Sleep really does help when it comes to recalling memories
November 2nd, 2010 - 4:34 pm ICT by ANIWashington, Nov 2 (ANI): A new study by researchers at the University of York and Harvard Medical School suggests that sleep not only helps in learning a new piece of information, such as a new phone number or a new word, but also gets the brain to file it away so it is available when needed.
The scientists found that sleep helps people to remember a newly learned word and incorporate new vocabulary into their “mental lexicon”.
During the study, researchers taught volunteers new words in the evening, followed by an immediate test.
The volunteers slept overnight in the laboratory while their brain activity was recorded using an electroencephalogram, or EEG.
A test the following morning revealed that they could remember more words than they did immediately after learning them, and they could recognize them faster demonstrating that sleep had strengthened the new memories.
This did not occur in a control group of volunteers who were trained in the morning and re-tested in the evening, with no sleep in between.
An examination of the sleep volunteers’ brainwaves showed that deep sleep (slow-wave sleep) rather than rapid eye movement (REM) sleep or light sleep helped in strengthening the new memories.
When the researchers examined whether the new words had been integrated with existing knowledge in the mental lexicon, they discovered the involvement of a different type of activity in the sleeping brain.
Sleep spindles are brief but intense bursts of brain activity that reflect information transfer between different memory stores in the brain —
the hippocampus deep in the brain and the neocortex, the surface of the brain.
Memories in the hippocampus are stored separately from other memories, while memories in the neocortex are connected to other knowledge.
Volunteers who experienced more sleep spindles overnight were more successful in connecting the new words to the rest of the words in their mental lexicon, suggesting that the new words were communicated from the hippocampus to the neocortex during sleep.
The study has been published in the Journal of Neuroscience. (ANI)
- Sleep best way to absorb knowledge - Jan 26, 2011
- Star-shaped brain cells 'essential for making long-term memories' - Mar 04, 2011
- Brain area critical for forming unconscious memories identified - Dec 16, 2010
- Mechanism behind memory formation during sleep uncovered - Sep 16, 2009
- Brain regions can briefly go 'off-line' even while awake, causing errors - Apr 28, 2011
- Now, a computer algorithm that can record memories - Mar 12, 2010
- Managing people helps develop better brains - Sep 09, 2011
- Tickling brain part boosts memory cells - Sep 21, 2011
- Multiple channels help brain avoid traffic overload - May 07, 2012
- Children's brain development linked to physical fitness - Sep 16, 2010
- Specific changes in the brain linked to sleep deprivation - Nov 04, 2010
- Mental activity 'can protect memory of patients with multiple sclerosis' - Jun 15, 2010
- Mother's love triggers bigger brain growth - Jan 31, 2012
- Physically-fit kids have better memory - Sep 16, 2010
- Chronic brain inflammation 'linked to memory loss in older adults' - Apr 14, 2011
Tags: brain activity, control group, deep sleep, eeg, electroencephalogram, harvard medical school, hippocampus, information transfer, intense bursts, memory stores, mental lexicon, neocortex, new memories, nov 2, rapid eye movement, sleep spindles, slow wave sleep, study researchers, vocabulary, volunteers