Today's News, Tomorrow's Lesson - September 4, 2013

Darren Evans

Sleeping can help boost the brain's ability to repair itself,
according to new research.

Scientists have found that sleep increases the production of special
cells that produce myelin, an insulation material that protects the
brain and spinal cord.

The findings hint at how sleep, or lack of it, might repair or
damage the brain. It is also hoped they will offer insights into the
link between sleep patterns and the symptoms of multiple sclerosis
(MS), a disease that damages myelin.

The biological need for sleep has long fascinated scientists, and a
team from the University of Wisconsin-Madison has been carrying out
research on mice to find out what genes are turned on and off during
periods of sleep and wakefulness. Their findings have just been
published in The Journal of Neuroscience.

Chiara Cirelli and her colleagues discovered that the production
rate of the myelin-making cells doubled as the mice slept. The increase
was most marked during REM (rapid eye movement) sleep, the type of
sleep associated with dreaming.

In contrast, the genes linked to cell death and stress responses
turned on when the animals were forced to stay awake.

Dr. Cirelli said, “For a long time, sleep researchers focused on how
the activity of nerve cells differs when animals are awake versus when
they are asleep.

“Now it is clear that the way other supporting cells in the nervous
system operate also changes significantly depending on whether the
animal is asleep or awake.”

Future studies could look at how sleep affects the symptoms of MS,
and whether lack of sleep, especially during adolescence, may have
long-term consequences for the brain.

Deep sleep has also been found to coincide with the release of
growth hormone in children and young adults.

A number of schools have experimented with different start times to
take young people's naturally occurring sleep patterns into
consideration. These include Minneapolis Public Schools, which
experimented with later start times for teenagers and found many
positive benefits for their students.