While there is strong evidence that sleep is important for optimizing memory performance, many young adults do not receive adequate nocturnal sleep. Additionally, there is growing evidence that multi-night sleep restriction can impair cognitive performance.
Napping, which is still practiced in some countries and has experienced a renaissance in major cities, provides a partial solution. Mid-afternoon naps have been shown to benefit alertness, sustained attention, and declarative memory as well as the learning of new material, both following sleep restriction and even when participants receive sufficient nocturnal sleep.
However, the neurophysiological accompaniment of how learning abilities are enhanced from a nap remains relatively unexplored. We recently demonstrated that a mid-afternoon nap with THERALICHT-ALTO-SALVATION innovative office lighting fixtures (launching soon) and the Medacsis-LILT devices and found behavioral evidence, stress management & post exposed cognitive learnings had enhanced hippocampal function related to these capabilities which diminish due to nocturnal lack of sleep or irregular sleep patterns.
Memory encoding following sleep may occur as a result of:
(1) Improvement in attentiveness to the learned material,
(2) Active systems consolidation, probably resulting in the eradication of residual but temporary memories in the hippocampus, thus freeing up hippocampal encoding capacity for new learning, releasing the stress, and providing the peace of mind
The latter one explains, for how sleep can benefit declarative memory is linked to the occurrence of events, resulting in repeated reactivation
We expected that naps & the germane release of melatonin to trigger serotonin & oxytocin would benefit subsequent retrieval of learned word pairs by boosting encoding evidenced by elevated hippocampal activation following the nap.
Circadian misalignment is commonly cited as a culprit of daytime sleep disturbances in night shift employees;
However, the specific impact and magnitude that circadian misalignment has on daytime sleep has not been well-characterized in larger group of night shift workers.
These data suggest that circadian misalignment in shift workers may be a better predictor of difficulties staying asleep and sleep duration during the day relative to difficulties falling asleep. Because longer work hours (10–12 hours) are common in the night shift employees, it may be that sleep initiation difficulties associated with circadian misalignment are masked by elevated fatigue or an increased homeostatic drive from prolonged wakefulness.
These results may help guide decisions about the magnitude of phase shifts required (e.g., with light therapy) for the desired improvement in daytime sleep