in adulthood. This research reveals critical and temporally confined role of orexin signaling in postnatal brain development, emphasizing its contribution to experience-dependent refinement in the DLG and its long-term impact on visual function.

Parents and caregivers as key players in the prevention and identification of body image concerns and eating disorders among early adolescents

ABSTRACT Early adolescence (ages 11–14 years) is a key period for the emergence of body image and eating concerns, and early identification and access to treatment are imperative for positive outcomes. Despite research identifying this critical developmental period, few prevention resources are available for early adolescents. Parents are key players for this age group and important socializing agents. As such, they are well positioned to help youth access resources or support where needed. However, programs to position and involve parents as interventionists are lacking. Our aims are two-fold. First, we review the evidence for the effectiveness of parents as body image interventionists and the existing data regarding parental needs. Second, we provide directions for future research and outline a framework for empowering parents as interventionists, identifying key domains in which parents may play a role in addressing body image and eating concerns among early adolescents. Based on the extent literature, these domains include facilitating engagement with or co-utilizing intervention content to decrease body image and eating concerns in at-risk children, which may also help to increase parents’ effectiveness in their efforts to support youth. In addition, parents may deliver content to decrease or reverse risk-factors and early symptoms, or disrupt the early disorder phase of illness. To date, parents constitute an underutilized resource in eating disorder and disordered eating prevention, and efforts should be made to increase the evidence-based strategies to leverage their relationship with at-risk children.

2045-LB: Target-Derived Factors Decrease Sympathetic Innervation of Brown Adipose Tissue in a Critical Period of Development

2045-LB: Target-Derived Factors Decrease Sympathetic Innervation of Brown Adipose Tissue in a Critical Period of Development

Пубертатний стрес спричиняє статевоспецифічні репродуктивні ефекти у дорослих щурів

Adolescence is one of the critical periods of individual development, which is highly sensitive to changes caused by stress factors. Stress-related hormonal imbalances can negatively affect puberty and reproductive function. The aim of the study was to investigate the long-lasting reproductive effects of chronic pubertal stress in rats. Animals were subjected to immobilization stress daily from 30 to 45 postnatal day by placing them for 1 h in cylinders 4.5 cm in diameter and 10 cm in long, equipped with breathing holes. The timing of puberty in animals was studied and their somatic development was assessed. Further studies were conducted in 6-month-old sexually mature rats. The results were compared with the corresponding parameters in intact animals. Pubertal stress delayed sexual maturation in females and decreased weight gain in males. In adult animals of both sexes, pubertal stress did not change testosterone levels or the weight and morphology of the gonads significantly, except for minor vacuolation of the spermatogenic epithelium. The spermatogenesis index in the experimental group was significantly lower than in the control, due to a decrease in the number of late spermatids. Pubertal stress led to a 25.9% decrease in the number of spermatozoa in epididymal washes, an increase in the number of their pathological forms and a 2.4-fold slowdown in oxidative-reductive processes in spermatozoa. The content of malonic dialdehyde increased in the testes and ovaries, which indicates the activation of lipid peroxidation. Thus, chronic pubertal stress led to a decrease in the reproductive potential of male rats. Females are less susceptible to the negative effects of pubertal stress.

Pricing the priceless childcare: Early childhood education for babies and toddlers.

This article connects Viviana Zelizer's theory of the social meaning of money to family studies, using the case of American parents' spending on children. We investigate how money spent on the youngest children-babies and toddlers-reflects the growing expert emphasis on the importance of parental investment in the critical early period for child development. First, we review literature on expert knowledge to trace the shift in increasing emphasis on the importance of building children's cognitive skills through formal education beginning in infancy, offered in center-based care, moving from spaces of "childcare" to "early childhood education" centers. Second, we use quantitative data from the Consumer Expenditure Survey (1995-2017) to show that parents have increasingly spent money, and an increasing share of their income, on center-based care for babies and toddlers but not on otherchild items. Additionally, lower income families have been spending a greater share of their income on center-based care for their infants than other families. We interpret our findings using Zelizer's theory about the cultural influences on the meaning of money, showing how these can be expert-led and persist even when families are faced with structural economic constraints.

An interpretative phenomenological analysis of the psychosexual identity development in adolescent and young adult survivors of testicular cancer.

