Lunar effect
Encyclopedia
The lunar effect is the theory that there is correlation between specific stages of the Earth's lunar cycle and deviant behavior in human beings. In spite of numerous studies, no significant lunar effect on human behaviour has been established, and many researchers claim this persistent belief has no basis in fact.
The theory is sometimes also referred to as the Transylvanian hypothesis or the Transylvanian effect in scholarly literature.
itself is derived from the Latin
word Luna, meaning "moon". Perhaps the most famous myth arising from this theory is the legend of the werewolf
.
and mental well-being, during the time of a full moon, and that those with mental disorders generally exhibit periods of increased violent or aggressive episodes during the full moon. Conversely, other studies indicated that there was no such correlation.
Another study found a statistically significant correlation between the lunar effect and hospital admissions due to gastrointestinal bleeding
, particularly among males. However, there was very wide variation in the number of admissions throughout the lunar cycle, which the researchers acknowledged limited the interpretation of the results.
Sallie Baxendale and Jennifer Fisher of University College London
hypothesized that the impact of the moon phase on epileptic seizures may be due to the moon's contribution to nocturnal illumination. A significant negative correlation between the mean number of seizures and the fraction of the moon illuminated by the sun (ρ = -0.09, P < 0.05) was found in 1571 seizures recorded in a dedicated epilepsy inpatient unit over 341 days. This correlation disappeared when the local clarity of the night sky was controlled for, suggesting that it may be the brightness of the night and the contribution the moon phase makes to nocturnal luminance that influence the occurrence of epileptic seizures.
Psychologist Ivan Kelly of the University of Saskatchewan
(with James Rotton and Roger Culver) carried out a meta-analysis
of thirty-seven studies that examined relationships between the moon's four phases and human behavior in 1996. The meta-analysis revealed no significant correlation. They also checked twenty-three studies that had claimed to show correlation, and nearly half of these contained at least one statistical
error.
A study of 4,190 suicides in Sacramento County over a 58-year period showed no correlation to the phase of the moon. A 1992 paper by Martens, Kelly, and Saklofske reviewed twenty studies examining correlations between Moon phase and suicides. Most of the twenty studies found no correlation and the ones that did report positive results were inconsistent with each other.
Psychiatrist Arnold Lieber of the University of Miami
reported a correlation of homicides in Dade County
to moon phase, but later analysis of the data — including that by astronomer George Abell
— did not support Lieber's conclusions. Kelly, Rotton, and Culver point out that Lieber and Carolyn Sherin used inappropriate and misleading statistical procedures. When more appropriate tests were done, no correlation between homicides and the phase of the moon was found.
Astronomer Daniel Caton analyzed 70,000,000 birth records from the National Center for Health Statistics
, and found no correlation between an increased birth rate and the full moon phase. Kelly, Rotton, and Culver report that Caton examined 45,000,000 births and found a weak peak around the third quarter phase of the Moon, while the full moon
and new moon
phases had an average or slightly below average birth rate.
In 1959 Walter and Abraham Menaker reported that a study of over 510,000 births in New York City
showed a 1 percent increase in births in the two weeks following the full moon. In 1967 Walter Menaker studied another 500,000 births in New York City, and found a 1 percent increase in births in the two-week period centered on the full moon. In 1973 M. Osley, D. Summerville, and L. B. Borst studied another 500,000 births in New York City, and they reported a 1 percent increase in births before the full moon. In 1957 Rippmann analyzed 9,551 births in Danville, PA and found no correlation between the birth rate and the phase of the moon.
A fifteen month study in Jacksonville, Florida
revealed no lunar effect on crime and hospital room admittance. In particular:
due to the corresponding human menstrual cycle
, which averages 28 days. The cycle of lunar phases is 29.53 days long. However, only about 30 percent of women have a cycle length within two days of the average.
According to some traditions, prior to the advent of modern techniques, surgeons would supposedly refuse to operate on the full moon because of the increased risk of death of the patient through blood loss.
s, the notion behind the lunar effect has also found its way into the news. For example, it has been alleged that the full moon may have influenced voter behavior in the US 2000 presidential election.
Police in Toledo, Ohio
claimed that crime rises by five percent during nights with a full moon, while police in Kentucky have also blamed temporary rises in crime on the full moon.
Senior police officers in Brighton
announced in June 2007 that they were planning to deploy more officers over the summer to counter trouble they believe is linked to the lunar cycle.
In January 2008, New Zealand's Justice Minister Annette King suggested that a spate of stabbings in the country could have been caused by the lunar cycle. In October 2009, British politician David Tredinnick
asserted that during a full moon "[s]urgeons will not operate because blood clotting is not effective and the police have to put more people on the street.". A spokesman for the Royal College of Surgeons said they would "laugh their heads off" at the suggestion they could not operate at the full moon.
