Lacking scientific understanding of the function of naps in early childhood, policy makers may curtail preschool classroom nap opportunities due to increasing curriculum demands. Here Kurdziel and colleagues show evidence that classroom naps support learning in preschool children by enhancing memories acquired earlier in the day compared with equivalent intervals spent awake. Performance losses when nap-deprived were not recovered during subsequent overnight sleep. Physiological recordings supported a role for sleep spindles in memory performance. Sleep spindles are bursts of oscillatory brain activity visible on an EEG that occur during stage 2 sleep. The authors suggest that distributed sleep is critical in early learning and that when short-term memory stores are limited, memory consolidation must take place frequently.
Kurdziel L, Duclos K, and Spencer RMC: Sleep spindles in midday naps enhance learning in preschool children. Proc. Natl. Acad. Sci. USA110(43): 17267-17272 (2013).