Qualitative research has explored how some testicular cancer survivors (TCS) experience the psychological impacts of diagnosis and treatment. More research into the impacts of testicular cancer (TC) on adolescent and young adults (AYA) is needed due to the critical period of identity development. The present study aimed to explore how AYA with TC appraise and make sense of their experience and to develop a greater understanding of psychosexual identity development in AYA TCS. Eight AYA TCS were interviewed. The results were analysed using Interpretative Phenomenological Analysis. The questions explored the experiences relating to diagnosis and treatment, how it affected their psychosexual identity development (e.g., sexual relationships and self-image) and the meanings attached to the experiences. Four Group Experiential Themes were developed from the data; 'Dealing with the shock', 'Fear and weight of responsibility', 'those closest to me' and 'sense of change'. The AYA TCS experiences may result in adoption of traditional masculine traits (e.g., stoicism) or abandonment of traditionally masculine traits (E.g. violence and aggression). AYA TCS also described feelings of insecurity when compared to other men. Psychology input could help manage stoicism and feelings of inferiority when compared to men with two testicles.

NARP-related alterations in the excitatory and inhibitory circuitry of socially isolated mice: developmental insights and implications for autism spectrum disorder.

Social isolation during critical periods of development is associated with alterations in behavior and neuronal circuitry. This study aimed to investigate the immediate and developmental effects of social isolation on firing properties, neuronal activity-regulated pentraxin (NARP) and parvalbumin (PV) expression in the prefrontal cortex (PFC), social behavior in juvenile socially isolated mice, and the biological relevance of NARP expression in autism spectrum disorder (ASD). Mice were subjected to social isolation during postnatal days 21-35 (P21-P35) and were compared with group-housed control mice. Firing properties in the PFC pyramidal neurons were altered in P35 socially isolated mice, which might be associated with alterations in NARP and PV expression. In adulthood, mice that underwent juvenile social isolation exhibited difficulty distinguishing between novel and familiar mice during a social memory task, while maintaining similar levels of social interaction as the control mice. Furthermore, a marked decrease in NARP expression in lymphoblastoid cell lines derived from adolescent humans with ASD as compared to typically developing (TD) humans was found. Our study highlights the role of electrophysiological properties, as well as NARP and PV expression in the PFC in mediating the developmental consequences of social isolation on behavior.

Internet addiction and depressive symptoms in adolescents: joint trajectories and predictors.

Internet addiction and depressive symptoms are common mental health problems in adolescents. Due to the comorbidity of Internet addiction and depressive symptoms, their mutual relationship influences their developmental trajectories over time. Thus, this study aimed to identify the joint trajectories of Internet addiction and depressive symptoms, and examined the individual, family, and school antecedents of these trajectories among Chinese adolescents. Using a battery of self-report scales, three waves of data collection were conducted in a Chinese adolescent sample (N = 1,301). The co-developmental trajectories of Internet addiction and depressive symptoms were extracted by adopting parallel-process latent class growth modeling (PPLCGM). Multinomial logistic regression was performed to assess predictive factors. Four unique joint trajectory classes were detected: the Health Group (n = 912, 70.1%), Comorbidity-Worsening Group (n = 85, 6.5%), Asymptomatic-Comorbid Risk Group (n = 148, 11.4%), and Prominent Depressive Symptoms-Remission Group (n = 156, 12.0%). Individual, family, and school factors (e.g., gender, positive youth development, family function, academic performance) significantly predicted the membership in these distinct co-developmental trajectories. Our findings illustrate that the joint development of Internet addiction and depressive symptoms among adolescents presents a heterogeneous distribution, which could better inform prevention and intervention strategies since each co-developmental trajectory may represent unique experience for adolescents who need targeted treatment. Various individual, family, and school factors are important predictors that play different roles in distinguishing the joint trajectories of Internet addiction and depressive symptoms during this critical developmental transition period.

