Full Moon Sleep Problems: Scientific Evidence Found

Hard to Sleep with Full Moon

Many people complain about poor sleep around the full moon, and now a report appearing in Current Biology, a Cell Press publication, on July 25 offers some of the first convincing scientific evidence to suggest that this really is true.

A Full Moon is defined as the lunar phase that occurs when the Moon is completely illuminated as seen from the Earth. This occurs when the Moon is in opposition with the Sun (when it is on the opposite side of the Earth from the Sun; more precisely, when the ecliptic longitudes of the Sun and Moon differ by 180 degrees).

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The findings add to evidence that humans - despite the comforts of our civilized world - still respond to the geophysical rhythms of the moon, driven by a circalunar clock.

"The lunar cycle seems to influence human sleep, even when one does not 'see' the moon and is not aware of the actual moon phase," says Christian Cajochen of the Psychiatric Hospital of the University of Basel.

In the new study, the researchers studied 33 volunteers in two age groups in the lab while they slept. Their brain patterns were monitored while sleeping, along with eye movements and hormone secretions.

• The data show that around the full moon, brain activity related to deep sleep dropped by 30 percent.
• People also took five minutes longer to fall asleep, and they slept for twenty minutes less time overall.
• Study participants felt as though their sleep was poorer when the moon was full, and they showed diminished levels of melatonin, a hormone known to regulate sleep and wake cycles.

"This is the first reliable evidence that a lunar rhythm can modulate sleep structure in humans when measured under the highly controlled conditions of a circadian laboratory study protocol without time cues," the researchers say.

Cajochen adds that this circalunar rhythm might be a relic from a past in which the moon could have synchronized human behaviors for reproductive or other purposes, much as it does in other animals.

Different names for a full moon according to the month of the year it occurs.

Today, the moon's hold over us is usually masked by the influence of electrical lighting and other aspects of modern life.

The researchers say it would be interesting to look more deeply into the anatomical location of the circalunar clock and its molecular and neuronal underpinnings. And, they say, it could turn out that the moon has power over other aspects of our behavior as well, such as our cognitive performance and our moods.

Current Biology, Cajochen et al.: "Evidence that the lunar cycle influences human sleep."

Stop Blaming the Moon for Everything : Article looks at the absence of lunar influence on human affairs and lists some popular lunar myths. The full moon has been linked to crime, suicide, mental illness, disasters, accidents, birthrates, fertility, and werewolves, among other things. The study illustrates how intelligent and otherwise reasonable people develop strong beliefs that, to put it politely, are not aligned with reality.

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Attribution/Source(s): This quality-reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by Cell Press and published on 2013/07/27, this content may have been edited for style, clarity, or brevity.