If you’re the kind of person  who remembers your dreams, there’s a pretty good chance that  what you remember is in color,   playing out like a movie scene.

That’s how most people dream. Or at least, that’s how most people dream now.

But for several decades of the 20th century, when  people’s dreams played out like a movie scene, those scenes looked like the  movies of the day: Black and white. As far as we can tell, an entire  generation stopped dreaming in color. And we’re still trying to understand why. [♪ INTRO] There aren’t a lot of formal studies of the  content of dreams before the early 1900s, but we do have anecdotal reports from Aristotle,   Descartes, and Sigmund Freud  referring to colors in dreams.

But one of the earliest studies of dreams happened   in 1915 and reported that only  20% of dreams contained color. A study of college students in 1942 found that 29%  of participants reported occasional color dreams, and a study in the 1950s showed  only 9% of people dreamed in color. Dreaming in color was so rare that  doctors and psychotherapists opined   on what was wrong with people who did  see a full color palette in their sleep.

They suggested drug use, migraines, anxiety,  and even stress and shock from seeing your   dad’s genitals at some point, which is very  on brand for mid-century psychoanalysts. Let us all take a moment to  heap judgment upon Freud. But then, like Dorothy landing in Oz,   things shifted and the dream  world started to be more colorful.

A study from 1962 reported more  than 80% of dreams contained color,   and since then the percentage of dreams  with color has remained firmly around 70%. So did everyone start doing drugs  and getting migraines in the ‘60s? Well, maybe, but there are a few other  ideas about what’s going on here.

The first is that the methods used  to measure the phenomenon of color   in dreams have changed in ways that might  be less biased against reporting color. It’s really hard to measure what happens  in dreams, because, well, we’re dreaming. And as most of us can probably attest,   it can be difficult or impossible to  remember your dreams in the morning.

So researchers have to get a little creative. Six of the nine studies done before 1960  used questionnaires that asked people to   describe their dreams for the last week or month. And there are all sorts of things  that can happen in that time.

You might misremember or forget things. Or your recollection might  be colored, so to speak,   by the standard way folks consumed visual  media at the time: In black and white. In contrast, a lot of the studies done after 1960   exploited the discovery that  we dream during REM sleep.

So instead of asking people to  describe their dreams from weeks ago,   the researchers would wake  participants up during REM   sleep and ask them to report on what they  were dreaming about right then and there. Other studies relied on dream diaries,   where people would record their  dreams immediately upon waking. The idea with either of these methods is that they   were less likely to be distorted  by memory or cultural experiences.

And yet, historically, writings on dreams from  before the 1900s didn’t rely on people reporting   their dreams immediately upon waking,  and they still reported color dreams. And a study in 2008 actually directly compared  questionnaires and dream diaries and didn’t find   any significant differences in the number  of color or greyscale dreams reported. So it might not be a question of methodology  after all, but if not that, then what?

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And you’ll get your first 30 days for free. The other hypothesis for black and white dreams   in the 20th century is that our dreams  reflect the media we were raised with. By 1915, photography had been common for decades,  and cameras came to the mass market in 1901,   so most people were familiar  with black and white images.

And by the studies of the 40s, black and  white movies were a common weekend escape. But color TVs rolled out between 1954 and 1972, coinciding with the shift to color  dreams recorded in the 1960s. To test this idea, researchers have  compared the reported color scales   of dreams between people of different generations.

One study in 2008 looked at participants born  before 1953 and participants born after 1983. It found that the older participants did indeed   report a higher frequency  of black and white dreams. And of the older group, those who had experience  with black and white media as kids reported more   black and white dreams than those who  weren’t exposed to this type of media.

A study done in Germany in  2017 found a similar pattern,   and a study done in China found  that eleven was the magical age, with people exposed to media in color  before 11 more likely to have color dreams. While all of these studies did show  generational differences in the color of dreams, the number of people reporting  grayscale dreams is still not   nearly as high as what was reported  in the studies from the 40s and 50s. That might be because people have gotten  exposure to more colored media since then.

This type of generational study is  difficult though, because in general,   older people report or remember  fewer dreams than younger people do. And it doesn’t necessarily capture whether  people are experiencing dreams differently, or just remembering their dreams  differently once they’re awake. But despite what I thought as a kid, the world  was not in black and white prior to the 1960s.

So although media was in grayscale, the vast, vast  majority of people’s lives were spent in color. So why would our media experience override  our real world experience in dreams? Our dreams don’t necessarily reflect  the way we experience the world.

I, for one, have never experienced a pirate   skeleton crawl out of the ground in my  grandmother’s front yard in real life. And the same may be true for visual experiences. One paper reported three cases of people with  color blindness who had dreams in full color.

So even though their realities weren’t  in full color, their dreams were. But that’s definitely not true  for everyone who’s colorblind,   so clearly there are no hard and fast rules. What’s more, our media consumption does have  a big impact on what happens in dreamland.

One study found that watching something  violent in the 90 minutes before bed   makes it 13 times more likely that  you’re going to have violent dreams. And it’s not just immediately before bed  like your parents may have warned you about. People who tend to watch more violent  media tend to have more violent dreams.

Even if you’re not experiencing anything  violent in your day-to-day life. So there’s something about media that  makes it wriggle its way into our dreams. Maybe there’s something about the experience of  watching things that makes them more impactful.

Sitting in front of a screen and having  something directed straight into your eyes   is more intimate than experiencing  something in the broader world. Or there may be something especially  powerful about the stories themselves. Either way, media influences our  dreams in frequency, content, and form.

And if the color of media is so  powerful, what about other aspects? Kids are consuming way more 3D virtual reality  content now than they have in the past. So who knows.

Maybe in a few years, our  dreams will change again. And in the meantime, I’m just going to be  grateful that smell-o-vision never took off. [♪ OUTRO]