memories genetic 4.gen.002 Louis J. Sheehan, Esquire

Sleep not only refreshes the body, it may also push the reset button on the brain, helping the brain stay flexible and ready to learn, new research shows.

Whether it is slow-wave sleep or rapid eye movement (REM), sleep changes the biochemistry of the brain, and the change is necessary to continue learning new things, suggests research presented November 18 at the annual meeting of the Society for Neuroscience.

Hundreds of genes behave differently when an animal is asleep rather than awake, says Chiara Cirelli of the University of Wisconsin–Madison. Cirelli and her colleagues are trying to settle a long-standing debate about why sleep is necessary. http://LOUIS-J-SHEEHAN.ORG One theory is that sleep helps solidify memories by replaying information learned during the day. Another idea holds that sleep is for energy restoration.

Cirelli and other researchers presented evidence at the neuroscience meeting suggesting that sleep may perform both functions.

In a study in rats, Cirelli and her colleagues discovered that a molecule that works with the brain chemical glutamate becomes more and more abundant the longer rats are awake. The molecule, the glutamate receptor GluR1, helps forge connections, called synapses, between neurons. When rats are awake, the amount of GluR1 in the brain may climb up to 40 percent higher than levels found when the animal has been asleep for a few hours.

A new study in fruit flies showed that all areas of the brain have much higher levels of molecules found at synapses. Normally, strengthening a synapse is a good thing. It is one of the steps thought to be important in memory formation. But brains can’t continue to build up existing connections forever, Cirelli says.

“We cannot afford to keep growing our synapses one day after another, because very soon they would become unsustainable,” she says. “Stronger synapses come at a very high price.”

It takes a lot of energy, cellular supplies and other resources to maintain the connections. And if a neuron puts all of its energy into continually strengthening old synapses, it will never form new ones, making it impossible to learn new things.

Cirelli’s group found that sleep breaks down the molecules that form synapses. In particular, slow-wave sleep was important for reducing the amount of the synapse-forming molecules in the brain. The group also showed in a new study of people that disrupting slow-wave sleep by playing a quiet sound while people were sleeping impaired performance on one type of learning task.

Disrupting slow-wave sleep may also disrupt REM sleep, says Gina Poe, a sleep researcher at the University of Michigan in Ann Arbor, so more research is needed to show that slow-wave sleep is the critical stage needed to clear the mind. But it is clear that sleep is critical for clearing out old memories to make way for new information, she says.

“Sleep is not only for building things, it’s for tearing them down,” says Poe.

Memories associating names and faces, for instance, are forged first in the hippocampus, a seahorse-shaped part of the brain. But the hippocampus is used only for short-term memories. Memories are stored in other parts of the brain and the hippocampus must be cleared to make new memories.

Poe and her colleagues found that REM sleep turns off the brain chemicals norepinephrine and serotonin, both used for stabilizing synapses. Injecting serotonin into the brains of rats during sleep disrupted the rats’ ability to form certain kinds of memories, suggesting that the ability to remove old connections during sleep is important for making new memories.

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Comments 2

* The researchers speculate that little sleep leads to an increase in the production of a hormone that stimulates appetite such as ghrelin, and at the same time decreases the production of a appetite-suppressing hormone such as leptin. They didn’t find a relationship between sleep and appetite, however. According to the researchers, this was because the group of women they used was too small. http://www.focusfinancialcorp.com
Melissa Len Melissa Len
Mar. 26, 2009 at 5:53pm
* Sleep And Memories, Blueprints And Organisms


A. "Sleep makes room for memories"

http://www.sciencenews.org/view/generic/id/38692/title/Sleep_makes_room_for_memories
Sleep erases old memories to make way for new learning...sleep changes the biochemistry of the brain...


B. Sleep neither erases nor inscribes memories

Sleep does not change the biochemistry of the brain. Memories are inscribed in the brain, and maintained or erased, in genetic biochemical processes.

Again and again. Genes are organisms, even as now interdependent members of their genome communal cooperative, they were born with the environmental habit and need to sleep.

The need to sleep is innate in genes, as evidenced by the Circadian Rhythm. It was daylight's energy that trans-phased the pre-alive RNA oligomers into individual living polymers, the primal genes, and it was daylight's energy that continued being the ONLY source of energy for the early genes, organisms, in the pre-biotic Earth surface. And this state of affairs persisted along the course of evolution of genes into communal cooperative genomes, with chromosomes enclosed in cells and later also in nuclei. It took many many following years for Earth to start evolving its biosphere and to furnish to its life alternative energy sources, as life evolved the capability to exploit the additional types of energy.

Organisms' "biological clock" is thus an inherited matter, an innate characteristic.


C. Sleep does effect the functionality of genes and of chromosomes

On pre-biotic Earth the functionality of the primal genes, and chromosomes, was decreased or impaired at daylight's energy switch-offs. This is life's innate phenomenon that carried into multicelled organisms.


D. Genes-genomes are NOT "DNA sequences, materials, genetic blueprints..."

It is necessary to overcome a reflective resistance to conceive certain polymers as living, as organisms. However, the plain simple fact of life is that genes are organisms, the primal organisms of Earth, the LIFE of Earth. All other organisms evolve and live temporarily to promote and maintain the genes, to promote and maintain the temporary store of energy by Earth's biosphere. Louis J. Sheehan, Esquire

The common sad observation is that the science establishment and its publications refer to, and comprehend, genes-genomes organisms in pre-Copernicus pre-Galileo term "genetic codes"... with stubborn insistence on seeing the naked emperor's new clothes, on seeing genes-genomes not as the organisms they obviously are but as "DNA sequences, genetic materials, genetic blueprints..."