There’s a name for the color you see when you close your eyes (and it’s not black)

What color do you see when you close your eyes?

Here’s a hint: it’s not black.

What we are actually seeing is a unique color that has its own specific name: Eigengray.

The German word technically means “intrinsic gray,” but is now more commonly referred to as “brain gray.”

Although the history of the word is uncertain, it first appeared in the 19th century. Gustav Fechner, a pioneer in the field of experimental psychology, is usually credited with coining the term.

Fechner spent much of his career investigating the relationship between sensations and the stimuli that evoked them.

In Eigengrau’s case, he noticed that even in complete darkness – whether in a pitch-black room or with their eyes closed – people still saw a hint of gray.

Where does this new color come from?

From our own eyes.

Eyes are amazing organs and very complex, but when it comes to transmitting what we see outside to the brain, two types of cells are needed: rods and cones.

In their simplest form, cone cells see color, while rod cells focus on light and contrast – essentially black and white.

In low light, the brain relies more on rod cells than cone cells, which continue to capture as many photons (essentially particles of light, but like everything in physics, so much more) as possible.

And it seems that these rod cells don’t just switch off when we close our eyes. They continue to send signals to the brain, creating the illusion that you see the slightest hint of light – and therefore see gray instead of pitch black.

Or self-gray.

Of course, that’s not the only thing you can see with your eyes closed.

You may have noticed flashes, swirls, or spots of light after rubbing your eyes. These so-called phosphenes, like autologous gray, are caused by the eye sending signals to the brain and creating the illusion of light – in this case by putting pressure on the eyeball.

Speaking of sensations that aren’t really there, earlier this year scientists discovered that humans can “hear” silence, settling a seemingly age-old debate.

So now you know.