What Do We Actually Know About Color Psychology?

Issue 002: What Do We Actually Know About Color Psychology?

Quick housekeeping before we get into it: thank you for the warm response to Issue 001. A few of you replied directly, which made my week. I loved it!

This week: color. Specifically, a single shade of pink that ended up in prisons, football locker rooms, a Kardashian living room, and probably at least one design review you've been in. And what happened when researchers actually tried to replicate the science behind it. I considered saving this one for a later issue because it’s one of my all-time favorite silly-science-stories… but it’s just too good to keep in the vault.

And if someone forwarded this to you, they have great taste - you can subscribe for yourself here.

Warmest welcome,
Dr. Kati Peditto

In 1979, a researcher named Alexander Schauss published a paper claiming he had found a color that could literally suppress human aggression.

His experiment was simple (too simple? I’ll let you decide). 153 healthy young men stared at either a large piece of pink construction paper or a large piece of blue construction paper. The men who stared at the pink reported losing up to 26% of their grip strength compared to those who stared at the blue. Schauss concluded that this particular shade of pink (a shade made using one part red trim paint mixed into eight parts white latex paint) had a tranquilizing effect on the body. He said, famously: "Even if a person tries to be angry or aggressive in the presence of pink, he can't. The heart muscles can't race fast enough. It's a tranquilizing color that saps your energy."

That is an extraordinary, wild claim. It was also, apparently, convincing enough to get the Pentagon involved. I wish I was kidding.

Schauss persuaded two Navy officers (Gene Baker and Ron Miller) to paint a holding cell at the Naval Correctional Center in Seattle this exact shade of pink. On March 1, 1979, the experiment began. The Navy's own report stated that after the change, there had been "no incidents of erratic or hostile behavior during the initial phase of confinement." The color was named Baker-Miller Pink in their honor. Baker-Miller Pink even has its own Wikipedia page now.

Within a few years, jails and detention facilities across the U.S. were ACTUALLY painting their walls pink! The University of Iowa's football coach (who coincidentally also held a master's degree in psychology) had the visiting team's locker room at Kinnick Stadium painted Baker-Miller Pink. When the stadium was renovated in 2005, they doubled down: pink lockers, pink urinals, pink showers. It is still pink today.

(Colorado State did the same in the ‘80s until their conference passed a rule requiring both locker rooms to be the same color!)

And then Baker-Miller Pink started seeping into psychiatric facilities. Waiting rooms. Residences. In 2017, Kendall Jenner posted an Instagram photo of her Christmas tree set against a Baker-Miller Pink wall, and the caption described the color as "the only color scientifically proven to calm you AND suppress your appetite." That post reached tens of millions of people. I might have rage-quit Instagram at that exact moment.

Because Baker-Miller Pink had one big problem. Remember our Ulrich problem from last week’s issue? Repeat after me: REPLICABILITY.

When researchers tried to apply Baker-Miller Pink at the Santa Clara County Jail in California, the incident rate didn't drop. It went up. It PEAKED (!) compared to the months before the pink walls. When Schauss himself went back and repeated his own experiments, he found no difference in inmate behavior. He reportedly became concerned the color might actually make people more aggressive. Oops?

The initial calming effect, it turned out, seemed to last about 15 minutes. After that, all bets were off. Agitation increased. Heart rates increased. Grip strength returned with a vengeance. Whatever happened in those first minutes of exposure didn't persist. When Baker-Miller Pink was applied to the entire interior space and people spent hours there, it wasn't anything like the controlled conditions of the original study with the cardboard stimuli.

So in 2014, a team at Ghent University tried again with a bit more rigor this time. Fifty-nine incarcerated men who had violated prison policies were randomly assigned to pink or gray rooms, and correctional officers rated their aggression on arrival and after three days. BOTH groups showed reduced aggression over three days. But there was no difference between the pink room and the gray one.

So what actually happened in 1979?

This is why a 2014 review paper by psychologists Andrew Elliot and Markus Maier is required reading for anyone who specs, designs, or sells products for the built environment. I send this paper to people all the time. It’s my “holy grail” color psychology paper.

Elliot and Maier spent years studying color psychology and developed color-in-context theory. This theory suggests color effects are real, but they are highly context-dependent and frequently disappear or reverse when conditions change (like going from a piece of cardboard to an entire room). The same color can have opposite meanings depending on what someone is doing, how long they're exposed, what else is in the environment, and what associations they bring with them.

So when we take the color-in-context theory and apply it to Baker-Miller Pink, we can notice a few things:

First, on applying color to interior walls: the few studies examining color painted on actual walls have mostly found no effect, or found that people habituate (get used) to it quickly. A color that produces a measurable response when someone stares at a piece of cardboard is not necessarily producing any response when it's on the wall of a room they've been in for three hours.

Second, on methodology: most color research (including Schauss's original study) failed to control for the multiple dimensions along which color varies. Hue (the actual color), lightness (brightness), and chroma (saturation) all vary simultaneously, which makes it nearly impossible to know which property, if any, produced a result. You could have the “same” Baker-Miller Pink but it could be a slightly different lightness, chroma, or hue, and those properties also interact with lighting. Elliot and Maier are direct about this, suggesting most pre-2000 color research is essentially uninterpretable because of it.

Third, on real-world generalizability: Elliot and Maier caution explicitly that "the degree to which color effects are observed when individuals encounter a welter of colors on diverse stimuli in the bustle of everyday life remains a largely open question." A single color on a single piece of cardboard, stared at by a college student in a lab, is a very different stimulus than a painted wall in a complex environment with people, furniture, lighting, and competing visual information.

And just like with my analysis of Ulrich’s View Through a Window, I’m not saying the effect isn’t real or that the study is complete bogus. Schauss's original observations were probably real. Something weird clearly happened in those first minutes of exposure to the pink cardboard.

But just like the Ulrich study, we have a similar cautionary tale: how the design industry used Schauss’ results. We took some results from a cardboard study with college kids and then applied it to entire rooms without checking the validity or replicability of a single, small study. And now we have pink locker rooms.

This pattern (small results -> big applications) is one of the most persistent problems that I’ve seen in evidence-based design. And color is where I’ve seen it show up most often.

AKA: I downloaded these papers and vetted them, so you don’t have to.

Baker-Miller Pink is STILLLLLL on the walls of the Kinnick Stadium visiting locker room. It's probably in a healthcare facility near you. And it was applied based on a study of men staring at cardboard in 1979.

Next time someone in a project meeting talks about the causal effect of color (blue is calming! red is energizing!), it's worth asking: How was that actually measured? In what context? For how long? Under what conditions?

You don't have to be a total skeptic to be a better designer. You just have to ask thoughtful questions.

To work with me on an upcoming project or speaking engagement, reply to this email or visit katipeditto.com.

Until next week,

Dr. Kati Peditto