Why do travel tales put people to sleep?

“Deep within the eastern slopes of the snow-capped Andes mountains lies a mystical region largely untouched by mankind….”

Imagine a soothing voice softly narrating as listeners close their eyes and snuggle down in their beds.

“Tonight, we’ll explore a place that seems to exist outside of time, where tropical jungles and grassy highlands exist in perfect harmony.”

Are you paying attention? It doesn’t matter. The story’s goal is to put its listeners to bed.

According to the CDC, some 70 million Americans struggle with chronic sleep problems. Many adults are returning to a childhood favorite: the bedtime story. The snippets above are from a 45-minute story on the subscription app Calm.

Many of the more than 2,500 meditation apps on the market offer nighttime relaxation help. Dozens of podcasts, such as Sleep Cove, and online video channels, including Soothing Pod’s YouTube channel, exist simply to lull adults into a deep slumber.

These are not your kids’ bedtime stories: adult stories tend to be longer, more descriptive, meandering, and without the moral arc often found in children’s books. These stories are being told by celebrities such as Michael Buble and IdrisElba.

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One genre of bedtime stories that is particularly popular with adults is the travel story. Nearly a third of Calm’s 300 bedtime stories (which have been listened to more than 450 million times) are about travel, particularly adventure travel. Some 45 percent of the bedtime stories on the app Breethe (which has been downloaded more than 10 million times) are travel-related. Earlier this year, half of the top 10 bedtime stories were travel-themed. Why do travel stories put listeners to bed so often?

On the train to slumberland

Travel bedtime stories are typically an audio retelling of a trip, often in present tense, as if we are placed there alongside the narrator. It may be a day in the therapeutic waters of Bath, England. It could be a visit in the remote, mountainous Kingdoms of Bhutan. Or an image-filled imaginary journey to “see” the Northern Lights in Norway.

Listeners can join in on cruises down the River Nile, sailing trips to Sri Lanka, arduous pilgrimages like the Camino de Santiago, balloon rides over Cappadocia, Turkey, or road trips along Route 66. These tales are largely based on description with occasional ambient noises like train tracks or ocean waves.

Train stories are particularly intriguing at bedtime, it seems. Headspace, Calm, and Breethe have steadily increased their train-themed content. Listeners can journey the Orient Express or the Trans-Siberian Railroad. Headspace’s most popular story is “Slow Train”. This alters the ambient train sounds and changes the spoken description details. It is consistently ranked among the top five most loved bedtime stories on the app.

” A bedtime story needs movement. If things are too static, the listener will get bored. Martha Bayless, a professor and director of the University of Oregon Folklore and Public Culture Program specializing in oral tradition from ancient to modern times, says that it is important to have motion in it. “But the movement must be non-threatening, soothing. And for the modern day, what better than the movement of a train?”

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Trains engage the senses in a gentle way, with a constant forward momentum. Bayless states that train travel is a way to make decisions without having to make them. The train is the ideal vehicle for sleeping. You can just take it where it goes, enjoy the gentle swaying, the rhythmic sound, the sense that you’re cozied up in an old-fashioned, reassuring mode of travel.”

The same would not be true for audio tales about air travel, Bayless points out: “Imagine trying to sleep while squeezed into an airplane seat with a passenger reclining on you!” In other words: Stories that are too close to real life might backfire as bedtime tales.

How it works

Bedtime stories help some people get more restful sleep, according to Rachel Salas, a neurologist and the assistant medical director at Johns Hopkins Center for Sleep and Wellness. More restful sleep helps the body better regulate everything from digestion to cognitive performance, according to the American Academy of Sleep Medicine.

Bedtime stories work on one level because they’re a good distraction that keeps the mind from worrying, running through to-do lists, or stirring anxiety. Stories that are positive and upbeat can help calm a troubled mind.

One possible reason why our brains are soothed by travel bedtime stories are “mirror neurons,” says Salas. These neurons were first discovered in the macaque monkey. They fire when a subject performs a specific movement and when it is only observed.

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Salas says these brain cells might conflate our own experiences with someone else’s. A tale about train travel could cause a feeling of nostalgia for past journeys even though the story is not our own. Relaxation and sleep can be helped by the familiarity and romance of something familiar. Salas also notes that the sound of a train moving along the tracks can be used as a kind of white noise to help people fall asleep.

Some people find bedtime travel stories fascinating because they open up new adventures. This may seem exciting, but it can also provide a sense of security and reassurance about traveling safely around the world.

“From a neurological standpoint, it’s not just the idea of traveling and seeing new places, it’s about connecting. We are naturally social creatures. We’ve had to travel far from our family and friends, as well as from freedom. Salas says that even if you didn’t travel as much, you still had the option to try new restaurants or try something new.

Or, it could simply be that by removing light and noise from the outside world, an inner world, our imagination, can take over. Bayless says that nighttime storytelling is an ancient art form. “In a way, when we’re listening to sleep stories, we’re harkening back to the very dawn of human culture.”

“In the most soothing travel bedtime stories, nothing much happens,” says Bayless. “The bedtime stories are about the lull between adventures, which is what sleep is also about.”

Hillary Richard is a journalist who writes about travel and wellness. You can find her on Twitter.