The braincherry-pickswhat people remember during sleep,resulting insharper and clearer thinking, a new study suggests.
Previousresearch had shown that sleep helps peopleconsolidatetheir memories,fixingthem in the brain so we canretrievethem later.
But the new study, areviewbased on new studies as well as past research on sleep and memory, suggests that sleep also transforms memories in ways that make them somewhat lessaccuratebut more usefulin the long run.
For example, sleep-enabled memories may help peopleproduceinsight, draw , andinferencesfosterabstractthought during waking hours.
"The sleeping brain isn't stupid—it doesn't just consolidate everything you put into it, but calculates what to remember and what to forget," said study leader Jessica Payne, acognitiveneuroscientist at the University of Notre Dame in Indiana.
Emotional Memories Stick
For instance, the memory details thatseemto get remembered best are often the most emotional ones, Payne said.
Payne andcolleaguesfound that when people are shown ascenewith an emotion-ladenobject in theforeground—such as awreckedcar—they are morelikelyto remember that object than, say, palm trees in the background, especially if they are tested after a night ofslumber.
Rather thanpreserving scenes in theirentirety, the brainapparentlyrestructures scenes to remember only their most emotional and perhaps most important elements while allowing less emotional details todeteriorate.
Measurements of brain activity support thisnotion, revealing that brain regions linked with emotion and memory consolidation are more periodically active during sleep then when awake.
"Itmakes senseto selectively remember emotional information—ourancestorswould not want to forget a snake was in aparticularlocation or that someone in thetribewas particularlymeanand should be avoided," said Payne, whose study appeared in the Octoberissueof the journal Current Directions in Psychological Science.
"Memories are not so much about remembering the past as being able toanticipateandpredictmultiple possible futures."
Selective Memory's Dark Side
But there are dark sides to suchselectivity. For instance, the brain can focus on remembering negative experiences at theexclusionof others, which occurs in depression and post-traumatic stressdisorder.
Future research mayshedlight on what details are remembered and how they're remembered, which could helpdeal withtrauma, Payne noted.
"You could also see such work being helpful in coming up with solutions in the classroom or in the business world," she said.
Future research may also reveal what components of sleep might be linked with these mental processes.
"Does it require the REM sleep associated with dreaming, or deeper slow-wave sleep?" said Robert Stickgold, a cognitive neuroscientist at Harvard Medical School who researches sleep.
Overall, "sleep is doing much morecomplicatedstuff than juststabilizingorstrengtheningmemories," Stickgold added.
Uykuda anılar seçiliyor, zekiliği artırıyor - Sleep Cherry-picks Memories, Boosts Cleverness
The braincherry-pickswhat people remember during sleep,resulting insharper and clearer thinking, a new study suggests.
Previousresearch had shown that sleep helps peopleconsolidatetheir memories,fixingthem in the brain so we canretrievethem later.
But the new study, areviewbased on new studies as well as past research on sleep and memory, suggests that sleep also transforms memories in ways that make them somewhat lessaccuratebut more usefulin the long run.
For example, sleep-enabled memories may help peopleproduceinsight, draw , andinferencesfosterabstractthought during waking hours.
"The sleeping brain isn't stupid—it doesn't just consolidate everything you put into it, but calculates what to remember and what to forget," said study leader Jessica Payne, acognitiveneuroscientist at the University of Notre Dame in Indiana.
Emotional Memories Stick
For instance, the memory details thatseemto get remembered best are often the most emotional ones, Payne said.
Payne andcolleaguesfound that when people are shown ascenewith an emotion-ladenobject in theforeground—such as awreckedcar—they are morelikelyto remember that object than, say, palm trees in the background, especially if they are tested after a night ofslumber.
Rather thanpreserving scenes in theirentirety, the brainapparentlyrestructures scenes to remember only their most emotional and perhaps most important elements while allowing less emotional details todeteriorate.
Measurements of brain activity support thisnotion, revealing that brain regions linked with emotion and memory consolidation are more periodically active during sleep then when awake.
"Itmakes senseto selectively remember emotional information—ourancestorswould not want to forget a snake was in aparticularlocation or that someone in thetribewas particularlymeanand should be avoided," said Payne, whose study appeared in the Octoberissueof the journal Current Directions in Psychological Science.
"Memories are not so much about remembering the past as being able toanticipateandpredictmultiple possible futures."
Selective Memory's Dark Side
But there are dark sides to suchselectivity. For instance, the brain can focus on remembering negative experiences at theexclusionof others, which occurs in depression and post-traumatic stressdisorder.
Future research mayshedlight on what details are remembered and how they're remembered, which could helpdeal withtrauma, Payne noted.
"You could also see such work being helpful in coming up with solutions in the classroom or in the business world," she said.
Future research may also reveal what components of sleep might be linked with these mental processes.
"Does it require the REM sleep associated with dreaming, or deeper slow-wave sleep?" said Robert Stickgold, a cognitive neuroscientist at Harvard Medical School who researches sleep.
Overall, "sleep is doing much morecomplicatedstuff than juststabilizingorstrengtheningmemories," Stickgold added.
http://news.nationalgeographic.com/news/2010/12/101201-sleep-memories-health-brain-science/