I was riding in the car with my mom the other night when she mentioned that a full moon makes people crazy. She said that she could tell it was full just from how people were driving. I laughed it off, but decided to look into the claim.
Psychology Today says:
University of Sydney researchers found no link to the moon’s cycle in two separate studies, one of violent or aggressive behavior, the other of dog bites that required human hospitalization.
And in an analysis that ought to put to rest any lingering doubts, Ivan Kelly, a psychologist at the University of Saskatchewan, found in a review of over 100 studies of lunar cycles and behavior — including emergency room admissions and suicide attempts — nothing to suggest that humans are affected by Earth’s satellite.
So why do 81 percent of mental health professionals, according to a University of New Orleans study, believe that lunar cycles affect human behavior? Part of the reason is historical: The illuminated moon played a more prominent role for our ancestors as both a calendar and a night-light. Before electric lighting became ubiquitous, a bright moon was more likely to disrupt sleep, producing widespread grouchiness.
Kelly also cites what psychologists call confirmation bias, selective thinking whereby we seek out information that confirms our beliefs and ignore evidence that challenges them. Says Kelly, “Some beliefs are just exciting to hold, whatever the evidence.”
I don’t think I’ll tell her about the article and lack of science on her side. And you never know. Unhappy ancestors on little sleep may have started it all.
