Developmental Change of Yolk Microbiota and Its Role on Early Colonization of Intestinal Microbiota in Chicken Embryo

Although the fertilized eggs were found to contain microbes in early studies, the detailed composition of yolk microbiota and its influence on embryo intestinal microbiota have not been satisfactorily examined yet. In this study, the yolk microbiota was explored by using 16s rRNA sequencing at different developmental stages of the broiler embryo. The results showed that the relative abundance of yolk microbiota was barely changed during embryogenesis. According to the KEGG analysis, the yolk microbiota were functionally related to amino acid, carbohydrate, and lipid metabolisms during chicken embryogenesis. The yolk microbiota influences the embryonic intestinal microbiota through increasing the colonization of Proteobacteria, Firmicutes, and Bacteroidetes in the intestine, particularly. The intestinal microbes of neonatal chicks showed higher proportions of Faecalibacterium, Blautia, Coprococcus, Dorea, and Roseburia compared to the embryonic intestinal microbiota. Our findings might give a better understanding of the composition and developmental change of yolk microbiota and its roles in shaping the intestinal microbiota.

Conceptualizing and Measuring Appetite Self-Regulation Phenotypes and Trajectories in Childhood: A Review of Person-Centered Strategies

This review uses person-centered research and data analysis strategies to discuss the conceptualization and measurement of appetite self-regulation (ASR) phenotypes and trajectories in childhood (from infancy to about ages 6 or 7 years). Research that is person-centered provides strategies that increase the possibilities for investigating ASR phenotypes. We first examine the utility of examining underlying phenotypes using latent profile/class analysis drawing on cross-sectional data. The use of trajectory analysis to investigate developmental change is then discussed, with attention to phenotypes using trajectories of individual behaviors as well as phenotypes based on multi-trajectory modeling. Data analysis strategies and measurement approaches from recent examples of these person-centered approaches to the conceptualization and investigation of appetite self-regulation and its development in childhood are examined. Where relevant, examples from older children as well as developmental, clinical and educational psychology are drawn on to discuss when and how person-centered approaches can be used. We argue that there is scope to incorporate recent advances in biological and psychoneurological knowledge about appetite self-regulation as well as fundamental processes in the development of general self-regulation to enhance the examination of phenotypes and their trajectories across childhood (and beyond). The discussion and conclusion suggest directions for future research and highlight the potential of person-centered approaches to progress knowledge about the development of appetite self-regulation in childhood.

The Elusive “Developmental Mechanism”: What they are and how to study and test them

Few issues have garnered as much attention as that of understanding mechanisms of developmental change. Understanding mechanisms of developmental change is important because it allows researchers to go beyond studying at what age an ability emerges to understanding the processes by which those abilities develop in the first place. Despite the clear importance of mechanisms, the notion of a developmental mechanism or mechanism of developmental change remains largely undefined and there exists no clear guidance on how to study these mechanisms systematically in the developmental literature. Given these outstanding questions, this paper has two main aims. The first aim was to provide a clear definition of mechanisms of developmental change that aligns most closely with how most, if not all, developmental psychologists think about developmental mechanisms. The second goal was to provide concrete suggestions for how developmental scientists might study and test different kinds of mechanisms of developmental change based on their perceived manipulability. One of the main arguments of the paper is that there is no one-size-fits-all approach to studying and testing mechanisms of developmental change and that how developmental researchers study them depends crucially on their perceived manipulability.

Interactive Development of Adaptive Learning and Memory

Across development, interactions between value-based learning and memory processes promote the formation of mental models that enable flexible goal pursuit. Value cues in the environment signal information that may be useful to prioritize in memory; these prioritized memories in turn form the foundation of structured knowledge representations that guide subsequent learning. Critically, neural and cognitive component processes of learning and memory undergo marked shifts from infancy to adulthood, leading to developmental change in the construction of mental models and how they are used to guide goal-directed behavior. This review explores how changes in reciprocal interactions between value-based learning and memory influence adaptive behavior across development and highlights avenues for future research.

Developmental change in children’s speech processing of auditory and visual cues: An eyetracking study

This study investigates how children aged two to eight years (N = 129) and adults (N = 29) use auditory and visual speech for word recognition. The goal was to bridge the gap between apparent successes of visual speech processing in young children in visual-looking tasks, with apparent difficulties of speech processing in older children from explicit behavioural measures. Participants were presented with familiar words in audio-visual (AV), audio-only (A-only) or visual-only (V-only) speech modalities, then presented with target and distractor images, and looking to targets was measured. Adults showed high accuracy, with slightly less target-image looking in the V-only modality. Developmentally, looking was above chance for both AV and A-only modalities, but not in the V-only modality until 6 years of age (earlier on /k/-initial words). Flexible use of visual cues for lexical access develops throughout childhood.

