Recent onderzoek toont nu ook aan dat een volwassenen die een middagdutje doen, nadien beter in staat zijn om nieuwe zaken te leren, dan volwassenen die geen middagdutje deden.
Nieuwe info zou eerst kortstondig worden opgeslagen in de hippocampus, die dienst doet als korte termijn geheugen (KTG). Deze info wordt dan later opgeslagen in de prefrontale cortex (= het lange termijn geheugen).
Vooral in de 2de fase van de slaap/ middagdutje wordt de hippocampus ahw. 'geleegd' zodat er weer ruimte is voor nieuwe info. Zolang dit niet gebeurd, zit de hippocampus (KTG) ahw. vol waardoor er geen nieuwe info kan worden opgenomen.
uit: University of California - Berkeley (2010, February 22). Midday nap markedly boosts the brain's learning capacity. ScienceDaily.
...The results support previous data from the same research team that pulling an all-nighter -- a common practice at college during midterms and finals -- decreases the ability to cram in new facts by nearly 40 percent, due to a shutdown of brain regions during sleep deprivation.
In the recent UC Berkeley sleep study, 39 healthy young adults were divided into two groups -- nap and no-nap. At noon, all the participants were subjected to a rigorous learning task intended to tax the hippocampus, a region of the brain that helps store fact-based memories. Both groups performed at comparable levels.
At 2 p.m., the nap group took a 90-minute siesta while the no-nap group stayed awake. Later that day, at 6 p.m., participants performed a new round of learning exercises. Those who remained awake throughout the day became worse at learning. In contrast, those who napped did markedly better and actually improved in their capacity to learn.
These findings reinforce the researchers' hypothesis that sleep is needed to clear the brain's short-term memory storage and make room for new information,
"It's as though the e-mail inbox in your hippocampus is full and, until you sleep and clear out those fact e-mails, you're not going to receive any more mail. It's just going to bounce until you sleep and move it into another folder," Walker said.
In the latest study, Walker and his team have broken new ground in discovering that this memory- refreshing process occurs when nappers are engaged in a specific stage of sleep. Electroencephalogram tests, which measure electrical activity in the brain, indicated that this refreshing of memory capacity is related to Stage 2 non-REM sleep, which takes place between deep sleep (non-REM) and the dream state known as Rapid Eye Movement (REM).