I have been able to create the Mona Lisa effect in real people standing before me, and so can you. But first we must understand how this most famous painting in the world creates her mysterious effect. It is an optical illusion, of course, but it has been around for over five hundred years, and commented upon many times. People say that the Louvre Mona Lisa’s eyes follow them as they move around, but I have discovered that isn’t exactly what’s happening, because if you look carefully she isn’t looking directly at us.

She is looking at our right ear, or a little to the right of it. If one is up close she is looking at our right ear, but the further back we get the further to our right she is looking. A complicating feature is that her head is pointed over our left shoulder, but her eyes are turned enough to our right that her line of vision is sweeping across our face. The soft lighting is from our left and so it creates a shadow in the left side of each of her eyes, and because of those shadows it becomes ambiguous to know exactly where she is looking.

Mona Lisa in Paris, France

Detail of the Louvre Museum’s painting of Mona Lisa. Click for bigger.

To get the most vivid optical illusion of her eyes coming to life, hold your finger in the gap in the mountains to the right side and wait for about five seconds, until it is clear that she is looking at your finger. Slowly shift your vision from one of her eyes to the other a couple of times, as that convinces your mind that she is truly looking at your finger.

Now, move your finger to the center of her face and notice that she is still looking at your finger. Look steadily at one eye for five seconds and then at the other for five seconds, she is clearly looking into your eyes. Obviously this is an optical illusion, because her eyes haven’t moved for five hundred years, so just to be sure move your finger back and forth between the two positions a few times. Also, move your body slowly horizontally left and right a few inches. Then take your finger away and look at her other eye. Slowly look from one eye to the other, looking deep into the black pupil. It gets weirder the longer you look.

You can also get this optical illusion in living people by reproducing the setting. Get some soft light to one side, having your subject turn their head slightly in the direction of the light, and then have them look at your ear on the opposite side from the light. Have them stare at that ear for at least fifteen seconds, while you look carefully at their eyes, as in the picture above. When I do this I get that strange Mona Lisa effect.

What seems to be happening is the mind wants to believe that someone who is looking near you, is looking at you. It’s the mind’s way of preparing for what may come from that individual. It may be from a predator or an unfriendly person, but in any case the mind is taking no chances and assumes their eyes are on yours. The mind is prepared by evolution to react this way, and thus forms an illusion that it is so.

You can generate the Mona Lisa optical illusion in living people.

[ Added April 9, 2016 – When looking at the (clicked on to expand) image of Mona Lisa on a 25 inch screen, she becomes life size, and it makes a difference how close to the screen my face is when viewing her. When I am more than three feet back she is looking over my right shoulder, but when I am closer than one foot from the screen she is looking into my right eye. That is her right eye, (on my left) is looking into my right eye, but her left eye is also looking into my right eye. As I move from being close to the screen then to further and further back her gaze shifts from my eye to further to my right side, and further into the distance behind me. And, as I come close she shifts her gaze back into my eyes. As I repeat doing this, there is a time, while I’m moving back and forth, closer and further, where she is looking inside of me and thus at the back into my head. This is the time when I get the most willies, because she seems to be looking inside of my mind, and knows my inmost secrets. She is mysterious herself, but she seems to know everything about everything, and everybody, and me.]