There can't be many people who have not seen the film
"Moby Dick", either in its original 1956 version with
Gregory Peck, or the more recent 1998 television adaptation
with Patrick Stewart. I'm sure too that many people will
have read the book itself, written by Herman Melville way
back in 1851. What you probably won't remember however is
one particular passage from the book in which the narrator,
Ishmael, says:
"For what seemed ages piled on ages, I lay there, frozen
with the most awful fears, not daring to drag away my hand;
yet ever thinking that if I could but stir in one single
inch, the horrid spell would be broken. I knew not how this
consciousness at last glided away from me; but waking in the
morning, I shudderingly remembered it all, and for days and
weeks and months afterwards I lost myself in confounding
attempts to explain the mystery."
Although sleep paralysis would not be described by the
American neurologist Weir Mitchell for another 25 years,
this gives us a vivid account of a condition that has been
around since the dawn of time.
Sleep paralysis is one of a number of unwanted events that
occur during sleep (including sleep walking, nightmares,
night terrors and restless legs syndrome) and about half of
us will experience at least one episode of sleep paralysis
during our lifetime. For many narcolepsy sufferers,
however, sleep paralysis can be a common occurrence and, if
accompanied by hallucinations (another frequent symptom of
narcolepsy), it can be a particularly frightening, or even
terrifying, experience.
Sleep paralysis very rarely presents any real danger to the
sufferer. Nevertheless, it is an experience that most of us
could live without and one for which we would dearly love to
have a cure. Unfortunately, however, there is no cure at
present, but, there is light at the end of the tunnel.
For some time now it has been known that human leukocyte
antigen, or HLA, (a protein found on the surface of white
blood cells and forming part of the body's natural defense
or immune system) has played a part in causing narcolepsy.
What has not been understood though is just what role this
protein has played. In two separate studies carried out in
Texas and California in 2000 however the true role of HLA
emerged and this is now being confirmed in a series of
further studies, the most recent of which (June 2005) comes
from the University of California, Los Angeles (UCLA).
It appears that narcolepsy is caused by the lack of a
particular chemical called hypocretin or orexin that is
normally produced by the brain and plays a key role in
maintaining a normal sleep pattern. In the case of
narcolepsy sufferers this chemical is missing because of the
presence of an autoimmune disease. In other words, the
body's immune system, instead of attacking foreign invaders,
attacks healthy cells (in this case hypocretin or orexin
molecules) and destroys them.
So what does all this mean for narcolepsy sufferers?
Well, it certainly doesn't mean that a cure will appear
tomorrow, but it does mean that scientists now know how to
cure the condition. On the one hand they can look at
methods of preventing the body's immune system from
attacking hypocretin or orexin molecules and, on the other
hand, they can develop a method of replacing the lost
molecules.
This will of course require further research and clinical
trials and will take some years. In the meantime, sufferers
will need to stick with their current recognized drug
treatments and continue to pursue a policy of sound sleep
hygiene and behavioral management. But the knowledge that
scientists have now pinpointed the cause of narcolepsy and
that a cure is at last in the pipeline should act as very
good encouragement for anybody living with narcolepsy today.
