July 25, 2013
Can’t Sleep? Blame It On The Moon
Lee Rannals for redOrbit.com - Your Universe Online
Tossing and turning throughout the night with no one to blame? Well, scientists writing in the journal Current Biology said maybe you should look up in the sky to see the culprit.
"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," said Christian Cajochen, of the Psychiatric Hospital at the University of Basel.
During the study, 33 volunteers in two age groups had their brain patterns monitored in the lab while they slept. The team not only looked at brain patterns, but also eye movements and hormone secretions. Data revealed that during a full moon, brain activity related to deep sleep dropped by 30 percent.
This study showed that both the subjective and objective perception of the quality of sleep changed with the lunar cycles. The scientists said that people took five minutes longer to fall asleep when the full moon was out, and also slept for twenty minutes less overall. Participants said they felt as though their sleep was poorer when the moon was full, while researchers witnessed diminished levels of melatonin in the volunteers, which is 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 said this circalunar rhythm could be a relic from a past in which the moon could have synchronized human behaviors for reproductive or other purposes. Today, animals still show signs of this behavior, particularly marine animals. Scientists say this instinct is masked by the influence of electrical lighting and other aspects of modern life.
The researchers said they would like to look more deeply into the anatomical location of the circalunar clock and its molecular and neuronal underpinnings. They say it could show how the moon has power over other aspects of our behavior as well, such as cognitive performance and our moods.