These findings suggest an earlier onset of brain maturation in girls, reflected by less deep sleep, faster sleep spindles, frontal shift in delta power, and greater cortical excitability during wakefulness, challenging the notion that developmental modifications of sleep are minimal during childhood.
N3 (slow-wave sleep) and REM sleep durations decreased with age in girls but not in boys.
Sleep spindle frequency during N2 sleep increased with age in girls but not in boys.
Delta power topography shifted from posterior to anterior brain regions in girls compared to boys.
Girls exhibited greater cortical excitability during wakefulness as evidenced by a reduction in resting EEG slope.
Overnight memory consolidation did not vary with age or gender.
The study design involved home-based polysomnography combined with pre- and post-sleep cognitive testing in 61 children aged 5-12.
This research suggests that the brains of girls and boys develop along different timelines during childhood, and that these differences are visible in how they sleep. In a study of 61 children aged 5 to 12, researchers recorded brain activity overnight at home and measured attention and memory before and after sleep. They found that girls showed several signs of earlier brain maturation: they had less deep sleep and less REM sleep as they got older, their sleep spindles (brief bursts of brain activity during sleep thought to be important for learning) became faster with age, the location of slow brain waves shifted toward the front of the brain, and their brains appeared more active and excitable during waking hours. None of these age-related patterns were observed in boys during this same age window. One practical implication is that faster sleep spindles in girls were linked to better attention performance the morning after sleep, suggesting the maturing sleep brain may support cognitive functioning differently in girls and boys. Interestingly, memory consolidation overnight — how well children remembered information learned before sleep — did not differ by age or gender, suggesting that at least some sleep-related cognitive benefits are relatively stable across this developmental window. This research suggests that the common assumption that sleep changes very little during childhood may need to be reconsidered, at least for girls. The findings point toward puberty or its timing as a possible driver of these differences, though the study was cross-sectional and could not directly test this. Future longitudinal studies tracking the same children over time will be needed to understand how these sleep and brain maturation changes unfold and whether they are tied to the timing of puberty.
Mammeri K, Legendre G, Journal F, Fernandez N, Ruppen-Maret H, Combey J, et al.. (2026). Age and gender-related neurophysiological changes in sleep and wake states during childhood.. Developmental cognitive neuroscience. https://doi.org/10.1016/j.dcn.2026.101681