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9. BIOLOGICAL RHYTHMS, THE NASAL CYCLE & DREAMS [X: NL 3(1); U: NL 3(3)]
In studying the relationship of lucid dreaming to the daily cycle of
waking and sleeping, it is essential to consider the biological rhythms
involved. In addition to the well-known 24 hour circadian cycle there
are shorter cycles, called ultradian. One of these appears in the form
of shifting dilation of the nostrils. If you hold one nostril closed and
breathe through the other, and then switch nostrils, generally you will
find that one nostril is easier to breathe through than the other. The
change from left to right seems to follow an approximately 90 minute
cycle.
Some research has suggested that the nasal cycle may be connected to
cycles of activity in the brain and also to cognitive abilities.
Furthermore, a shift in nostril dilation can be produced by pressure on
a reflex point on the side along line beneath the armpit. Possibly,
then, one could effect a change in cognitive activity by deliberately
pressing on this point.
In the oldest available references on lucid dream induction, the
thousand year old text on Dream Yoga in the Tibetan Buddhist tradition,
is the advice to the initiate attempting to achieve a lucid dream that
he should sleep "on the right side, as the lion doth." It is possible
that the purpose of this posture is to encourage the type of brain
activity conducive to lucid dreaming. After all, most of our current
knowledge about reflex points on the body is found in ancient yogic
texts.
This experiment examined the effect of sleeping posture on chances of
lucid dreaming and attempted to assess if nostril laterality bore any
relation to posture and lucid dreaming. The results were complex and
difficult to interpret, showing that this type of study is probably best
done in a laboratory under well controlled conditions. The procedure
asked people to note when they awakened in the night, whether they had
been dreaming, or lucid dreaming, which nostril was most open and to
rate their dreams on several scales. The finding to take home from this
study is that indeed, people had three times as many lucid dreams when
sleeping on their right sides (as the lion doth?) than when sleeping on
their left sides. Back sleeping presents a more complicated picture,
also seeming to be better than sleeping on the left, but here we must
examine other factors, such as which nostril is open. Further conclusion
is deferred until a laboratory study is accomplished.
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