As Time Goes By: Effects of Basal Chronotype and School Timing on Chronotype Development During Adolescence

The misalignment between late chronotypes and early school start times affect health, performance and psychological well-being of adolescents. Here we test whether, and how, the basal chronotype (i.e. chronotype at the beginning of secondary school) and the school timing affect the magnitude and the direction of the developmental change in chronotype during adolescence. We evaluated a sample of Argentinian students (n=259) who were randomly assigned to attend school in the morning (07:45am-12:05pm), afternoon (12:40pm-05:00pm) or evening (05:20pm-09:40pm) school timings. Importantly, chronotype and sleep habits were assessed longitudinally in the same group of students along secondary school (at 13-14 y.o. and 17-18 y.o.). Our results show that: (1) although chronotypes partially align with class time, this effect is insufficient to fully account for the differences observed in sleep-related variables between school timings; (2) both school timing and basal chronotype independently affect the direction and the magnitude of chronotype change, with greater delays associated with earlier basal chronotypes and later school timings. The practical implications of these results are challenging and should be considered in the design of future educational timing policies to improve adolescents’ well-being.

Translating RDoC to real-world impact in developmental psychopathology: A neurodevelopmental framework for application of mental health risk calculators

The National Institute of Mental Health's Research Domain Criteria (RDoC) framework has prompted a paradigm shift from categorical psychiatric disorders to considering multiple levels of vulnerability for probabilistic risk of disorder. However, the lack of neurodevelopmentally based tools for clinical decision making has limited the real-world impact of the RDoC. Integration with developmental psychopathology principles and statistical methods actualize the clinical implementation of RDoC to inform neurodevelopmental risk. In this conceptual paper, we introduce the probabilistic mental health risk calculator as an innovation for such translation and lay out a research agenda for generating an RDoC- and developmentally informed paradigm that could be applied to predict a range of developmental psychopathologies from early childhood to young adulthood. We discuss methods that weigh the incremental utility for prediction based on intensity and burden of assessment, the addition of developmental change patterns, considerations for assessing outcomes, and integrative data approaches. Throughout, we illustrate the risk calculator approach with different neurodevelopmental pathways and phenotypes. Finally, we discuss real-world implementation of these methods for improving early identification and prevention of developmental psychopathology. We propose that mental health risk calculators can build a needed bridge between the RDoC multiple units of analysis and developmental science.

Problem-Drinking Across the Lifespan: Cross-Sectional Versus Longitudinal Effects Among Midlife and Older Adults

When considering problem drinking from a lifespan-developmental perspective, an often-stated premise is that problem drinking escalates during adolescence, peaks around early young adulthood, and then declines throughout the remainder of the lifespan. However, while there is a strong empirical basis for such changes throughout adolescence and young adulthood, the notion of continued declines throughout midlife and older adulthood is less firmly established and based primarily on cross-sectional data. Thus, this study contrasted cross-sectional versus longitudinal age effects on problem-drinking changes across the lifespan, with particular focus on midlife and older adulthood. Analyses used data from a large, two-wave, U.S.-representative sample. We generated descriptive “porcupine figures” graphically depicting both cross-sectional and longitudinal age effects simultaneously, and we estimated mixed-ANOVAs to partition, test, and contrast cross-sectional versus longitudinal age effects. As expected, analyses confirmed the well-known rise and fall of problem drinking across young adulthood in both cross-sectional and longitudinal age effects. In contrast, in midlife and older adulthood, only cross-sectional age effects were consistent with the notion of continued age-related declines throughout these ages, whereas the longitudinal data showed a mixture of stability and escalation at these ages. Age-confounded cohort effects are one plausible explanation for how cross-sectional data can lead to spurious conclusions about developmental change. By potentially yielding a more accurate understanding of lifespan-developmental change in midlife and older adulthood, findings like ours could help guide lifespan-developmentally-informed interventions for midlife and older-adult problem drinkers; an objective of increasing importance in light of the ongoing aging of the U.S. population.

Using child-friendly movie stimuli to study the development of face, place, and object regions from age 3 to 12 years

Scanning young children while watching short, engaging, commercially-produced movies has emerged as a promising approach for increasing data retention and quality. Movie stimuli also evoke a richer variety of cognitive processes than traditional experiments - allowing the study of multiple aspects of brain development simultaneously. However, because these stimuli are uncontrolled, it is unclear how effectively distinct profiles of brain activity can be distinguished from the resulting data. Here we develop an approach for identifying multiple distinct subject-specific Regions of Interest (ssROIs) using fMRI data collected during movie-viewing. We focused on the test case of higher-level visual regions selective for faces, scenes, and objects. Adults (N=13) were scanned while viewing a 5.5 minute child-friendly movie, as well as a traditional experiment with isolated faces, scenes, and objects. We found that just 2.7 minutes of movie data could identify subject-specific face, scene, and object regions. While successful, the movie approach was still less effective than a traditional localizer. Having validated our approach in adults, we then used the same methods on movie data collected from 3-12-year-old children (N=122). Movie response timecourses in 3-year-old childrens face, scene, and object regions were already significantly and specifically predicted by timecourses from the corresponding regions in adults. We also found evidence of continued developmental change, particularly in the face-selective posterior superior temporal sulcus. Taken together, our results reveal both early maturity and functional change in face, scene, and object regions, and more broadly highlight the promise of short, child-friendly movies for developmental cognitive neuroscience.