Preference for digital media use, biobehavioral attention bias, and anxiety symptoms in adolescents

Adolescence is a critical developmental period of biological and social change during which 1 in 3 youth experience significant anxiety symptoms. The social-emotional lives of the majority of adolescents are largely conducted via digital media use (DMU; e.g., social media, text messaging). Yet the past decade of research on DMU and anxiety has yielded mixed results (e.g., Keles et al., 2020 review), leaving the complex role that DMU might play in the emergence and maintenance of anxiety poorly understood. A key step forward is to leverage psychophysiology to identify individual differences in cognitive and emotional processes that confer vulnerability to potential negative effects of DMU. Further, given the ubiquity of DMU, a greater focus is needed on measurements that move beyond sheer frequency to capture DMU in comparison to face-to-face (FTF) social interactions. This study examined attention bias (AB), characterized by selective and exaggerated attention toward or away from threat, as a moderator of the link between DMU and anxiety in adolescents (N = 75; 42 female) aged 12–14 years (M = 13.28, SD = 0.87). AB was indexed during a dot probe task using reaction time metrics (i.e., trial-level bias) and via ERPs capturing attentional selection and discrimination (N170) and cognitive control (N2) to threat compared to neutral faces. AB moderated associations between DMU and anxiety. A greater preference to use DMU vs FTF predicted greater anxiety among those with a greater behavioral bias away from threat, blunted N170, and blunted N2 in the presence of threat. Future research should examine potential causal and bidirectional links between DMU and anxiety and explore whether preferences for technology-mediated interactions and individual differences in threat processing increase risk.

Similarities and differences between eating disorders and obsessive-compulsive disorder in childhood and adolescence: a systematic review.

The developmental age, comprising childhood and adolescence, constitutes an extremely important phase of neurodevelopment during which various psychiatric disorders can emerge. Obsessive-Compulsive Disorder (OCD) and Eating Disorders (ED) often manifest during this critical developmental period sharing similarities but also differences in psychopathology, neurobiology, and etiopathogenesis. The aim of this study is to focus on clinical, genetic and neurobiological similarities and differences in OCD and ED. This study is based on a PubMed/MEDLINE and Cochrane Central Register for Controlled Trial (CENTRAL). The research adhered to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The aforementioned search yielded an initial collection of 335 articles, published from 1968 to September 2023. Through the application of inclusion and exclusion criteria, a total of 324 articles were excluded, culminating in a final selection of 10 articles. Our findings showed both differences and similarities between OCD and ED. Obsessive-compulsive (OC) symptoms are more prevalent in ED characterized by a binge/purge profile than in those with a restrictive profile during developmental age. OC symptomatology appears to be a common dimension in both OCD and ED. When presents, OC symptomatology, exhibits transversal characteristic alterations in the anterior cingulate cortex and poorer cognitive flexibility. These correlations could be highlighted by genetic overlaps between disorders. A comprehensive definition, integrating psychopathological and neurobiological aspects could significantly aid treatment selection and thereby influence the prognosis of these patients.

Developmental hearing loss–induced perceptual deficits are rescued by genetic restoration of cortical inhibition

Even a transient period of hearing loss during the developmental critical period can induce long-lasting deficits in temporal and spectral perception. These perceptual deficits correlate with speech perception in humans. In gerbils, these hearing loss-induced perceptual deficits are correlated with a reduction of both ionotropic GABAA and metabotropic GABAB receptor-mediated synaptic inhibition in auditory cortex, but most research on critical period plasticity has focused on GABAA receptors. Therefore, we developed viral vectors to express proteins that would upregulate gerbil postsynaptic inhibitory receptor subunits (GABAA, Gabra1; GABAB, Gabbr1b) in pyramidal neurons, and an enzyme that mediates GABA synthesis (GAD65) presynaptically in parvalbumin-expressing interneurons. A transient period of developmental hearing loss during the auditory critical period significantly impaired perceptual performance on two auditory tasks: amplitude modulation depth detection and spectral modulation depth detection. We then tested the capacity of each vector to restore perceptual performance on these auditory tasks. While both GABA receptor vectors increased the amplitude of cortical inhibitory postsynaptic potentials, only viral expression of postsynaptic GABAB receptors improved perceptual thresholds to control levels. Similarly, presynaptic GAD65 expression improved perceptual performance on spectral modulation detection. These findings suggest that recovering performance on auditory perceptual tasks depends on GABAB receptor-dependent transmission at the auditory cortex parvalbumin to pyramidal synapse and point to potential therapeutic targets for developmental sensory disorders.

Anthropometric Influence on Preschool Children's Physical Fitness and Motor Skills: A Systematic Review.

