Sleep paralysis is defined as "a period
of inability to perform voluntary movements either at sleep onset or upon
awakening" It has been given many other names, including Daymares
and cataplexy of awakening, and many cultures have "sleep
paralysis myths", such as the Old Hag in Newfoundland or "Kanashibari"
in Japan. Common features, apart from feeling paralysed, include buzzing
and humming noises, a sense of presence, feelings of pressure on the chest,
fear and, sometimes, floating or flying sensations.
This may sound quite different from the out-of-body
experience - in which a person feels as though they have left the body
and can see the world from a location outside it. However, OBEs and sleep
paralysis have much in common. For example, Sylvan Muldoon describes how
his first experience began when he was twelve years old, and he awoke
to find himself unable to move, a condition he later called astral
catalepsy. A floating sensation then took over and then a vibration
and pressure in his head, after which his sight cleared and he was able
to look down on his body.
Oliver Fox describes how he learned first dream
control and then astral projection to avoid the unpleasant experience
of becoming temporarily paralysed with everything going wrong
around him. He claimed that when in the paralysed state all you have to
do is try to move to find yourself "out".
Rogo describes a combined experience of OBE and
SP, and Muldoon and Carrringtons collection contains several such
cases. In surveys, Green found that 5% of OBErs reported paralysis at
some stage, and Poynton found 7%.
Several methods for inducing OBEs include the
suggestion to use paralysis. Fox suggests keeping the mind awake while
the body falls asleep, and Monroe emphasises a vibrational state
that sounds much like the vibrations and noises reported in SP. Given
these points of comparison between SP and OBEs we decided to investigate
the relationship further by comparing the features of two case collections.
The SP paralysis cases came from two sources;
first 201 letters received in response to advertisements; and second 184
letters originally sent to the X Factor magazine. We compiled a
database of the features of these experiences and reported the results
at the 1997 SPR conference. In the first set 128 respondents reported
SP. The two most common features, aside from paralysis itself, were a
malign presence (45%), and vibrations or buzzing and humming noises (41%).
Tactile sensations were reported by 20% and the experiences were often
unpleasant or frightening. Many people felt pressing, squashing or pulling
sensations, felt an invisible person sitting on the bed, or saw the bedclothes
being moved or pressed down. 21% of these cases included an OBE, such
as this one.
I was lying down on my sofa watching television. It
was late night and I felt myself dropping off to sleep. I also felt
myself going into the sleep paralysis state - which I dont like
... I felt myself sort of rolling off the sofa and then sort of floating
round the living room.
Among the X-Factor letters, there were
68 cases of sleep paralysis. The most common categories were again malign
presences (59%), and vibrations or noises (38%), and 12% included an OBE.
For the comparison, OBE cases were taken from
the collection of letters I have received since the publication of my
book Beyond the Body in 1982. Until now I have never analysed their
contents in any systematic way, but the SP study suggested the possibility
of applying the same categorisation system to these OBE accounts. The
letters included 104 first hand accounts of OBEs. These were independently
coded by two coders using the same system of categories they had used
for the SP cases.
Not surprisingly the most common feature in the
OBE cases was flying or floating sensations (71%), the next most frequently
reported features were ones common in sleep paralysis, that is voices
or laughter (25%), lights (24%), and benign or neutral presences (23%).
Paralysis was reported in 18% of cases, including one very frightening
experience with sensations of trembling and teeth grinding.
These results suggest that there is considerable
overlap between the two experiences of OBEs and SP. In our SP collections
21% and 12% respectively reported having an OBE as part of the experience,
and among the OBE case collection 19% included paralysis. In addition
such features as the sense of presence, strange noises and vibrations,
lights, and feelings of being pulled or touched occur in both. Oddly enough
vibrations, which are a well known concomitant of OBEs, were more often
reported among the SP cases. The most notable differences are that in
SP the presences are far more often malign while in OBEs they are more
often benign or neutral. In general sleep paralysis is a much more unpleasant
experience than an OBE - only very few OBErs reported being scared or
There are many limitations to this study, including
the use of unsolicited and highly variable accounts, and the limitations
of the coding method used. However, we have made a first step towards
finding out how similar the two experiences are.