Preliminary exploration of a multidimensional sleep health composite in adolescent females with frequent migraine.

OBJECTIVE: This observational study aimed to: (i) describe and explore preliminary psychometric properties of a multidimensional sleep health composite score in adolescent females with frequent migraine; and (ii) examine associations between the composite score, headache characteristics, and emotional health. BACKGROUND: Sleep health is a multidimensional construct comprised of various dimensions of sleep and circadian functioning, including Regularity, Satisfaction, Alertness, Timing, Efficiency, and Duration (Ru-SATED framework). The Ru-SATED sleep health composite score may provide a holistic perspective of sleep among adolescents with frequent migraine in the context of neurobiological and psychosocial impacts on sleep unique to this developmental period. METHODS: In all, 60 female adolescents (aged 12-18 years) with high-frequency episodic or chronic migraine completed wrist-worn actigraphy for 10 days and concurrent daily electronic surveys assessing headache, sleep, and emotional health. A sleep health composite score was derived from empirically supported "healthy" versus "unhealthy" ratings on the six Ru-SATED sleep dimensions. RESULTS: Half of participants (27/54 [50%]) had a composite score ≥4 (i.e., at least four of the six dimensions rated as poor). Convergent validity of the composite score was acceptable (rs = 0.30-0.56, all p < 0.05). Internal consistency among the dimensions was low (α = 0.45). Multivariate multiple regression models indicated that worse sleep health was associated with greater headache-related disability (B = 0.71, p = 0.018) and anxiety (B = 0.59, p = 0.010), and trended toward significance for sadness (B = 0.35, p = 0.052). The composite score was not significantly associated with headache frequency or severity. CONCLUSIONS: A multidimensional sleep health composite score may provide an alternative, more comprehensive picture of sleep disturbance among adolescent females with frequent migraine. Larger studies are needed to examine psychometric properties more rigorously and further explore the composite score as a potentially unique predictor of headache outcomes.

Brain network modularity predicts changes in cortical thickness in children involved in a physical activity intervention.

Individual differences in brain network modularity at baseline can predict improvements in cognitive performance after cognitive and physical interventions. This study is the first to explore whether brain network modularity predicts changes in cortical brain structure in 8- to 9-year-old children involved in an after-school physical activity intervention (N = 62), relative to children randomized to a wait-list control group (N = 53). For children involved in the physical activity intervention, brain network modularity at baseline predicted greater decreases in cortical thickness in the anterior frontal cortex and parahippocampus. Further, for children involved in the physical activity intervention, greater decrease in cortical thickness was associated with improvements in cognitive efficiency. The relationships among baseline modularity, changes in cortical thickness, and changes in cognitive performance were not present in the wait-list control group. Our exploratory study has promising implications for the understanding of brain network modularity as a biomarker of intervention-related improvements with physical activity.

Brain Network Modularity Predicts Improvements in Cognitive and Scholastic Performance in Children Involved in a Physical Activity Intervention.

Introduction: Brain network modularity is a principle that quantifies the degree to which functional brain networks are divided into subnetworks. Higher modularity reflects a greater number of within-module connections and fewer connections between modules, and a highly modular brain is often interpreted as a brain that contains highly specialized brain networks with less integration between networks. Recent work in younger and older adults has demonstrated that individual differences in brain network modularity at baseline can predict improvements in performance after cognitive and physical interventions. The use of brain network modularity as a predictor of training outcomes has not yet been examined in children. Method: In the present study, we examined the relationship between baseline brain network modularity and changes (post-intervention performance minus pre-intervention performance) in cognitive and academic performance in 8- to 9-year-old children who participated in an after-school physical activity intervention for 9 months (N = 78) as well as in children in a wait-list control group (N = 72). Results: In children involved in the after-school physical activity intervention, higher modularity of brain networks at baseline predicted greater improvements in cognitive performance for tasks of executive function, cognitive efficiency, and mathematics achievement. There were no associations between baseline brain network modularity and performance changes in the wait-list control group. Discussion: Our study has implications for biomarkers of cognitive plasticity in children. Understanding predictors of cognitive performance and academic progress during child development may facilitate the effectiveness of interventions aimed to improve cognitive and brain health.