Early childhood is a critical period for physical and motor development with implications for long-term health. This systematic review examined the relationship between anthropometric characteristics and measures of physical fitness and motor skills in preschool-aged children (typically 2-6 years). The search strategy was applied in four databases (PubMed, ProQuest Central, Scopus, and Web of Science) to find articles published before 11 April 2024. The results consistently demonstrated significant associations between anthropometric variables (height, weight, body mass index [BMI], body composition) and physical performance measures. Notably, height and mass were often better predictors of fitness status than BMI alone. Indicators of undernutrition (stunting, wasting) were negatively associated with motor development, emphasizing the importance of adequate nutrition. While some studies reported impaired fitness and motor skills among overweight/obese preschoolers compared to normal-weight peers, others found no differences based on weight status. Relationships between physical activity levels, anthropometrics, and motor outcomes were complex and inconsistent across studies. This review highlights key findings regarding the influence of anthropometric factors on physical capabilities in early childhood. Early identification of children with impaired growth or excessive adiposity may inform tailored interventions to promote optimal motor development and prevent issues like obesity. Creating supportive environments for healthy growth and age-appropriate physical activity opportunities is crucial during this critical developmental window.

The Effect of Childhood Maltreatment on Violent Behavior in Adulthood

Childhood is the fastest and most critical developmental period for individuals to develop emotional and cognitive abilities. If children are abused, neglected, or raised in a family with traumatic experiences and dysfunctional dynamics during childhood, it is very likely to have an impact on their future development during adulthood. This review mainly discusses the contribution of childhood maltreatment to adult violent behavior. Previous studies on different aspects in the same direction were analyzed. It was found that with the trajectory, the negative impact of childhood maltreatment will not be reduced. Severity of maltreatment and later violent behavior, gender, experiences of different types of abuse, shame, personality disorder and some protective factors serve as mediators to varying degrees. Among them, psychopathy is a controversial intermediary factor. One study indicated that it could function as an intermediary factor, while another article only found it as a factor leading to violent behavior, and there was no evidence to prove the impact of maltreatment on it. This review can provide some guidance to the design of intervention programs for children in need.

Scientific Literacy, Professional Development, and Support of Teachers in Selected Kindergarten Schools in Guiyang City, China

The study aimed to address the critical issues of scientific literacy among the selected kindergarten teachers by comprehensively assessing their current level of scientific literacy and identifying the influencing factors. The research design was a descriptive quantitative design aimed at assessing and developing the scientific literacy of kindergarten teachers. The primary respondents of this study were teachers from three selected kindergartens in Guiyang City, Guizhou Province. These 147 teachers were responsible for the care and education of children aged 3 to 6 years old in three different early childhood institutions. By focusing on kindergarten teachers, recognizes the direct influence of teachers' scientific literacy on children's scientific literacy in the critical period of children's development. The study concluded:1. The main characteristics of kindergarten teachers in Guiyang City include a predominant age distribution of less than 25 years old, a preponderance of females, a predominance of undergraduate degrees, and a preponderance of 0-3 years of experience in kindergarten teaching. These characteristics provide basic information for understanding the overall literacy level of teachers.2. The overall level of scientific literacy of kindergarten teachers is good. Teachers' mean score of 3.04 in the areas of scientific knowledge, instructional practices, and use of resources indicates that teachers overall have a good level of understanding and application of scientific literacy.3. The personal background of kindergarten teachers had less influence on scientific literacy. Educational background factors such as age, gender, academic qualifications and teaching experience had a small effect on teachers' level of scientific literacy, indicating that educators had relatively consistent levels of scientific literacy across different characteristics.4. Kindergarten teachers are actively involved in professional development. Teachers' mean score for professional development and support was 2.89, indicating that teachers as a whole were actively involved in professional development activities and received some level of support.5. kindergarten teachers' personal backgrounds had less impact on professional development. There were no significant differences in the level of career development and support among teachers of different ages, genders, academic qualifications and teaching experience, indicating that these factors have less influence on teachers' career development support.6. Scientific literacy of kindergarten teachers is significantly associated with career development. There is a significant positive correlation between teachers' level of scientific literacy and their career development and support, emphasizing the importance of improving teachers' scientific literacy for their career development.

The impact of social network use on adolescent depression: the chain mediation between self-objectification and body satisfaction.

