THE eyes are windows to the soul. What could be more obvious? I look through my eyes on to the world, and I look through the eyes of others into their minds.We immediately see the tenderness and passion in a loving gaze, the fear and malice in a hostile glance. In a lecture room, with hundreds of students, I can pick out exactly who is, and isn’t, paying attention. And, of course, there is the electricity of meeting a stranger’s glance across a crowded room.
But wait a minute; eyes are balls of jelly set in holes at the top of a skull. How could those glistening little marbles possibly tell me about love or fear or attention?
A new study in the Proceedings of the National Academy of Science suggests that our understanding of eyes emerges very early. Human eyes have much larger white areas than the eyes of other animals and so are easier to track. When most people, including tiny babies, look at a face, they concentrate on the eyes. People with autism often don’t pay attention to eyes in the same way, and have trouble meeting or following another person’s gaze. All this suggests that we may be adapted to figure out what our fellow humans feel from their eyes.
If that’s true, even very young babies may detect emotions from eyes, especially eye whites.
The researchers, Sarah Jessen of the Max Planck Institute and Tobias Grossmann of the University of Virginia, showed seven-month-old babies schematic pictures of eyes.
The eyes could be fearful or neutral; the clue to the emotion was the relative position of the eye whites. (Look in the mirror and raise your eyelids until the white area on top of the iris is visible, then register the look of startled fear on your doppelganger in the reflection.) The fearful eyes could look directly at the baby or look off to one side.
As a comparison, the researchers also gave the babies exactly the same images to look at but with the colours reversed, so that the whites were black. They showed the babies the images for only 50 milliseconds, too briefly even to see them consciously. They used a technique called event-related brain potentials, or ERP, to analyse the babies’ brainwaves.
The babies’ brainwaves were different when they looked at the fearful eyes and the neutral ones, and when they saw the eyes look right at them or off to one side. The differences were particularly clear in the frontal parts of the brain. Those brain areas control attention and are connected to the brain areas that detect fear.
When the researchers showed the babies the reversed images, their brains didn’t differentiate between them. So they weren’t just responding to the visual complexity of the images; they seemed to recognise that there was something special about the eye whites.
So perhaps the eyes are windows to the soul after all. I think that I just look out and directly see the table in front of me. But, in fact, my brain is making incredibly complex calculations that accurately reconstruct the shape of the table from the patterns of light that enter my eyeballs. My baby granddaughter Georgiana’s brain, nestled in the downy head on my lap, does the same thing.
The new research suggests that my brain also makes my eyes move in subtle ways that send out complex signals about what I feel and see. And, as she gazes up at my face, Georgie’s brain interprets those signals and reconstructs the feelings that caused them. She really does see the soul behind my eyes, as clearly as she sees the table in front of them.
By Alison Gopnik
With thanks to The Australian