Proper sleep can sharpen your memory

External spur during sleep can help reinforce memory, which, in turn, can help you learn, a new study reports.

Researchers from Northwestern University noted that such stimulation could emphasize what people have already learnt, but doesn’t help them gain new skills.

“The critical difference is that our study shows that memory is strengthened for something you’ve already learned,” the study’s co-author, Paul Reber, associate professor of psychology at Northwestern, said in a university news release. “Rather than learning something new in your sleep, we’re talking about enhancing an obtainable memory by reactivating information recently acquired.”

In conducting the study, researchers trained participants how to play two musical tunes by pressing certain keys at certain times. After they learned how to play the unnaturally generated tunes, the participants took a 90-minute nap. While they slept, only one of the songs was played. The soft musical cues, the researchers noted, were played during slow-wave sleep, a period of sleep that is linked to storing memories.

As the participants napped, the researchers recorded their electrical brain activity using electroencephalography. After they woke up, the participants made smaller amount mistakes when playing the tune that was played while they were sleeping than the one that was not played.

“Our results extend prior research by viewing that external stimulation during sleep can influence a complex skill,” the study’s elder author, Ken Paller, professor of psychology in the Weinberg College of Arts and Sciences at Northwestern, said in the news release.

“We also found that electrophysiological signals during sleep connected with the extent to which memory improved,” additional lead author James Antony, of the Interdepartmental Neuroscience Program at Northwestern. “These signals may thus be measuring the brain events that produce memory development during sleep.”

The researchers said they are investigating how their result could possibly be applied to other types of learning, such as studying a foreign language. They noted their study could also lead to more studies on sleep-based memory-processing involving other types of skills, practice and behaviors.

Scientists make use of cloning to Make Human Stem Cells

U.S. scientists for the first time have used a cloning technique to get tailor-made embryonic stem cells to produce in unfertilized human egg cells, a landmark decision and a potential new flashpoint for opponents of stem cell research.

The researchers were trying to confirm whether it is possible to use a cloning technology called somatic cell nuclear transfer, or SCNT, to compose embryonic stem cells that equal a patient’s DNA.

The achievement, published on Wednesday in the journal Nature, is significant because such patient-specific cells potentially can be transplanted to replace smashed cells in people with diabetes and other diseases without denunciation by the immune system.

This technique could ignite new controversy because some opponents consider it to be cloning, which they severely oppose.

“This paper will be seen as significant both by those who are demanding to use SCNT to produce human patient-specific embryonic stem cell lines and by those who oppose human ‘cloning’ experiments,” said Professor Robin Lovell-Badge, a division head at Britain’s National Institute for Medical Research.

Stem cells are the body’s master cells, the supply material for all other cells. Proponents of embryonic stem cells say they could transform medicine, providing treatments for blindness, juvenile diabetes or harsh injuries.

Normally, SCNT involves removing genetic material from the nucleus of the host egg cell and replacing it with the nucleus from adult cells, the system used to clone animals such as Dolly the sheep in 1996. But scientists so far have failed to get these cells to grow and divide beyond a very premature stage in humans and non-human primates.

Scientists in this cram, led by Dieter Egli and Scott Noggle at The New York Stem Cell Foundation Laboratory in New York, kept the genetic material from the host egg and minimally added the nucleus from the mature cells.