Scholastic performance and functional connectivity of brain networks in children.

One of the keys to understanding scholastic success is to determine the neural processes involved in school performance. The present study is the first to use a whole-brain connectivity approach to explore whether functional connectivity of resting state brain networks is associated with scholastic performance in seventy-four 7- to 9-year-old children. We demonstrate that children with higher scholastic performance across reading, math and language have more integrated and interconnected resting state networks, specifically the default mode network, salience network, and frontoparietal network. To add specificity, core regions of the dorsal attention and visual networks did not relate to scholastic performance. The results extend the cognitive role of brain networks in children as well as suggest the importance of network connectivity in scholastic success.

Physical Activity Increases White Matter Microstructure in Children.

Children are becoming increasingly inactive, unfit, and overweight, yet there is relatively little causal evidence regarding the effects of physical activity on brain health during childhood. The present study examined the effects of an after-school physical activity program (FITKids2) on the microstructure of white matter tracts in 7- to 9-year-old children. We measured the microstructural properties of white matter via diffusion tensor imaging in 143 children before and after random assignment to either a 9-month after-school physical activity program (N = 76, mean age = 8.7 years) or a wait list control group (N = 67, mean age = 8.7 years). Our results demonstrate that children who participated in the physical activity program showed increased white matter microstructure in the genu of the corpus callosum, with no changes in white matter microstructure in the wait list control group which reflects typical development. Specifically, children in the physical activity program showed increases in fractional anisotropy (FA) and decreases in radial diffusivity (RD) in the genu from pre- to post-test, thereby suggesting more tightly bundled and structurally compact fibers (FA) and increased myelination (RD), with no changes in estimates of axonal fiber diameter (axial diffusivity, AD). The corpus callosum integrates cognitive, motor, and sensory information between the left and right hemispheres of the brain, and the white matter tract plays a role in cognition and behavior. Our findings reinforce the importance of physical activity for brain health during child development.

Aerobic fitness is associated with greater hippocampal cerebral blood flow in children.

The present study is the first to investigate whether cerebral blood flow in the hippocampus relates to aerobic fitness in children. In particular, we used arterial spin labeling (ASL) perfusion MRI to provide a quantitative measure of blood flow in the hippocampus in 73 7- to 9-year-old preadolescent children. Indeed, aerobic fitness was found to relate to greater perfusion in the hippocampus, independent of age, sex, and hippocampal volume. Such results suggest improved microcirculation and cerebral vasculature in preadolescent children with higher levels of aerobic fitness. Further, aerobic fitness may influence how the brain regulates its metabolic demands via blood flow in a region of the brain important for learning and memory. To add specificity to the relationship of fitness to the hippocampus, we demonstrate no significant association between aerobic fitness and cerebral blood flow in the brainstem. Our results reinforce the importance of aerobic fitness during a critical period of child development.

Correction: The Role of Aerobic Fitness in Cortical Thickness and Mathematics Achievement in Preadolescent Children.

[This corrects the article DOI: 10.1371/journal.pone.0134115.].

The role of aerobic fitness in cortical thickness and mathematics achievement in preadolescent children.

Growing evidence suggests that aerobic fitness benefits the brain and cognition during childhood. The present study is the first to explore cortical brain structure of higher fit and lower fit 9- and 10-year-old children, and how aerobic fitness and cortical thickness relate to academic achievement. We demonstrate that higher fit children (>70th percentile VO2max) showed decreased gray matter thickness in superior frontal cortex, superior temporal areas, and lateral occipital cortex, coupled with better mathematics achievement, compared to lower fit children (<30th percentile VO2max). Furthermore, cortical gray matter thinning in anterior and superior frontal areas was associated with superior arithmetic performance. Together, these data add to our knowledge of the biological markers of school achievement, particularly mathematics achievement, and raise the possibility that individual differences in aerobic fitness play an important role in cortical gray matter thinning during brain maturation. The establishment of predictors of academic performance is key to helping educators focus on interventions to maximize learning and success across the lifespan.