The 35-year-old man, who was sitting in the psychiatric hospital of David Avery, was an engineer: "He liked to solve problems," recalls Avery. And the problem that puzzled him when he was admitted to the Seattle psychiatric ward where Avery worked in 2005 was his moods, which swayed violently from one extreme to the other – sometimes with suicidal fantasies or seeing and hearing things were not there. The man's sleep pattern was similarly irregular, ranging from almost complete insomnia to 12 hours a night.
As a problem solver, the man had kept meticulous records of these patterns and tried to understand everything. Avery studied these notes closely and scratched his head: "It was the rhythm that fascinated me," he says. For him, it seemed that the patient's mood and sleeping patterns were tracking the waxing and waning of the moon.
Avery initially dismissed his guess as madness. Even if the man's mood cycles were in sync with the moon, he had neither a mechanism to explain it nor ideas of what he could do about it. The patient was prescribed medication and light therapy to stabilize his mood and sleep, and he was eventually released. Avery slipped the man's notes into the proverbial file drawer and locked them.
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Twelve years later, a renowned psychiatrist named Thomas Wehr published a paper describing 1
"What I noticed about these cycles was that they were incredibly precise in a way that you would not necessarily expect from a biological process," says Wehr, emeritus professor of psychiatry at the National Institute of Mental Health in Bethesda, USA , "It asked me if there was any kind of outside influence that affected those cycles – and [because of the historical belief that the Moon affects human behaviour] the obvious question of whether there was any impact on the moon."
For centuries, people believe that the moon affects human behavior. The word madness derives from the Latin lunaticus, which means "moon-beaten," and both the Greek philosopher Aristotle and the Roman naturalist Pliny the Elder believed that madness and epilepsy were caused by the moon. It is also rumored that pregnant women are more likely to give birth to the full moon, but all the scientific evidence that has been provided by reviewing birth records in different phases of the moon is inconsistent. This is also evidence that the lunar cycle is exacerbating violence among psychiatric patients or prison inmates – although a recent study indicated that criminal outdoor activities – incidents on roads or in natural environments such as beaches – may be higher in stronger moonlight. 19659002] However, there is evidence that sleep varies over the lunar cycle. For example, a 2013 study conducted under the tightly controlled conditions of a sleep laboratory found that people took an average of five minutes to fall asleep and slept 20 minutes less around a full moon than in the rest of the year – though they did were not exposed to moonlight. The measurement of brain activity showed that deep sleep had fallen by 30%. Nevertheless, a follow-up study could not reproduce the results.
A recent study suggested that outdoor criminal activity might be higher in stronger moonlight conditions.
A key issue, says Vladyslav Vyazovskiy, a sleep researcher at Oxford University, is that none of the studies has monitored individual patient sleep for a full lunar month or for many months. "The only way to systematically address this would be to capture the same individual over time and across different phases," he adds.
That's exactly what Wehr did in his study of bipolar patients – in some cases. Tracking the data of their mood episodes for years. "Since humans differ in how they respond to these lunar cycles, I'm not sure if they would find anything, even if they were going to average all of the data I've collected," Wehr says. "The only way to find something is to look at each person individually over time and then hide the patterns."
When Wehr did so, he found that his patients fell into one of two categories: Some people showed mood swings To follow a 14.8-day cycle, others follow a 13.7-day cycle – though some of them have occasionally switched between these cycles.
The moon affects the earth in different ways. The first and most obvious is the provision of moonlight, with a full moon every 29.5 days and a new moon at 14.8 days. Then there's the moon's appeal, which creates ocean tides that rise and fall every 12.4 hours. The height of these tides also follows approximately two-week cycles – the 14.8-day "spring-neap cycle" powered by the combined pull of moon and sun, and the 13.7-day "declination cycle" powered by becomes The position of the moon relative to the earth equator.
It is these approximately two-week high-tide cycle cycles that seem to synchronize Wehr's patients. It's not that they necessarily switch to depression or mania every 13.7 or 14.8 days during a particular phase of the moon's tidal cycle, "says Avery.
After reading about Wehr's research, Avery picked up the phone and then analyzed the engineer's data, his mood fluctuating.
Further evidence of the influence of the Moon on the mood of these patients is the discovery that these otherwise regular rhythms appear to be interrupted every 206 days by another lunar cycle – the one responsible for creating "supermoons". when the moon is elliptical (The orbit brings it close to the earth.)
The light of a full moon could theoretically disturb people's sleep, which could affect their mood.
Anne Wirz-Justice, a chronobiologist at the Psychiatric Clinic of the University of Basel, Switzerland, describes this relationship between lunar and manic-depressive cycles as "credible," but "complex."
"One has no idea which mechanisms exist," she adds.
Theoretically Das Light from a full moon could disturb people's sleep, which could affect their mood, especially for bipolar patients Mood episodes are often triggered by sleep disturbances or circadian rhythms – 24-hour fluctuations in our biology and our behavior that can be disturbed by shift work or long-haul flights. There is even evidence that sleep deprivation can be used to lift bipolar patients out of depression.
Wehr has supported the idea that the moon somehow affects the sleep of patients. while their sleep time stays the same, which means that the time they sleep becomes longer and longer until it shortens abruptly. This so-called "phase jump" is often related to the onset of mania.
