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The Mysterious Moon Illusion

The predecessors of humans, the early mammals, developed an acute ability to see predators from many angles, which gave them an edge in the survival competition known as natural selection. However, that same survival skill can render us susceptible to wrong or falsely interpreted information—what scientists call visual illusions.

Shamans and magicians have used these illusions for years to create “magical” effects since the dawn of time, but we still don’t really understand how most of them work. Let’s take a look at one famous illusion: the Moon Illusion.

The moon illusion

For most people, the moon looks larger when it is near the horizon than it does when it is higher in our sky. However, the actual size of the image on the retina is always the same. So the fact that it looks “bigger” under certain circumstances is an illusion—and one that has been hard for science to fully explain.

For centuries, psychologists theorized that the illusion was a result of processing the distance cue of the horizon with the image. The explanation went something like this: when the moon is higher in our sky, we don’t have anything to compare it to, and thus it appears smaller. This particular effect is called empty field myopia.

However, when neuroscientists showed various moon images to subjects undergoing Magnetic Resonance Imaging (MRI), they found that the images reported to be “larger” actually stimulated a larger section of the brain’s visual cortex. In very simple terms, this revelation demonstrates that the brain isn’t misinterpreting data by calculating relative distance, it is actually perceiving the moon as larger—even though the images are the same on the retina.

So, we could make the case that the moon illusion is not an illusion at all. The brain reports to our consciousness exactly what it “sees” when the moon is closer to the horizon. However, for some reason, the brain is making an error in processing the information.

This news still doesn’t tell us why this is happening, but at least we have a clearer picture of how the brain processes this particular type of image to arrive at a false conclusion.

The moon illusion is certainly intriguing, but what does it have to do with human capital management? Well, it gives me an opportunity to debunk a truism I’ve heard many times in my career—and it drives me a little crazy.

Perception is reality—or is it?

Early in my career, I was promoted into my first management position. The popular mantra at the time was “perception is reality.” I must have heard it five or six times a day (usually when someone was giving me “feedback” about how poorly I was doing in my new role).

I had a hard time getting my head around this statement because on the surface, “perception is reality” is clearly false. Most of us would say that there is a reality that can be measured and described by science (for example, the size of the image the moon consistently makes on the retina) and then there is human perception, which can be deceived and confounded by any number of factors (the position of the moon in the sky).

When I asked for an explanation, my peers and senior managers seemed to interpret this truism something like this: “Whatever anyone thinks about you feels true to them because that is how they perceive you. Therefore, you are being held accountable for other people’s perception of you.”

For an inexperienced and admittedly unskilled manager, this belief provided terrible advice. I spent way too much effort trying to change these “negative” perceptions of me when I should have been learning how to lead—accepting the fact that I might not be universally liked in the process.

Only years later was I able to see that one contributing factor to all that negative “perception” about me was probably the fact that I had been promoted to manage my former peers. I understand now why some of members of my team might have perceived me as arrogant and bossy, since they were looking through a lens that said they should have been promoted instead of me.

Of course, I probably did make a lot of mistakes. But telling me I had to accept all negative opinion about me as fact was certainly not helping.

What it really means

The phrase “perception is reality” appears to have originated with Lee Atwater, the political mastermind who orchestrated the first election of George W. Bush. He is credited with creating the negative campaign ad and the concept of “spin” in public relations. While these are significant accomplishments of a certain type in a particular field, I challenge any manager to make the case that spin and negative positioning truly have a place in managing and developing human beings.

The full quote, which is seldom used, is “Reality is irrelevant. Perception is reality.” While it is true that people believe their perceptions to be reality, I like to think that we are all capable and willing to change our minds when presented with facts and evidence. Neuroplasticity teaches us that our brains are constantly remaking themselves, so there is hope for even the most ingrained prejudices to be removed in the face of new information.

If the moon illusion teaches us anything, it is that even our amazing brains can be mistaken at times. As leaders have a responsibility to acknowledge both perceptions and evidence in making decisions about the people in our organization.

As the car mirror says, “Things may be closer than they appear.”

Margie Meacham


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