Adolescents are in the transitional stage from childhood to adulthood, a critical period for individual physical and mental development. With the rapid development of the Internet, social networking has become an integral part of adolescents' daily lives. However, the information that adolescents are exposed to on social networks is often processed and embellished, which may cause them to become physically dissatisfied and lead to emotional problems, such as depression. We investigated the chain-mediating effects of self-objectification and body satisfaction on the relationship between social network use and depression. We utilized questionnaire data of 2025 adolescents from two secondary schools and one high school in China. Our results demonstrated that (1) there are obvious sex differences in the intensity of social network use and active and passive social network use among adolescents, with usage higher among girls than for boys; (2) self-objectification and body satisfaction play a mediating role in the relationship between the intensity of social network use and adolescent depression, as well as the presence of chain-mediating roles; and (3) self-objectification and body satisfaction play an intermediary role in the relationship between active and passive social network use and adolescent depression; there is further a chain intermediary role. The findings suggest that social network use affects adolescents' depression through self-objectification and body satisfaction, which is not only manifested in the general use intensity of social networks but also in their active and passive use modes of social networks. This study provides theoretical support for the causes and mechanisms behind the influence of social network use on adolescent depression and has practical implications for the prevention and intervention of adolescent emotional problems.

Photosynthetic productivity of soybean (Glycine max L.) crops under various fertilization options and pre-sowing seed treatment

The objective of the research is to determine the impact of basic fertilization options, foliar feeding with organo-mineral fertilizer during critical periods of soy plant development, pre-sowing seed treatment with mycorrhizal biofertilizer, and mycorrhizal inoculant in combination with a fungicide on the dynamics of dry matter accumulation by the plants and the net productivity of photosynthesis in the soy crop. Methods. Field (for studying the interaction of the research object with biotic and abiotic factors); morphophysiological (for biological monitoring of productivity elements development during organogenesis stages); statistical (statistical analysis of research results). Results. The article presents research findings on the accumulation of dry matter by soy plants and the net productivity of photosynthesis in the crop across different growth and development stages. Equations have been calculated to establish the relationship between soy seed yield and the indicators of dry mass accumulation by the plants during the pod-filling phase. Conclusions. In modern agricultural practices aimed at achieving maximum seed yield, cultivation technology should include agronomic measures directed towards meeting the biological needs of the plant throughout the vegetation period and reducing the influence of adverse external factors. The highest levels of dry matter accumulation by plants in the study — 26.8–29.2 g/plant, were noted during the pod filling phase in variants with the application of N15P45K60+N30 fertilization, sowing seeds treated with mycorrhizal biopreparation and fungicide, and foliar feeding with organo-mineral fertilizers during the budding and flowering phases. The maximum indicators of net photosynthetic productivity of the crop in the study (8.52–11.29 g/m2×day compared to 5.46 g/m2×day in the absolute control) were observed during the interphase period of flowering and pod filling in variants with N45P45K60 fertilization. For the optimal seed yield of soybean variety Muza observed in the study, the optimal conditions were provided by a cultivation technology involving the application of N15P45K60+N30 fertilizers, pre-sowing seed treatment with mycorrhizal inoculant in combination with fungicide, as well as foliar feeding with organo-mineral fertilizers during the branching or budding phases, when the plants are forming flowers, pods, and seeds within the pods. Through the combination of these agronomic measures, plants accumulate dry matter during the pod filling phase at 25.9–27.4 g/plant, ensuring the net photosynthetic productivity of the crop during this developmental period at 5.60–6.10 g/m2×day, compared to 20.8 g/plant and 5.46 g/m2×day observed in the absolute control, respectively.

Impact of a philosophical intervention on the reduction of depression in high school students.

Adolescence is a critical and challenging period in development; therefore, it is of utmost importance to address and prevent disorders such as depression or anxiety. The present study aimed to evaluate the effect of a philosophical intervention on depression rates in high school students. The method consisted of the evaluation of depression before and after the intervention with the BDI-Y test. Of the cases of the young people attended in the intervention workshops, on average, their depressive classification decreased by 67%. The implementation of the workshops with content in ethical values can be a model of early mental health intervention to reduce the levels of depression in high school students, which created a multiplier effect in the class groups, as well as in the increase of coexistence and teamwork.

Polygenic architecture of brain structure and function, behaviors, and psychopathologies in children.

