Misconceptions: The Effect of the Full Moon

In Fall 2022, students in Dr. Emily Stark’s Social Psychology course completed a research project where they identified a misconception related to psychology, conducted both background research and an empirical project measuring belief in that misconception, and summarized their findings in a short blog post paper or by creating an infographic. The goal was to build student research skills as well as showcase the importance of thinking critically about information encountered in the media or in popular culture. This post is one of the papers submitted for that course. For more information on this project, just use the contact page to contact Dr. Stark.


By Jillian Cuchna, Kylie Hensch, and Allison Asfeld

a picture of the full moon

The Misconception

There are many misconceptions in the world of psychology, with one of those being that the full moon affects human behavior. According to an ancient theory, put out by Aristotle and Pliny the Elder, the brain might be affected by the moon in the same manner as the Earth's waters since the brain is wet. Also, many people believe in this misconception due to confirmation bias. We pay attention to events that support our beliefs so we are more likely to take note of something strange happening when there is a full moon rather than when nothing of significance is going on (Styx, 2021). 40% of medical professionals believe in this myth. Full moons are said to bring about some quite unexpected happenings in hospitals, with many nurses and midwives reporting a sharp spike in hospital admissions and deliveries during a full-moon shift. Greater levels of critical care and mental health difficulties, higher suicide attempt rates, changes in dementia patients, and crowded emergency rooms are also reported. Teachers also believe this misconception. Many teachers believe when children are acting crazy during school, that it is a side effect of a full moon (Your World Recruitment Group, 2019).

Myth Debunked

a road sign says 'reality check ahead'

For many years, people have believed that the moon’s phases affect many different aspects of life including sleep, criminal behavior, and even psychiatric hospital admissions. Studies conducted on a multitude of these areas have concluded that these beliefs are nothing but rumors. A study was conducted using data from an administrative database maintained by Hotel Dieu Hospital and Kingston General Hospital in Kingston, Ontario. This data was used to analyze the admissions of individuals having “mental health and psychosocial” conditions into the hospitals. The research team of this study then searched for a correlation in admissions and the moon's phase, particularly looking for admission spikes during a full moon. Their conclusion… no correlation (Parmar, Talikowska-Szymczak, Downs, Szymczak, Meiklejohn,, & Groll, 2014).

Another study was conducted focusing on the effects of the lunar phases on criminal activity. This study consisted of analyzing 911 calls over a 5 year period. Specifically calls where an officer was dispatched to a scene involving assaultive violence, burglary, theft, drugs/vice, traffic, other disturbances, and aggregated CFS. These calls were then compared with the recorded lunar phase at midnight of the night of the crime. After extensive review, this research team found no correlation between lunar phases and criminal rates (Schafer, Varano, Jarvis, & Cancino, 2010).

On a different note, research has been conducted on the sleeping habits of children during the different lunar phases. Children ages 9-11 were observed during at least 7 different nights of sleep. The main observations were the duration of sleep the children were getting. These children were selected based on a diverse amount of criteria to ensure that children of all types were being assessed to allow for the most accurate results. After comparing the duration of sleep during a full moon or a new moon, researchers found only a 1% difference between the two. This means that children only lost 4.9 minutes of sleep during the nights of a full moon. Through this data it was concluded that the moon’s phases have no significant effect on the duration a child sleeps (Chaput et al., 2016).

Real World Beliefs

A survey was conducted by an Introduction to Social Psychology class at the Minnesota State University, Mankato. The class compiled a survey of questions regarding a variety of misconceptions in psychology. It was then sent out to the general public to grasp an understanding of how many individuals believe in these common misconceptions. The results are as follows…

A full moon negatively affects a person's behavior

  • 36.76% people disagreed

  • 29.41% people neither agreed or disagreed

  • 33.82% people agreed

  • Total answers- 204

When there is a full moon crime rates are higher, animals behave strangely, and many people experience mood swings

  • 22.55% people disagreed

  • 20.10% people neither agreed or disagreed

  • 57.35% people agreed

  • Total answers- 204

Psychiatric admissions and suicide rates are higher during a full moon

  • 21.08% people disagreed

  • 43.63% people neither agreed or disagreed

  • 35.29% people agreed

  • Total answers- 204

Law enforcement and hospitals should use the full moon cycle to predict when they will be busiest.

  • 48.47% people disagreed

  • 34.69% people neither agreed or disagreed

  • 16.84% people agreed

  • Total answers- 196

The moon can affect the water in the human body, similarly to how the moon affects the tides, which can cause mood/behavioral changes.

  • 32.82% people disagreed

  • 34.87% people neither agreed or disagreed

  • 32.31% people agreed

  • Total answers- 195

The summary of this survey shows that, on average, about one third of people believe in common misconceptions associated with the moon’s phases and human behavior. In the case where people were asked about the moon's effects on criminal rates, strange animal behavior, and mood swings, more than half of the participants involved in the survey answered that they agree with the statement.

Conclusion

The misconception of the moon and its effect on human behaviors has been believed by many and has led to multiple ideas. Ideas that have included the full moon’s influence on criminal behavior, sleep, and psychiatric hospital admissions. Extensive research has been done on this misconception, and there is no significant evidence that the full moon affects human behavior.


References

Chaput, J.-P., Weippert, M., LeBlanc, A. G., et al. (2016). Are Children Like Werewolves? Full Moon and Its Association with Sleep and Activity Behaviors in an International Sample of Children. Frontiers in Pediatrics, 4, 24–24. https://doi.org/10.3389/fped.2016.00024

Parmar, V. S., Talikowska-Szymczak, E., Downs, E., Szymczak, P., Meiklejohn, E., & Groll, D. (2014). Effects of full-moon definition on psychiatric emergency department presentations. ISRN Emergency Medicine, 2014, 1–6. https://doi.org/10.1155/2014/398791

Schafer, J. A., Varano, S. P., Jarvis, J. P., & Cancino, J. M. (2010). Bad Moon on the Rise? Lunar Cycles and Incidents of Crime. Justice Studies Faculty Publications, 1-10. https://docs.rwu.edu/cgi/viewcontent.cgi?article=1025&context=sjs_fp

Styx, L. (2021, October 29). Does a full moon actually affect our behavior? Verywell Mind. Retrieved November 15, 2022, from https://www.verywellmind.com/does-the-moon-actually-affect-our-moods-5206203

Your World Recruitment Group . (2019, March 5). Fact or fiction: Does a full moon affect hospitals? Your World Healthcare. Retrieved November 15, 2022, from https://www.yourworldhealthcare.com/uk/news/fact-or-fiction-does-a-full-moon-affect-hospitals

Pedagogy, ThinkingKarla Lassonde