The theory is sometimes also referred to as the Transylvanian hypothesis or the Transylvanian effect in scholarly literature.
Origins
The exact origins of this theory are unknown, since it predates written history. The belief is known to have been around for many centuries, however. The term lunacyLunacy
Lunacy may refer to:* Lunacy, the condition suffered by a lunatic, now used only informally* Lunacy , a 2005 Jan Švankmajer's film* Lunacy , a video game for Sega Saturn* Luna Sea, a Japanese rock band originally named Lunacy...
itself is derived from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
word Luna, meaning "moon". Perhaps the most famous myth arising from this theory is the legend of the werewolf
Werewolf
A werewolf, also known as a lycanthrope , is a mythological or folkloric human with the ability to shapeshift into a wolf or an anthropomorphic wolf-like creature, either purposely or after being placed under a curse...
.
Scientific research on theory
Some studies seem to offer limited support for lunar effects. Several studies concluded that schizophrenic patients show signs of deterioration, in terms of quality of lifeQuality of life
The term quality of life is used to evaluate the general well-being of individuals and societies. The term is used in a wide range of contexts, including the fields of international development, healthcare, and politics. Quality of life should not be confused with the concept of standard of...
and mental well-being, during the time of a full moon, and that those with mental disorders generally exhibit periods of increased violent or aggressive episodes during the full moon. Conversely, other studies indicated that there was no such correlation.
Another study found a statistically significant correlation between the lunar effect and hospital admissions due to gastrointestinal bleeding
Gastrointestinal bleeding
Gastrointestinal bleeding or gastrointestinal hemorrhage describes every form of hemorrhage in the gastrointestinal tract, from the pharynx to the rectum. It has diverse causes, and a medical history, as well as physical examination, generally distinguishes between the main forms...
, particularly among males. However, there was very wide variation in the number of admissions throughout the lunar cycle, which the researchers acknowledged limited the interpretation of the results.
Sallie Baxendale and Jennifer Fisher of University College London
University College London
University College London is a public research university located in London, United Kingdom and the oldest and largest constituent college of the federal University of London...
hypothesized that the impact of the moon phase on epileptic seizures may be due to the moon's contribution to nocturnal illumination. A significant negative correlation between the mean number of seizures and the fraction of the moon illuminated by the sun (ρ = -0.09, P < 0.05) was found in 1571 seizures recorded in a dedicated epilepsy inpatient unit over 341 days. This correlation disappeared when the local clarity of the night sky was controlled for, suggesting that it may be the brightness of the night and the contribution the moon phase makes to nocturnal luminance that influence the occurrence of epileptic seizures.
Psychologist Ivan Kelly of the University of Saskatchewan
University of Saskatchewan
The University of Saskatchewan is a Canadian public research university, founded in 1907, and located on the east side of the South Saskatchewan River in Saskatoon, Saskatchewan, Canada. An "Act to establish and incorporate a University for the Province of Saskatchewan" was passed by the...
(with James Rotton and Roger Culver) carried out a meta-analysis
Meta-analysis
In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...
of thirty-seven studies that examined relationships between the moon's four phases and human behavior in 1996. The meta-analysis revealed no significant correlation. They also checked twenty-three studies that had claimed to show correlation, and nearly half of these contained at least one statistical
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
error.
A study of 4,190 suicides in Sacramento County over a 58-year period showed no correlation to the phase of the moon. A 1992 paper by Martens, Kelly, and Saklofske reviewed twenty studies examining correlations between Moon phase and suicides. Most of the twenty studies found no correlation and the ones that did report positive results were inconsistent with each other.
Psychiatrist Arnold Lieber of the University of Miami
University of Miami
The University of Miami is a private, non-sectarian university founded in 1925 with its main campus in Coral Gables, Florida, a medical campus in Miami city proper at Civic Center, and an oceanographic research facility on Virginia Key., the university currently enrolls 15,629 students in 12...
reported a correlation of homicides in Dade County
Miami-Dade County, Florida
Miami-Dade County is a county located in the southeastern part of the state of Florida. As of 2010 U.S. Census, the county had a population of 2,496,435, making it the most populous county in Florida and the eighth-most populous county in the United States...
to moon phase, but later analysis of the data — including that by astronomer George Abell
George Ogden Abell
George Ogden Abell was an astronomer at UCLA. He worked as a research astronomer, teacher, administrator, popularizer of science and education, and skeptic. Abell received his B.S. , M.S. and Ph.D. from the California Institute of Technology...
