“One-Kind-Fits-All” Denial, All the Time

Anil Seth is a neuroscientist whose main research interest is consciousness – a vast topic beyond the intent of this writing. I once attended a conference lecture Anil gave on consciousness during which Anil described a phenomenon I found very striking and I have never forgotten.


To skip my verbal description of what Anil showed us, jump down to “Try it yourself!”, watch the brief video clip, and then resume reading.


In the demonstration, without saying a word, Anil presented a video of a flat checkerboard of dark gray and light gray squares. Toward the top right corner was a cylinder sitting upright. The cylinder cast a shadow toward the bottom left corner.

Anil then claimed that the shadow was not making the light gray squares in the shadow seem darker. He said our minds were deceiving us. He said the light gray squares inside the shadow were the same color as the darker gray squares outside of the shadow. He claimed the lighter color of the squares in the shadow was placed upon those squares by our expectations, and that the squares were the same color.

I was totally confused because the shadow was so obvious to see and the shadow clearly made the light gray squares it fell on look darker. Anil said the squares were not lighter, that our minds made them look lighter because the shadow was there, and he could prove it.

Anil’s claim seemed silly. When he asked the audience if we thought he was very wrong we all agreed he was very wrong.

Then he produced a second checkerboard and slid a gray color stripe overlaying the gray squares in the shadow across the second board, and onto the first. As he slid it into place on the first board, the gray squares inside the shadow on the first checkerboard became the same color as the darker squares outside the shadow, and the shadow vanished. If he slid that stripe out of the way again the shadow suddenly returned, and the squares inside the shadow again looked lighter.

It was truly puzzling.


Try it yourself!

You can hear a minute of explanation and watch the demonstration here.  If you have an extra minute, let it run and watch the next demonstration too.  The second one is important because it has to do with what we hear, instead of what we see.


Anil explained we have enough experience in our lives with such images that our brain makes us perceive what our brain expects is there, instead of showing us what is there.

For example, when you read the title of this blog post you might have read part of it as “One-Size-Fits-All” instead of what it actually says.

During the presentation I attended, he explained that the difference with this phenomenon involving the checkerboard is that no matter what you do with your eyes or mind, or what anyone says, you cannot see anything except the color difference that is not there.  You are stuck seeing it incorrectly. Anil went on to say that type of error in perception results in what is called an “impenetrable cognition” where the person just can’t be convinced otherwise.


How does this apply to our efforts?

When I heard Anil describe all of this, I immediately wondered if some instances of what some people call “denial” are this phenomenon of impenetrable cognition instead. And I wondered if there are experiences that could be helpful — instead of things that cannot work in these instances, like attempts at verbal convincing?

In other words, as Norm Hoffmann sorts diagnostically using the Big 5, so we could sort therapeutically by the presence or absence of impenetrable cognition. 

Perhaps one day cognitive neuroscience and our field will have unified research inquiries toward helpful clinical methods where we are currently stuck.