Parasomnias Often Under-Recognized, Misunderstood
Research points way to new treatments for sleepwalking, sleep sex, and other parasomnias.
The Sleepwalking Cure continued...
Guilleminault says that all of the children with
sleep-disordered breathing who underwent a tonsillectomy or adenoidectomy,
procedures to remove enlarged tonsils and adenoids and help improve airflow,
were cured of sleepwalking and night terrors. Meanwhile, the six children whose
sleep-time breathing problems were left untreated continued to suffer from
Guilleminault isn't suggesting that surgery
be done to prevent these sleep disturbances in all children. "Most
children have an occasional sleepwalking episode or night terror," he says.
The children in the study represent a "very small
group" that suffers persistent problems -- once or several times a week, on
a regular basis.
Though Guilleminault has recently completed a similar study in
adults, he is reluctant to share the results, pending acceptance and
publication in a scientific journal. But, he hints, in the future, "we will
be able to treat the underlying cause of sleepwalking."
Mark W. Mahowald, MD, director of the Minnesota Regional Sleep
Disorders Center at Hennepin County Medical Center and professor of neurology
at the University of Minnesota in Minneapolis, agrees that parents shouldn't
worry if their kids occasionally sleepwalk or suffer night terrors. Even in
adults, about 5% to 10% of whom sleepwalk and 1% of whom have sleep terrors,
the condition is generally harmless, he says.
Acting Out Dreams
Mahowald says that sleepwalking and night terrors result from
an abnormal and abrupt arousal out of a deep stage of sleep known as slow wave
sleep. The normal transition from deep sleep to a lighter sleep stage having
been bypassed, "the brain is not fully conscious; it's almost as if it's
half awake and half asleep," he says. "You can perform a complex
behavior such as driving a car, but you're not aware enough to know what you
Mahowald and Schenck have been studying a parasomnia that
strikes during a different stage of sleep -- REM (rapid eye movement) sleep,
when most dreaming occurs. What they found, Mahowald says, is a fascinating
link to neurological illnesses such as Parkinson's disease.
Normally during REM sleep, the muscles are completely
paralyzed, "so if you dream you are killing your mother-in-law, you're not
actually going to do it," Guilleminault says. But people with the
parasomnia dubbed REM sleep behavior disorder have an abnormality that causes
the normal paralysis of REM sleep to fail.
The result: Victims act out their dreams -- thrashing,
swearing, punching, kicking, running out of bed, even pummeling their bed
partners, Mahowald says.
Of the dozens of otherwise healthy people with REM sleep
behavior disorder that Mahowald and Schenk have followed since the 1980s,
two-thirds have gone on to develop Parkinson's disease or other related
neurodegenerative disorders, Mahowald says. Most are men, over 50 years old,
with the average time between the development of the sleep problem and the
neurological disorder being 13 years.