Humans have been collecting records of dreams for years. But what do these archives of our nightly visions tell us about the human mind? And can modern technology help to unravel them?

Another day at the height of World War Two had come to a close. Lars (not his real name), a 36-year-old man from the native American Hopi tribe was getting ready for bed. People in his community were far from the destruction in Europe, but they had been listening to war news every night on the radio. When Lars fell asleep that night, his dream would bring those reports to life.

He lay in his bed dreaming of some European city – a city that, though he had never been there, seemed like Paris to him. As he walked around he saw that the place had been badly bombed. It was a vision of Paris, but as the dream went on, he realised, spookily, that it appeared to be located in a valley near to where he lived. Eventually, the dream evaporated, Lars woke up and, sometime later, the war ended.

Lars is long gone, but we know what he dreamt about that night. In fact, we can peer into hundreds of dreams from around the world – thanks to an archive that recorded many nightly visions experienced by the Hopi and other tribes. Today, new collections of dreams are being created – indeed there are several apps for smartphones that do this. But what can archives like these actually tell us about the meaning of dreams? And who decided to start collecting them in the first place?

Our interest in dreams is probably as old as our ability to form words. But the first major effort to collect records of such things and make them easily accessible took place during and after World War Two. The largely forgotten archive was the brainchild of American psychologist Bert Kaplan and his legacy has recently been documented in a book called Database of Dreams: The Lost Quest to Catalog Humanity by Harvard researcher, Rebecca Lemov.

For years, anthropologists contributed to the project by interviewing people from various tribal cultures around the world. Records from these interviews would be kept in the archives, deposited at various locations, in the form of microcards. These were cards onto which miniaturised text was printed – with more than a hundred pages squeezing onto a single card in some cases.

Magnifying readers made the cards legible, but the technology was quickly superseded. Today, we call on the vast storage capabilities of digital databases instead. Data no longer needs to be shrunk – just uploaded.

For eight years, Lemov travelled from library to library consulting bits of the Database of Dreams. Sometimes the records had been untouched for decades and, in one case, librarians had thrown them “in the dump”. But when Lemov did get access to the records she was looking for, she uncovered dreams from all kinds of people.

Black clouds

One account describes the hallucinations of a Lebanese woman, suffering from typhoid, who imagined a beautiful plum that her father took from her in exchange for Turkish gold pounds. These were later seized without permission to pay a doctor. “When I woke up and couldn’t find my gold pounds I began to scream,” the woman told the researchers who interviewed her.

There were also the South Pacific islanders who dreamt about one of their own – a man who had “gone crazy” after the arrival of the US Navy in the region and a native American who dreamt of “flying into black clouds” where she was confronted by a relative.

As we all know, sometimes we have dreams which seem to make “sense” to us – we have a fair idea of why we dreamt them in the first place. But quite often they have puzzling details – or are altogether weird.

“Dreams don’t travel perfectly, they are elusive,” comments Lemov, “and I don’t think technology will easily do away with that.”

And yet there are some who think technology can help to unravel the meaning of dreams. Apps like Dreamboard and Shadow offer users the ability to record descriptions of their dreams. In turn, the app makers attempt to look for patterns and signals in order to benefit our general understanding of what dreams are and what we might learn from them.

However, as Hunter Lee Soik, who founded Shadow, points out, that’s not easy. Shadow, which is not yet publicly available, has around 10,000 beta members. Some patterns have already been observed in their dreams but Soik is keen to emphasise that they can’t be conclusive about those findings.

“In our very small sample set we’ve seen an increase in sexual and violent dreams around full moons and this is consistent over every full moon since we’ve launched the app,” he says.

“This is what we’ve seen in our small, small database so in no way am I making a claim that that’s actually happening.”

But perhaps any correlation at this point is interesting – and one can understand why some would be curious enough to probe it further.

Soik’s app harvests keywords from users’ own descriptions of their dreams so that patterns across countries, and even the world, can be identified. How many people dreamt about Godzilla in Japan last night? Shadow might be able to give you a rough idea, he suggests.

“A lot of people have frightening dreams and these are the dreams they remember,” he adds. “On the other hand, some people have very lucid dreams where they’re flying and doing all sorts of interesting stuff.

“Women have more characters in their dreams and kind of a more vivid dream life – it’s very interesting.”

Deciphering dreams

The insights Soik and his team are gathering beg the question: could we become more skilful at deciphering dreams?

It’s an idea posited by neuropsychologist Patrick McNamara at Boston University School of Medicine, who is an adviser to Dreamboard.

McNamara is interested in the benefits of finding patterns in dreams – such as what figures and objects have particular associations – and using this to build a “dream code”.

“If we can build up enough of those dream code elements, we might have a handle on whether or not dreams mean anything,” he says

The creation of more and more databases that collect information about dreams is promising, he adds. Indeed, it bodes well that such a breakthrough – or at least the beginnings of it – could be made in the near future. But McNamara also wants to be clear that no such code exists today – and he has been vocal about dismissing those who claim to be able to interpret dreams.

“I’m not saying that dreams don’t mean anything, I’m saying we don’t know yet,” he explains. “That the science does not support any particular dream interpretation method.”

Part of the problem with analysing dreams is that, currently, researchers must rely on the descriptions given to them by subjects – which may not always be accurate or complete. Indeed, it’s not hard to understand that some people might feel less able to talk candidly about their most intimate or disturbing dreams.

Perhaps we won’t always need to wait for dreamers to divulge their hallucinations, though. A team of Japanese researchers from the University of Tokyo recently described how a machine learning algorithm could be trained to associate certain patterns of brain activity with specific images.

The system, detailed in the journal Science, could correctly “guess” what people were dreaming about just by monitoring their brains overnight.

Still, dreams, being of the ever-mysterious brain, remain some of the strangest and most poorly explained phenomena about us. And yet billions of people have them every night. The idea that they could be decoded never fails to seem exciting – perhaps because dreams are often thought of as windows to our deepest feelings and desires.

For Soik at least, people’s increasing willingness to share intimate data about themselves generally bodes well for the field of dream science.

“We hope that we can provide enough trust to the users that they’re OK revealing more and more,” he comments. “Anything we hold back is something we keep to ourselves. The more transparent we are the more we can put our dreams out there and say, that’s because of this; and that’s because of that.”

And even though such breakthroughs were never made during Bert Kaplan’s lifetime, Lemov points out that many contributors to the original Database of Dreams always saw it as something that future generations might be able to make better sense of.

“Some of the people who were behind this project in the 50s very much saw it not so much as the message, but the medium,” she explains. “Material that could be amassed so patterns could be discovered in that.”

Perhaps, one day. Until then, we can only dream.

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