What is Vision? What is Seeing? 

My wife, Sarah, and I are out for a Sunday drive. Our two dogs, Fred and Pliny, are in the back seat, napping away. I suddenly swerve to the left! I somehow realized the car next to me was drifting into my lane! 

I didn’t consciously “see” the car until after my quick reaction. 

How did this happen? I perceived the car next to me in my peripheral vision. Peripheral vision is a broad view of seeing that allows us to see what is not in our direct line of vision. You are reading this article on your computer or mobile device. While looking at the screen, expand your attention and notice what you can “see” to your left and right without moving the eyes to the sides. That is your peripheral vision. It’s not very clear, but your brain takes in a lot of information about what is happening around you and responds to it. 

The Many Functions of the Eyes

The eyes see, take in sensory information, anchor us in time, express emotions, organize our movement, and are part of our thinking. This article will primarily focus on the actions of the eyes related to seeing. 

What is seeing?

Seeing is the part of our visual process of which we are the most conscious. Seeing is also the part of our visual system about which we are most concerned. What concerns us most is our visual clarity.

Seeing is our ability to focus our eyes and “see” details near and far. We need to see to read, drive, do up-close detailed work, and see something off in the distance. 

Optometrists and ophthalmologists use the Snellen Chart to measure this ability. You read the letters on the chart’s lines when you get your eyes examined. If you can read the lines, you have good eyesight. If not, you get a prescription for corrective lenses. 

What is the Vision?

Vision is the part of our visual processing of which we are the least aware. Most of our visual processing takes place primarily outside our conscious awareness.

Here are some examples of unconscious visual processing:

• As I mentioned earlier, Peripheral vision is not usually in our conscious awareness unless we invoke it or something demands our attention.
• The eyes anchor us in time. Exposing the eyes to light and dark sets our circadian rhythms in a 24-hour cycle. This cycle affects our behavior and our physical and emotional states.
• The eyes make movements when we think. Daniel Kahneman notes that the pupils dilate when doing challenging math (32x63). With simple math (2+2), there is no change in dilation.
• Turning light into visual images—the process of seeing. Light hits the eyes, and the eyes send that sensory information in the form of electrical impulses to your brain. Your brain turns these electrical impulses into what we know as visual perception.
• The movements of the eyes are another aspect of the visual system of which most people are unaware. There are four types of movements the eyes make. Like we have habits in our other bodily activities, we have habits in moving the eyes. We can move our eyes easily in some directions but not others. These habits can enhance or limit our ability to tap into the potential of our visual system. 

The Four Primary Movements of the Eyes:

Let’s take this one aspect of our visual process—the primary movement of the eyes—and explore it. By becoming aware of the actions of the eyes and working with them, we can improve their functioning. Just like you were able to widen your awareness into your peripheral vision a few paragraphs ago. This translates into enhanced seeing, more accessible head, neck, and shoulder movements, and better orientation.

1. Saccades

Saccades are jumping movements of the eyes. When you move the eyes, they jump from object to object. 

Because the muscles of the eyes interplay with the neck muscles, you will find these saccades can create rough or jerky movements of the head, neck, shoulders, and back.

2. Smooth Tracking Movements

Smooth Tracking Movements (or Smooth Pursuit Movements) are movements of the eyes when tracking an object moving through space. When my dog runs through the yard, I can keep my eyes on him as I track his movements. Smooth tracking movements can be difficult as the eyes can habituate to saccading and not follow smooth movements through space. 

Smooth tracking movements of the eyes translate into smooth movements of the head, neck, shoulders, and back.

3. Convergence / Divergence

Convergence / Divergence (or Accommodation) is the ability of the eyes to focus near and far. 

As you move the finger closer, you might notice that your head drops a little. And as you move your finger away, your head lifts a little. When you do a lot of close-up work, your head tends to lower. This engages the flexors (the muscles that bend our joints and other body parts primarily in front of us like the abdomen and the bicep). When you shift your focus out in front, like when you move your finger away, you engage the extensors (the muscles that open our joints primarily in the back of us like the muscles along the spine and the triceps). 

The issue is that too much close-up work keeps us in a flexed position. We can get habituated to this posture which is also associated with internal processing (self-talk and internal feelings) and is a cause of myopia—nearsightedness. 

When you move your focus to the distance, your attention moves outward. You move into an external sensing mode.

Having the ability to smoothly and efficiently converge and diverge the eye for close-up and distance seeing is essential to our overall health.

4. Vestibulo-ocular

Vestibulo-ocular movements stabilize the eyes relative to the external world. When you walk, run and make other movements, this process compensates for head movements, keeping the external world relatively stable.

Being able to separate the eyes from the movement of the head is essential for balance and orientation. It has profound implications for the neck, back, and shoulders tonus. 

Conclusion

We can see from the explorations above that the movements of the eyes affect your entire muscular system and your orientation. The eyes are involved in every aspect of our daily functioning. When you improve the actions of the eyes, you improve the movements related to your overall abilities. 

After doing the explorations above, how are you feeling? How do your eyes feel? How is your peripheral vision? Stand up and walk around. Look at things near and far. Is this different from usual?

References:

Aldous Huxley, et al. Art of Seeing. London, Flamingo An Imprint Of Harpercollins Publishers, 1994.

Heggie, Jack. Total Body Vision. 1997. Longmont, CO, Genesis II Publishing, Inc., 2001.

Huberman, Andrew. “The Science of Vision, Eye Health & Seeing Better.” Huberman Lab, Andrew Huberman, 14 June 2021, hubermanlab.com/the-science-of-vision-eye-health-and-seeing-better/. Accessed 27 Jan. 2022.

Kahneman, Daniel. Thinking, Fast and Slow. New York, Farrar, Straus, And Giroux, 2011.