Studies have shown that number line estimation is important for learning. However, it is yet unclear if number line estimation predicts different mathematical skills in different grades after controlling for age, nonverbal cognitive ability, attention, and working memory. The purpose of this study was to examine the role of number line estimation on two mathematical skills (calculation fluency and math problem-solving) in grade 2 and grade 4. One hundred and forty-eight children from Shanghai, China were assessed on measures of nonverbal cognitive ability (Nonverbal Matrices), working memory (N-back), attention (Expressive Attention), and mathematical skills (calculation fluency and math problem-solving). The results showed that in grade 2, number line estimation correlated significantly with calculation fluency (r = -.27, p < .05) and math problem-solving (r = -.52, p < .01). In grade 4, number line estimation correlated significantly with math problem-solving (r = -.38, p < .01), but not with calculation fluency. Regression analyses indicated that in grade 2, number line estimation accounted for unique variance in math problem-solving (12.0%) and calculation fluency (4.0%) after controlling for the effects of age, nonverbal cognitive ability, attention, and working memory. In grade 4, number line estimation accounted for unique variance in math problem-solving (9.0%) but not in calculation fluency. These findings suggested that number line estimation had an important role in math problem-solving for both grades 2 and 4 children and in calculation fluency for grade 2 children. We concluded that number line estimation could be a useful indicator for teachers to identify and improve children’s mathematical skills.

Mutual prediction is crucial for understanding the mediation of bodily actions in social interactions. Despite this importance, limited studies have investigated neurobehavioral patterns under the mutual prediction hypothesis in natural competitive scenarios. To address this gap, our study employed functional near-infrared spectroscopy hyperscanning to examine the dynamics of real-time rock-paper-scissors games using a computerized paradigm with 54 participants. Firstly, our results revealed activations in the right inferior frontal gyrus, bilateral dorsolateral prefrontal cortex, and bilateral frontopolar cortex, each displaying distinct temporal profiles indicative of diverse cognitive processes during the task. Subsequently, a task-related increase in inter-brain synchrony was explicitly identified in the right dorsolateral prefrontal cortex, which supported the mutual prediction hypothesis across the two brains. Moreover, our investigation uncovered a close association between the coherence value in the right dorsolateral prefrontal cortex and the dynamic predictive performances of dyads using inter-subject representational similarity analysis. Finally, heightened inter-brain synchrony values were observed in the right dorsolateral prefrontal cortex before a draw compared to a no-draw scenario in the second block, suggesting that cross-brain signal patterns could be reflected in behavioral responses during competition. In summary, these findings provided initial support for expanding the understanding of cognitive processes underpinning natural competitive engagements.

The study aimed to explore the development trend of positive mental health and the interaction between adolescents’ perceived family support and positive mental health. A 3-year longitudinal survey of perceived family support and positive mental health (resilience and self-efficacy) for four waves was conducted with 564 junior high school students (297 girls, mean age = 11.12 ± 0.38 years at baseline). The Latent Growth Curve Modeling indicated that adolescents’ resilience and general self-efficacy showed a curve upward trend, which increased first and then decreased. The development rate decreased each year. The cross-lagged panel model and a random intercept cross-lagged panel model concluded that perceived family support was strongly associated with positive mental health of junior high school students. Family support was important for developing positive mental health in early adolescence. Therefore, attention and interventions targeting positive mental health changes in early adolescence are particularly effective. And, it is important to encourage parents of adolescents to continue to provide support and guidance.