The human brain undergoes structural and functional changes during childhood, a critical period in cognitive and behavioral development. Understanding the genetic architecture of the brain development in children can offer valuable insights into the development of the brain, cognition, and behaviors. Here, we integrated brain imaging-genetic-phenotype data from over 8,600 preadolescent children of diverse ethnic backgrounds using multivariate statistical techniques. We found a low-to-moderate level of SNP-based heritability in most IDPs, which is lower compared to the adult brain. Using sparse generalized canonical correlation analysis (SGCCA), we identified several covariation patterns among genome-wide polygenic scores (GPSs) of 29 traits, 7 different modalities of brain imaging-derived phenotypes (IDPs), and 266 cognitive and psychological phenotype data. In structural MRI, significant positive associations were observed between total grey matter volume, left ventral diencephalon volume, surface area of right accumbens and the GPSs of cognition-related traits. Conversely, negative associations were found with the GPSs of ADHD, depression and neuroticism. Additionally, we identified a significant positive association between educational attainment GPS and regional brain activation during the N-back task. The BMI GPS showed a positive association with fractional anisotropy (FA) of connectivity between the cerebellum cortex and amygdala in diffusion MRI, while the GPSs for educational attainment and cannabis use were negatively associated with the same IDPs. Our GPS-based prediction models revealed substantial genetic contributions to cognitive variability, while the genetic basis for many mental and behavioral phenotypes remained elusive. This study delivers a comprehensive map of the relationships between genetic profiles, neuroanatomical diversity, and the spectrum of cognitive and behavioral traits in preadolescence.

Impact of Prenatal LPS and Early-life Constant Light Exposure on Circadian Gene Expression Profiles in Various Rat Tissues

Exposure to lipopolysaccharide (LPS) during prenatal development leads to various changes in neurobiological and behavioural patterns. Similarly, continuous exposure to constant light (LL) during the critical developmental period of the circadian system affects gene expression in various tissues in adulthood. Given the reciprocal nature of the interaction between the circadian and the immune systems, our study primarily investigated the individual effects of both interventions and, more importantly, their combined effect. We aimed to explore whether there might be a potential synergistic effect on circadian rhythms and their parameters, focussing on the expression of clock genes, immune-related genes, and specific genes in the hippocampus, pineal gland, spleen and adrenal gland of rats at postnatal day 30. Our results show a significant influence of prenatal LPS and postnatal LL on the expression profiles of all genes assessed. However, the combination of prenatal LPS and postnatal LL only revealed an enhanced negative effect in a minority of the comparisons. In most cases, it appeared to attenuate the changes induced by the individual interventions, restoring the measured parameters to values closer to those of the control group. In particular, genes such as Nr1d1, Aanat and Tph1 showed increased amplitude in the pineal gland and spleen, while the kynurenine enzymes Kynu and KatII developed circadian rhythmicity in the adrenal glands only after the combined interventions. Our data suggest that a mild immunological challenge during prenatal development may play a critical role in triggering an adaptive response of the circadian clock later in life.

Deciduous teeth from the New Hampshire birth cohort study: Early life environmental and dietary predictors of dentin elements

BackgroundSparse research exists on predictors of element concentrations measured in deciduous teeth. ObjectiveTo estimate associations between maternal/child characteristics, elements measured in home tap water during pregnancy and element concentrations in the dentin of shed deciduous teeth. MethodsOur analysis included 152 pregnant person-infant dyads followed from the second trimester through the end of the first postnatal year from the New Hampshire Birth Cohort Study. During pregnancy and early infancy, we collected dietary and sociodemographic information via surveys, measured elements in home tap water, and later collected naturally exfoliated teeth from child participants. We measured longitudinal deposition of elements in dentin using LA-ICP-MS. Multivariable linear mixed models were used to estimate associations between predictors and dentin element concentrations. ResultsWe measured 12 elements in dentin including those previously reported (Ba, Mn, Pb, Sr, Zn) and less frequently reported (Al, As, Cd, Cu, Hg, Li, and W). A doubling of Pb or Sr concentrations in water was associated with higher dentin Pb or Sr respectively in prenatally formed [9% (95%CI: 3%, 15%); 3% (1%, 6%)] and postnatally formed [10% (2%, 19%); 6% (2%, 10%)] dentin. Formula feeding from birth to 6 weeks or 6 weeks to 4 months was associated with higher element concentrations in postnatal dentin within the given time period as compared to exclusive human milk feeding: Sr: 6 weeks: 61% (36%, 90%) and 4 months: 85% (54%, 121%); Ba: 6 weeks: 35% (3.3%, 77%) and 4 months: 42% (10%, 83%); and Li: 6 weeks: 61% (33%, 95%) and 4 months: 58% (31%, 90%). SignificanceThese findings offer insights into predictors of dentin elements and potential confounders in exposure-health outcome relationships during critical developmental periods.