Abstract: As an important physiological activity of individuals, sleep has an important influence on physical and mental health. Poor sleep quality is associated with chronic diseases, neurodevelopmental disorders, and psychosocial stress. It has been found that poor sleep quality is associated with lower academic performance of school-age children, but the underlying mechanisms need to be further explored. Therefore, this study attempted to explore the internal mechanism in the relationship between sleep quality and academic performance of school-age children. Based on existing studies, children with poor sleep quality perform worse in school than children with good sleep quality, and continuous poor sleep quality is associated with continued academic difficulties for children. Therefore, sleep quality is an important factor in explaining children's poor academic performance. At the same time, some studies have found that poor sleep quality will hinder the neural development of the hippocampus and the consolidation of long-term memory information, thus resulting in the poor updating ability of individuals, the bad memory of learning materials, and academic difficulties. In this study, we hypothesized that poor sleep quality in children would first lead to poor updating ability, which then may affect cognitive activities based on the updating function, such as academic activities. Therefore, we hypothesized that updating function played a mediating role in the relation between sleep quality and academic performance.
A total of 203 children (93 males and 110 females) with an average age of 10.49 years old completed all the experimental tasks. The experimental tasks involved questionnaires on children's sleep habits, digital refresh task (1750ms, 750ms), and the scores of children. Then SPSS 23.0 was used to describe and analyze the data, and Mplus 8.3 was used for path analysis of the structural equation model. The results showed that: (1) Sleep quality was negatively correlated with academic performance and updating function; while there was a significant positive correlation between updating function and academic performance. (2) Sleep quality did not directly affect academic performance. The sleep quality influenced academic performance through the updating ability. This study constructed the mediation model to explore the relationship between the sleep quality and academic performance and then verified the mediation function of the updating ability. But there are still some shortcomings. First of all, the relation between sleep quality and academic performance has yet not been tested, and future research can further explore how the subjective and objective sleep quality are associated with the standardized academic tests and academic grades rated by teachers. Secondly, this study has poor control over confounding variables. To investigate the relation between sleep quality and academic performance, future studies should control the key factors that affect children's academic performance, such as children's age, their parents' education level and learning motivation. Thirdly, the cross-sectional data of this study cannot establish a causal relationship between sleep quality and academic achievement, and more follow-up and experimental studies are needed to evaluate whether and in what way if possible the two have causal relationship. Finally, some researchers found that children's self-reported internalized and externalized mental health problems played a mediating role in the relationship between sleep quality and academic performance. Future researchers could further explore other factors through which sleep quality affects academic performance.

Key words: academic achievement, sleep quality, updating ability, school-age children

摘要： 本研究探讨了刷新能力在睡眠质量与学龄儿童学业成绩之间的中介作用。采用儿童睡眠习惯问卷、活动记忆任务和各科学业成绩对394名小学5年级儿童进行调查。研究结果发现,睡眠质量得分与学业成绩、刷新能力均呈显著负相关,刷新能力与学业成绩呈现显著正相关;刷新能力在学龄儿童睡眠质量与学业成绩间起完全中介作用。

关键词: 学业成绩, 睡眠质量, 刷新能力, 学龄儿童