What Is Vision? What Is Seeing? How Eye Movements Influence Posture, Balance, and Movement

By Al Wadleigh, GCFP

Article Summary

Vision and seeing are not the same thing. Seeing refers to visual clarity and conscious focus, while vision includes the unconscious processes that organize movement, balance, orientation, peripheral awareness, and perception. In this article, we explore the difference between vision and seeing, examine the four primary movements of the eyes, and discover how improving eye movement can enhance posture, coordination, balance, and overall functioning.

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. Somehow, I realized that the car next to me was drifting into my lane.

I did not consciously “see” the car until after I reacted.

How did this happen? I perceived the car in my peripheral vision. Peripheral vision gives us a broad field of awareness beyond our direct line of sight. As you read this article on a computer or mobile device, continue looking at the screen while expanding your attention. What can you notice to your left and right without moving your eyes toward the sides? That is your peripheral vision.

The details may not be clear, yet your brain is still taking in information about what is happening around you and responding to it.

The Many Functions of the Eyes

The eyes help us see, take in sensory information, orient ourselves in space and time, express emotion, organize movement, and participate in thinking. This article focuses primarily on the actions of the eyes related to seeing.

What Is Seeing?

Seeing is the part of visual processing of which we are most conscious. It is also the part about which we are usually most concerned, especially when we think about visual clarity.

Seeing includes the ability to focus the eyes and distinguish details at different distances. We depend on this ability when we read, drive, do detailed close-up work, or look at something far away.

Optometrists and ophthalmologists use a Snellen chart to measure visual acuity. It is the familiar chart with rows of letters that become progressively smaller. The examination helps determine whether corrective lenses may improve the clarity of your eyesight.

What Is Vision?

Vision includes much more than the details we consciously see. A great deal of visual processing takes place outside conscious awareness.

Here are several examples:

• Peripheral vision usually remains in the background until we deliberately attend to it or something attracts our attention.
• Exposure to light and darkness helps regulate the circadian rhythm that organizes our approximately 24-hour sleep-and-wake cycle.
• The eyes also change while we think. Daniel Kahneman described how the pupils can dilate during a demanding mental calculation while remaining comparatively unchanged during a simple one.
• Light entering the eyes is converted into neural signals. The brain processes those signals as the visual experience through which we recognize people, objects, movement, color, depth, and spatial relationships.
• The eyes make several kinds of movement that most of us rarely notice. As with other activities, we may develop habits that make some directions or combinations easier than others. Becoming aware of those habits gives us an opportunity to explore a wider range of possibilities.

Four Primary Movements of the Eyes

Let us explore four kinds of eye movement. The aim is not to force or stretch the eyes. It is to notice how the eyes move, where the movement feels easy, and how movement of the eyes relates to the head, neck, shoulders, and the rest of you.

Keep each exploration small, slow, and comfortable. Rest whenever you wish. If an exploration causes eye pain, marked dizziness, or unusual visual symptoms, stop and consult an appropriate eye-care or healthcare professional.

1. Saccades

Saccades are quick movements that shift the eyes from one point of interest to another. When we scan a room or read a line of text, the eyes do not usually glide at a constant speed. They move in a series of small jumps and pauses.

Movements of the eyes, head, and neck are closely coordinated. If the eyes habitually move with more effort in one direction, you may notice corresponding effort or jerkiness in the head, neck, shoulders, or back.

Try this: Look from left to right and then from right to left. Let your gaze travel across the room. Notice how the eyes jump from one object or detail to another. When you read, can you sense the smaller saccades that carry your gaze from word to word or phrase to phrase?

The eyes also make tiny, involuntary movements called microsaccades, even when the gaze seems steady. These movements contribute to the continuing visibility of a stationary scene and help counter perceptual fading.

2. Smooth Tracking Movements

Smooth tracking, also called smooth pursuit, occurs when the eyes follow an object moving through space. When my dog runs through the yard, for example, I can keep my eyes on him as I follow his movement. If the eyes are accustomed to shifting in saccades, following a slowly moving object smoothly may be surprisingly difficult.

As you explore smooth tracking, notice whether greater ease in the eyes is accompanied by greater ease in the head, neck, shoulders, and back.

Try this: Bring one hand in front of your face at about arm’s length, with the index finger pointing upward. Move your hand and arm slowly from side to side while following the fingertip with your eyes. Can you keep your gaze on the finger? Are there places where the eyes jump or seem to get stuck? Does the movement feel smoother in some areas than in others?

3. Convergence and Divergence

Convergence and divergence describe how the eyes turn inward or outward as attention shifts between nearer and farther objects. These coordinated movements work together with accommodation, the process by which the lens changes focus.

Try this: Hold your index finger in front of your face at a comfortable distance. Slowly bring it closer to your nose while keeping it in comfortable focus. The eyes converge, moving inward toward the finger. Then move the finger away again and notice the eyes diverging. Can you follow the finger smoothly? Do the eyes jump at any point? Is there a distance at which the movement becomes less comfortable or less clear?

As the finger comes closer, you may notice the head lowering slightly. As the finger moves away, the head may lift. Close-up work often brings us toward flexion, involving muscles at the front of the body. Looking into the distance may invite more extension through the spine and a broader orientation toward the environment.

Extended near work can become associated with a habitual posture and sustained visual effort. Nearsightedness itself has multiple influences and involves the shape of the eye; it should not be attributed to posture or close work alone. The useful question in this exploration is simpler: can you shift between near and far focus with less unnecessary effort?

4. Vestibulo-Ocular Movement

The vestibulo-ocular reflex helps stabilize the visual field while the head moves. When you walk, run, or turn your head, this system produces compensatory eye movements that help keep what you are looking at relatively steady.

The ability to let the head move while the eyes remain oriented toward a point is important for balance and spatial orientation. It also gives us a useful way to notice coordination among the eyes, neck, shoulders, and back.

Try this: Bring one arm in front of you with the index finger pointing upward. Keep the finger still and rest your gaze on it. Slowly turn your head a small distance to the left and right while continuing to look at the finger. Is the movement smooth? Can the head move without the eyes losing the fingertip? What happens in your neck, jaw, breathing, and shoulders?

What Do You Notice Now?

These explorations show that the movements of the eyes participate in larger patterns of orientation and movement. Rather than treating the eyes as isolated from the rest of the body, we can notice how seeing, balance, posture, attention, and action continually influence one another.

After trying the explorations, pause for a moment. How do your eyes feel? Has your peripheral awareness changed? Stand and walk around. Look at objects that are near and far. Notice whether anything feels different from usual.

Continue Exploring Vision and Movement

Jack Heggie and I created Total Body Vision, an audio program that combines ideas from the Bates Method of vision improvement with Feldenkrais Method® movement education and Awareness Through Movement® lessons. Its guided explorations develop the relationships among eye movement, posture, orientation, and whole-body coordination.

Frequently Asked Questions

References

• Huxley, Aldous, et al. The Art of Seeing. Flamingo, 1994.
• Heggie, Jack. Total Body Vision. Genesis II Publishing, 2001.
• Huberman, Andrew. “The Science of Vision, Eye Health & Seeing Better.” Huberman Lab, 14 June 2021.
• Kahneman, Daniel. Thinking, Fast and Slow. Farrar, Straus and Giroux, 2011.

Photo Credit: Petri Heiskanen on Unsplash.