Have you ever heard that social media sites have blue backgrounds because blue makes you feel calm?

Or have you read on some pop-psychology site that wearing red to a job interview will make you more confident? The Internet is full of sketchy facts and rumors about color psychology—the idea that certain colors can change our mood or influence our decisions.

But what does the science have to say? Like a lot of things in psychology, the answer isn't crystal clear. Colors might affect our perception, and maybe even our behavior, but not always in a predictable way.

And when it comes to why, the jury is still out. One of the most famous examples of color psychology gone wrong is Baker-Miller pink. In the late 1960s, a researcher named Alexander Schauss began investigating whether certain colors could actually cause your body to have a biological response.

After doing some experiments, including a few on himself, he began to believe that exposure to the color pink had a calming effect, causing the lowering of heart rate and blood pressure and even weakening muscle strength. Schauss worked to find a shade of pink that was most effective, and believed the color could do wonders in prisons. He convinced a Naval correctional facility—run by Gene Baker and Ron Miller— to paint a holding cell that color, which came to be known as Baker-Miller pink.

At this prison, incoming inmates were thought to be especially unruly. But after five months of using the pink holding cell, there had been zero violent or disruptive incidents. The officers were convinced that the pink paint worked, and were even more impressed because all it seemed to take was 15 minutes of exposure.

Schauss and others later tried to show that Baker-Miller pink had a physiological effect on people, and that the color could be a calming force in other prisons. But those studies don't really hold up when you look at how they were done. For one thing, the scientists didn't split up the prisoners randomly and put half in pink rooms and the other half in, say, white rooms.

Instead, they simply compared the amount of violence in the first year, when there were white walls, to the following year when things were painted pink. Carefully controlled experiments have failed to find that Baker-Miller pink is, as Schauss claimed, tranquilizing. But that doesn't mean that color doesn't matter at all!

Consider experiments done in 2012 in the Netherlands, with people using poker chips. When poker players were given red chips, they bet more and and were more competitive. When asked how they were feeling during the game, they reported feeling stronger.

Players using white or blue chips, on the other hand, tended to fold more. So color does seem capable of changing feelings and behavior. But that raises the question of … why?

Is that because red has some sort of biological effect on people when they're playing poker? Or is it that people learn to associate certain meanings with certain colors, because of their culture? Red might have an emboldening effect on a select group of Dutch people—as seemed to be the case in the poker study—but not on people in Japan or Kenya, for example.

And even then, the associations that we make with a color at a poker table won't necessarily apply to your wardrobe. You probably have your own, personal associations with red, too. So, something about color matters.

The challenge for psychologists today is to figure out how and why colors affect us, while avoiding the mistakes of their Baker-Miller pink past. That means improving research methods—including by being more careful about what we mean by “color.” When we talk about color, we usually think about hue, or the wavelength of a red, say, versus a blue. But there's also how bright it is, and how intense and vivid it is.

In the past, most researchers have varied all these elements at the same time, making it really hard to interpret results. So, even though we can't say that a certain color will make you happier or less violent, colors can influence our feelings and alter our behavior—we're just not sure exactly how or why. Thanks for watching this episode of SciShow Psych, especially to our patrons on Patreon.

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