Nevertheless, Wehr considers moonlight an unlikely candidate.
"In the modern world there is so much light pollution and we spend so much time indoors that are exposed to artificial light that the signal for changing moonlight levels was obscured," he explains. Rather, he suspects that another aspect of the influence of the moon disturbs his patients' sleep, which adversely affects their mood – the most likely candidate is the attraction of the moon.
One idea is that this subtle fluctuation triggers the Earth's magnetic field, to which some people might react sensitively.
"The oceans are electrically conductive because they are made of salt water and because they flow around with the tides to which a magnetic field is associated," he tells Robert Wickes, a space weather expert at University College London. However, the effect is small and it is unclear whether the effect of the Moon on the Earth's magnetic field is strong enough to trigger biological changes.
Some studies have linked solar activity with an increase in heart attacks and strokes, epileptic seizures, schizophrenia and schizophrenia suicides. When solar flares or coronal mass ejections hit the earth's magnetic field, it induces invisible electric currents strong enough to turn off power grids, some of which have been suggested to affect even electrically sensitive cells in the heart and brain.
When People Are Exposed Magnetic field changes – similar to those observed when moving in our local environment – led to a decrease in alpha wave activity in the brain.
is very limited, so it's very hard to say anything specific, "Wickes explains.
On the one hand, it is not believed that humans, unlike certain birds, fish and insects, have a magnetic sense. However, a study published earlier this year called this assumption into question. It turned out that people exposed to magnetic field changes – similar to those observed in our local environment – experienced a sharp decrease in alpha wave activity in the brain. Alpha waves are generated when we are awake but do not perform a specific task. The significance of these changes remains unclear – it can be an irrelevant by-product of evolution, or magnetic changes in our environment can subtly alter our brain chemistry, as we do not know.
Magnetic Theory Addresss Weir In the last decade, several studies have suggested that in certain organisms, such as fruit flies, a protein called cryptochrome may also function as a magnetic sensor. Cryptochrome is a key component of molecular clocks that control 24-hour rhythms (circadian rhythms) in our cells and tissues, including the brain.
When cryptochrome binds to a light-absorbing molecule called flavin, it does not just say the circadian When it's daytime, it triggers a reaction that makes the molecular complex magnetically sensitive. Bambos Kyriacou, a behavioral geneticist at the University of Leicester, UK, and colleagues have shown that exposure to low frequency electromagnetic fields can reset the timing of circadian clocks of fruit flies, leading to changes in the timing of their sleep.  If this were true for humans, this could explain the sudden mood changes seen in Wehr and Avery bipolar patients. "These patients have quite dramatic temporal shifts in their circadian rhythms as they go through their mood cycles, and they also have quite dramatic changes in the time and duration of their sleep," says Wehr.
Another possibility is that patients respond to the magnet's attraction in the same way as the oceans: by tidal forces
Although cryptochrome is also an integral part of the human day clock, it works slightly differently than fruit flies. "It seems that human and other mammalian cryptochrome no longer bind flavin, and without flavin we do not know how to trigger magnetically sensitive chemistry," says Alex Jones, a physicist at the National Physical Laboratory in Teddington, UK. "So I find it unlikely that [human] cryptochromes are sensitive to magnetic fields unless there are some other molecules inside the human that can detect magnetic fields." the attraction of the moon in the same way as the oceans: by tidal forces. On the other hand, a general argument is that while humans are 75% water, they have much lower levels than an ocean. "Humans are made of water, but the power of attraction is so weak that it's difficult to see how it would work from a physical perspective," says Kyriacou.
Nevertheless, he nods to studies in . Arabadopsis thaliana (a weed that has been considered a model organism by biologists studying flowering plants) suggests that their rooting follows a 24.8-hour cycle – the time it takes the moon to complete orbit to reach. "These are incredibly small changes that can only be detected with extremely sensitive devices. There are now over 200 publications that support this, "says Joachim Fisahn, biophysicist at the Max Planck Institute for Plant Physiology in Potsdam.
] Fisahn has modeled the dynamics of piles of water molecules in individual plant cells and found that daily fluctuations in gravity caused by the orbit of the moon are sufficient to cause a net loss or gain of water molecules from the cell.
"The volume of water molecules – even if they are at the nanoscale – responds to any minute change in gravity," he says. "As a result, water molecules move through water channels, which means that water moves from inside the cell outward or vice versa, depending on the direction of the gravitational force – and this could affect the whole organism.
He now plans to test this in the context of rooting by studying plants with mutated water channels to see if they have altered growth cycles.
If plant cells are really sensitive to such tidal forces, then Fisahn sees no reason why human cells might not be so good. Given that life in the oceans has begun, some land organisms can retain the machinery to predict the tides, even if they no longer have any practical use.
Although the mechanism eludes us at the moment, none of the scientists contacted for this article dispute Wehr's basic finding: his bipolar mood swings are rhythmic, and these rhythms seem to correlate with certain gravitational cycles of the moon.
Weir is open to the mechanism and hopes that others will see it as an invitation to further investigation. "I did not answer how this effect is conveyed, but I think the things I found raise these questions."
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