The Nature team were keen to know more about our new research article: "Post-class naps boost declarative learning in a naturalistic school setting” published in their journal npj Science of Learning. My colleagues, Thiago Cabral, Natalia Mota, Lucia Fraga, Mauro Copelli, Mark McDaniel and myself are based at the Universidade Federal do Rio Grande do Norte in Brazil, South America. We are more than happy to discuss why integrating sleep time with school curriculum can benefit students learning through the following responses.
What is your area of interest within the science of learning?
Our research in this field focuses on the cognitive benefits of post-class naps in the school environment, and the use of word graphs to probe language development and academic achievement.
What was the main aim of your research and why did you decide to investigate this?
The main aim of our study was to assess whether a naturalistic use of post-class naps, with minimal changes to the students' school routines, would still show the academic benefits that are observed under more artificial, laboratory-like conditions, such as improvement in performance resulting from an external influence. This is an important topic of research because post-class sleep represents a potential game-changer for formal education, particularly in countries or communities with low socio-economic status (SES) where children often lag behind their cohort due to physiological handicaps produced by sleep debt (or sleep deprivation).
What were the key findings from the study?
Long morning naps (30 to 60 minutes) significantly increased memory retention of curricular contents by approximately 10 per cent. However, shorter naps (less than 30 minutes duration) showed no effect. Importantly, the results were obtained with a rigorous design, where participants experienced the treatment at different times during a randomised schedule each week, which strengthened the validity of the results.
How do post-class naps complement the aims of a naturalist school program?
Children in populous countries such as Brazil, the USA and China often start school very early, and as a result, there is a large prevalence of sleep debt. The school use of post-class morning naps for older children, such as those in our study (and not just for toddlers), which normally have no opportunity to sleep during the day, may transform the physiological handicap of sleep deprivation into a cognitive benefit, with increased consolidation of declarative memories due to the coordination of classes with nap times. In other words, academic benefits may be derived for students disadvantaged by their socio-economic situation, by making smart use of sleep in the school setting. Our results indicated that, rather than fighting the physiological drive to nap, teachers should allow sleep to do its job, creating synergy between physiology and teaching.
Do you think more schools should adopt this strategy to assist students learning?
Yes, because it has low cost, is relatively easy to implement and produces reliable academic gains. We also raise the possibility the cognitive benefits of post-learning naps may grow like compound interest. This possibility is yet to be tested, using long-term experimental designs.
What’s the bigger picture of your research findings?
Household overcrowding and poor sleep habits commonly experienced by low SES communities produce deficits in nutrition, sleep, and exercise that hamper overall physiology (or physical health), greatly decreasing an affected child's capacity to learn. In low SES countries with stark educational inequality, important academic benefits are expected to result from surmounting these physiological bottlenecks, ‘‘low-hanging fruit’’ that should be picked sooner than later by the implementation of public policy. The reason is that, in poverty, education must first focus on solving the physiological handicap, and only after that the efforts to improve teaching/learning methods can be successful. The cyclic alternation of eating, sleeping, exercising and attending classes is likely to optimize learning and decrease educational gradients in student’s results.
What next? What further research is needed in this area?
There are at least three immediate fronts, the first two extensive and the last one intensive: 1) to replicate the experiment on a very large scale, with thousands of children in multiple schools, to assess scalability; 2) to replicate the experiment for an entire year instead of 6 weeks, to assess the possibility that nap-related academic gains may grow like compound interest; and 3) to replicate the experiment on a small scale but with one portable EEG device per student, to establish which sleep phase and specific brain waves are most beneficial for school learning. These three fronts should allow for optimization and personalization of the intervention.