Posts Tagged ‘Slow-wave sleep’

Transylvanian Hypothesis lives again — Now lunar cycles found to affect sleep

July 26, 2013

Moon sickness is becoming all the rage. Hot on the heels of the report that cardiac surgery results are affected by the phases of the moon comes this study showing that lunar cycles do – in fact – also affect sleep. Our bodies it seems also dance to a lunar rythm and maybe it is time to revive the Transylvanian Hypothesis and revisit all the myths and legends about the effects of the moon (werewolves, induced lunacy, epileptic fits and even lunar effects on general practice consultancy rates!)

A new paper in Current Biology

Christian Cajochen, Songül Altanay-Ekici, Mirjam Münch, Sylvia Frey, Vera Knoblauch, Anna Wirz-Justice. Evidence that the Lunar Cycle Influences Human Sleep. Current Biology, 2013; DOI: 10.1016/j.cub.2013.06.029

from planetsforkids

EurekAlert: 

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. 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. 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.