Dreams can often seem bizarre—and there’s still a lot that experts don’t understand about why certain similar topics seem to regularly haunt people in their sleep all around the world.

Research shows that some dreams are actually very widespread and universal. An infographic created by Dream Moods—an online platform that helps people determine the meaning behind their dreams— and search traffic tracker Ahrefs, tracked the most common dreams that people subsequently investigate on Google.

One of the most common themes was tooth loss, a topic Googled frequently by people living in countries across North America and Europe. Claudia Picard-Deland, a lecturer in psychology research and science communication on dreams, sleep and memory at the Université de Montréal, told Newsweek that it was interesting to note how this dream search mostly occurs in northern, industrialized countries.

“Dreaming of losing teeth might be related to increased anxiety or to dental irritation (teeth grinding) during sleep,” Picard-Deland said. “Could it also be related to colder weather? (very speculative!). Although to my knowledge, no study has shown clear nationality or ethnic differences in bruxism.”

Girl sleeping
A file photo of a girl sleeping. There seem to be similarities in in the types of dreams people are curious about.

A 2018 study published in the National Library of Medicine found that 39 percent of people have dreamed about their teeth either falling out, breaking or rotting at one point in their lives.

There has also been research indicating that this dream occurs when people go through important life changes. However, the exact reason for having such dreams remains unclear, and is likely different for each individual.

Snakes also appear to be a very common dream symbol that puzzle people in other parts of the world. However, according to Dream Moods data, only in countries where snakes are actually prevalent such as Asia and parts of Oceania.

“On the topic of snakes, with a quick glimpse, it seems to me that it tends to be more frequent in regions of the world where snakes are cohabiting with humans, and where snakes may be considered a danger?” Picard-Deland said. “This would fit with the Threat Simulation Theory by Revonsuo, whereas dream would have evolved as a mechanism to simulate and prepare for potential threats (such as snakes) and challenges in order to enhance survival. But of course, snakes may be used as a metaphor for many different things, and there might be different cultural symbolism or beliefs related to snakes that explains those nationality differences.”

There are other theories surrounding what a dream about a snake could mean. A snake could represent a person who displays toxic or problematic behavior. This is according to professional dream analyst and author Lauri Quinn Loewenberg, as previously reported by The Cut.

“The message being, people all over the world, and in different time periods, seem to dream about similar topics,” Picard-Deland said. “There are slight variations of course, but it is quite impressive how much we tend to reuse the same types of scenarios or dream imagery, perhaps reflecting how we have shared concerns, fears, and aspirations as humans. One laboratory study from Yu (2016) even found that 80% of dreams from REM sleep contain at least one typical theme, sometimes with several typical themes within a single dream.”

Picard-Deland said that although data may show us the dreams people Google frequently, that doesn’t necessarily mean they are the ones that occur the most frequently.

“[It shows] what people are most curious/worried about. Different studies across the world used the Typical Dream Questionnaire, which asks if people had ever dreamed of a list of 55 different dream themes.”

A 2003 study published in the American Psychological Association found that in Canada, most prevalence dreams also involved themes of being chased, falling, sexual experiences, or being at school. This proved to be the same in America, with the addition of the theme of trying to do something multiple times.

“The same 5 most prevalent themes were found, but in a slightly different order, in a German population,” Picard-Deland said. “A Chinese study also found similar themes.

An older version of the questionnaire in 1958 was used to compare an American and Japanese population (Griffith, 1958), and the same themes showed up.”

In Japan, again, similar themes were found, with the addition of snakes.

“So not only are these themes prevalent, but they are overall fairly frequent. This high prevalence of typical themes suggests that the formation of dream scenarios may be governed by relatively stable and universal mechanisms. But research on typical dreams is still relatively rare, and several of these themes remain to be described in different age groups and nationalities.”

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