Why doesn’t anyone recognize Clark Kent as Superman?

It’s a bird, it’s a plane…. No, it’s the same person–he just put on a pair of glasses.

Many people try different hair styles, get a haircut and some even dye their hair in an attempt to change up their look. But what if changing your look was as simple as adding or removing glasses?

A recent study examined the idea and discovered by simply adding or subtracting frames, people were, in fact, less distinguishable. The idea for the study was, at least in part, born from the question many superhero fans have had over the years–how could people in Metropolis not know Clark Kent was Superman? But apparently, those glasses are a better disguise than we give him credit for.

As part of the research, participants were asked to look at two photos and determine if they were of the same or different people. The images were split up into three categories: one showed individuals wearing glasses, one showed people without glasses and the final category of images included one person with glasses and the other without. The participants were then asked if the person in the two photos was the same or a different person. They found that participants’ accuracy dropped when comparing a person with glasses to one without glasses.

“Facial recognition is often difficult for people, even if they have just viewed the photo,” says Dr. Arkadiy Konyukhov, a neurologist for Advocate Dreyer in Aurora, Ill. “Sketch artists for police departments have a tough job because they are going off of a witnesses account and relying on a glimpse or memory. We have a way of distorting the images we remember and although unintentional, it is very hard to describe things.”

But for this study, recall wasn’t tested; instead, participants were asked to compare images side by side to test their visual comparison skills. Interestingly, even in this case, accuracy was lower with the seemingly small addition of glasses.

“A slight alteration to someone’s face can make a big impact for comparison,” says Dr. Konyukhov. “A lot of weight loss or acne medications struggle to sell because people don’t believe the before and after photos are the same people because alterations to the face can throw off our recognition completely.”

Dr. Konyukhov believes there is still work to be done in order to understand the true dynamics at play. “It would be interesting to see the recognition abilities if a photo was replicated exactly. For example, the lighting, head angles, hair color and backgrounds are the same. I would think people might have an easier time determining matches this way opposed to looking at pictures that could have many differences.”

Nevertheless, next time you’re looking to “change up” your look, perhaps you should consider simply trying on a pair of frames.