Researchers ponder purpose behind sleep

It’s necessary to the normal behavior of every human
being. Inadequate amounts can produce devastating consequences. And
college students are constantly receiving the short end of the
stick. Need a hint? Yawn.

Sleep is the body’s required natural method of rest
““ everyone has experienced this first-hand. But researchers
who study this phenomenon have yet to determine its exact
purpose.

Despite ambiguities about its function, sleep researchers
encourage the development of good sleep habits or “sleep
hygiene.”

“The population that has the least sleep is in the age
group of teenagers and college students,” said Frisca Yan Go,
medical director of the UCLA Sleep Disorders Lab.

Yan Go suggests establishing pre-sleep rituals and going to
sleep at a consistent hour each night in order to prevent the
sometimes fatal consequences of sleep deprivation.

“The sleep bank is a very forgiving bank,” Yan Go
said.

“It doesn’t charge you interest, but you should be
sure to pay the bank so that you don’t go bankrupt (while
driving) on the 405.”

The recommended amount of sleep for someone in their early 20s
is about eight hours.

Sleep researchers are trying to identify the brain cells
involved in triggering ““ and preventing ““ sleep.

Although sleep is characterized by reduced observable body
movement, the brain and other organs remain active at the cellular
level.

The sleeping brain is most similar to the waking brain during
rapid eye movement sleep, a sleep state accompanied by unconscious
motor activation, such as palpitations of the eyelids.

Contrary to what one might think, the brain wave activity during
both REM sleep and a wakened state displays very low voltage. Wave
activity during non-REM sleep, however, displays very high
voltage.

Brain activity is monitored in sleep studies that use metal
electrodes placed on the scalp to detect and record the electrical
activity of neurons.

Jerry Siegel, a professor in the UCLA Department of Psychiatry
and chief of neurobiology research at the Center for Sleep
Research, likens this to an idling car.

While a car is moving (awake), its engine may hum quietly and
unnoticed. But when it stops (sleeps) at a stop sign, the
“putt-putt” of the engine becomes louder (non-REM
sleep) as the car remains immobile.

“When consumption is minimal and the least is going on in
the brain, that’s when it appears to be the most active even
though you’re not taking in any external information at
all,” Siegel said.

According to Siegel, adjacent neurons fire their electrical
messages in sync during non-REM sleep, resulting in high voltage
waves.

In REM sleep and while awake, on the other hand, neurons fire
messages at different times according to various stimuli. REM
sleep, then, is when the most vivid dreams occur.

“If you sleep longer than usual, you’ll have more
vivid dreams,” Siegel said. “You generally only
remember your dreams if you wake up in REM sleep.”

On a typical night, humans alternate between REM and non-REM
sleep in cycles that last about 90 minutes. An average adult spends
about 20 percent of total sleep time in REM sleep.

It was previously thought that a correlation existed between REM
sleep and learning and intellectual capability in higher organisms.
Little evidence has been found to support this hypothesis.

Siegel found that the duck-billed platypus, the most primitive
of mammals, has a very large amount of REM sleep, while dolphins
may be the only animal that don’t have any REM sleep at
all.

“This indicates that REM sleep is not recently evolved
““ it was present in the earlier mammals,” Siegel said.
“If anything, REM sleep is a more primitive case than non-REM
sleep.”

Dolphins and other marine mammals have been found to sleep with
only half of their brain at a time.

“If we can explain how these very intelligent, big-brained
animals can go without REM sleep, then we’d have a major
insight into what REM sleep is for,” Siegel said.

An explanation for REM sleep could lead to a better
understanding of many human disorders which involve REM sleep
control abnormalities.

According to the National Center on Sleep Disorders Research, 70
million Americans suffer from sleep problems.

Sleep apnea, a common sleep disorder occurring in 5 percent of
adults, causes people to periodically stop breathing while asleep.
This hiatus in breathing can last from seconds to a few minutes and
is caused by excessive relaxation and collapse of the muscles in
the airway.

Sleep apnea can lead to hypertension and stroke, or ultimately
death. Researchers recently discovered many sleep apnea patients
also have a stutter, suggesting the disorder is linked to an area
in the brain that controls speech.

Narcolepsy is a sleep disorder which affects nearly 300,000
people in the U.S. and cannot be cured once it is developed.

One of the symptoms of narcolepsy is cataplexy, a sudden loss of
muscle control triggered by stress, laughter or strong emotion.

When a patient goes into a narcoleptic fit, they often retain
consciousness but are unable to speak or move.

At the UCLA Center for Sleep Research resides one of two
existing colonies of narcoleptic dobermans which exhibit all the
qualities of a human suffering from narcolepsy.

“If they get excited they’ll fall down,”
Siegel said. “They have fragmented sleep and a large number
of sleep episodes a day that are irregular.”

A sleep disorder which may hit closer to home is insomnia
““ the inability to fall or stay asleep.

Insomnia can be caused by a variety of factors including
depression, stress, and drug or alcohol use.

The Ashe Center holds free workshops titled “The Art of
Sleeping,” which teaches students how to become more
efficient and effective sleepers. The workshop meets on Tuesdays
during spring quarter from 1:00 to 1:55 p.m. in the Ashe
Center.