Napping restores working memory and brain activation impaired by sleep deprivation.

BACKGROUND

Sleep deprivation (SD) impairs working memory (WM), yet the restorative potential of brief daytime naps remains underexplored. This study examines how naps counteract SD-induced WM deficits through behavioral and neuroimaging mechanisms, focusing on task-positive networks and default mode network (DMN) dynamics.

METHOD: A within-subject fMRI study employed 2-back WM tasks in 50 participants under three conditions: baseline wakefulness, post-30h SD, and post-nap recovery. Behavioral metrics (reaction times, accuracy) and fMRI activation patterns were analyzed using repeated-measures ANOVA and mixed-effects models to assess SD and nap effects.

RESULT: Naps partially restored SD-induced WM declines, improving reaction times and accuracy. Post-SD, reduced activation in the cerebellum, insula, and thalamus (attention/executive regions) rebounded post-nap. SD weakened DMN suppression (middle frontal gyrus, precuneus, superior temporal gyrus), with maximal DMN suppression post-nap. Improved WM performance correlated with reactivated task-positive networks.

CONCLUSION

Daytime naps mitigate SD-related WM deficits by rebalancing task-positive network activation (cerebellum, thalamus) and enhancing DMN suppression. These findings elucidate neurophysiological mechanisms of sleep-cognition interactions, supporting naps as a practical intervention for SD-induced cognitive impairment.