— did not support Lieber's conclusions. Kelly, Rotton, and Culver point out that Lieber and Carolyn Sherin used inappropriate and misleading statistical procedures. When more appropriate tests were done, no correlation between homicides and the phase of the moon was found.
Astronomer Daniel Caton analyzed 70,000,000 birth records from the National Center for Health Statistics
National Center for Health Statistics
National Center for Health Statistics is a division of the United States federal agency the Centers for Disease Control and Prevention . As such, NCHS is under the United States Department of Health and Human Services...
, and found no correlation between an increased birth rate and the full moon phase. Kelly, Rotton, and Culver report that Caton examined 45,000,000 births and found a weak peak around the third quarter phase of the Moon, while the full moon
Full moon
Full moon lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. More precisely, a full moon occurs when the geocentric apparent longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun.Lunar eclipses can only occur at...
and new moon
New moon
In astronomical terminology, the new moon is the lunar phase that occurs when the Moon, in its monthly orbital motion around Earth, lies between Earth and the Sun, and is therefore in conjunction with the Sun as seen from Earth...
phases had an average or slightly below average birth rate.
In 1959 Walter and Abraham Menaker reported that a study of over 510,000 births in New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
showed a 1 percent increase in births in the two weeks following the full moon. In 1967 Walter Menaker studied another 500,000 births in New York City, and found a 1 percent increase in births in the two-week period centered on the full moon. In 1973 M. Osley, D. Summerville, and L. B. Borst studied another 500,000 births in New York City, and they reported a 1 percent increase in births before the full moon. In 1957 Rippmann analyzed 9,551 births in Danville, PA and found no correlation between the birth rate and the phase of the moon.
A fifteen month study in Jacksonville, Florida
Jacksonville, Florida
Jacksonville is the largest city in the U.S. state of Florida in terms of both population and land area, and the largest city by area in the contiguous United States. It is the county seat of Duval County, with which the city government consolidated in 1968...
revealed no lunar effect on crime and hospital room admittance. In particular:
- There was no increase in crime on full moons, according to a statistical analysis by the Jacksonville Police Department. Five of the fifteen full moons had a higher than average rate of crime while ten full moons had a lower than average rate. The higher-than-average days were during warmer months.
- Statistical analysis of visits to Shands Hospital emergency room showed no full moon effect. Emergency room admissions may have more to do with the day of the week.
Religion and folklore
Across the world, there has been an abundance of pseudoscientific theories and superstitions based on this premise. One theory claims that the moon has a perceived relationship to fertilityFertility
Fertility is the natural capability of producing offsprings. As a measure, "fertility rate" is the number of children born per couple, person or population. Fertility differs from fecundity, which is defined as the potential for reproduction...
due to the corresponding human menstrual cycle
Menstrual cycle
The menstrual cycle is the scientific term for the physiological changes that can occur in fertile women for the purpose of sexual reproduction. This article focuses on the human menstrual cycle....
, which averages 28 days. The cycle of lunar phases is 29.53 days long. However, only about 30 percent of women have a cycle length within two days of the average.
According to some traditions, prior to the advent of modern techniques, surgeons would supposedly refuse to operate on the full moon because of the increased risk of death of the patient through blood loss.
In the news
As with most folklore and urban legendUrban legend
An urban legend, urban myth, urban tale, or contemporary legend, is a form of modern folklore consisting of stories that may or may not have been believed by their tellers to be true...
s, the notion behind the lunar effect has also found its way into the news. For example, it has been alleged that the full moon may have influenced voter behavior in the US 2000 presidential election.
Police in Toledo, Ohio
Toledo, Ohio
Toledo is the fourth most populous city in the U.S. state of Ohio and is the county seat of Lucas County. Toledo is in northwest Ohio, on the western end of Lake Erie, and borders the State of Michigan...
claimed that crime rises by five percent during nights with a full moon, while police in Kentucky have also blamed temporary rises in crime on the full moon.
Senior police officers in Brighton
Brighton
Brighton is the major part of the city of Brighton and Hove in East Sussex, England on the south coast of Great Britain...
announced in June 2007 that they were planning to deploy more officers over the summer to counter trouble they believe is linked to the lunar cycle.
In January 2008, New Zealand's Justice Minister Annette King suggested that a spate of stabbings in the country could have been caused by the lunar cycle. In October 2009, British politician David Tredinnick
David Tredinnick (politician)
David Arthur Stephen Tredinnick is a Conservative politician in the United Kingdom.He is a former officer in the Grenadier Guards and is Member of Parliament for Bosworth first elected in 1987....
asserted that during a full moon "[s]urgeons will not operate because blood clotting is not effective and the police have to put more people on the street.". A spokesman for the Royal College of Surgeons said they would "laugh their heads off" at the suggestion they could not operate at the full moon.