3D Vision Is More Important than You Think

Dr. Russel Lazarus, July 11, 2021

According to i-Perception Magazine, 32% of the population has difficulties with 3D vision.

Do you have difficulties with judging distances or depth? 

Does your car have a few too many bumps and dents?

Difficulties with 3D vision and depth perception could be due to an undiagnosed lazy eye.

Stereopsis, more commonly known as 3D depth perception, occurs when your brain combines the two images received from each eye and creates one single 3D image. This allows you to easily engage and interact with the world around you.

What is stereopsis?

Stereopsis is the visual ability to see your surroundings in three dimensions (3D), allowing a person to judge the distance between themselves and objects around them. Poor stereopsis could indicate a serious eye condition, known as Amblyopia (lazy eye) 

Stereopsis and 3D vision are essential for driving, playing sports and contribute to a high quality of life. 

Depth perception arises from a variety of visual stimuli known as depth cues. They fall into two categories: monocular cues (single-eye) and binocular (two-eye) cues.

Monocular cues include:

  • Aerial perspective
  • Lighting and shading
  • Linear perspective
  • Overlap
  • Relative object size

Binocular cues include:

  • Fusion
  • Parallax

Types of stereopsis

There are two types of stereopsis – coarse stereopsis and fine stereopsis.

Coarse stereopsis, also known as gross stereopsis, provides the sense of being immersed in one’s surroundings. It’s important for orientation in space while moving.

Fine stereopsis is often what is tested in an eye exam – this is, very fine amounts of depth between objects. It’s important for fine-motor tasks such as threading a needle.

Signs of stereopsis problems

The signs and symptoms associated with poor or reduced stereopsis a similar to those of lazy eye and include:

  • Inaccurate depth judgment
  • Poor eye-hand coordination
  • Motion sickness
  • Asthenopia (eye strain)
  • Clumsiness
  • Difficulty concentrating or paying attention
  • Diplopia (double vision)
  • Dizziness/vertigo
  • Tendency to cover or close one eye

If you or your child experiences any of the above symptoms, contact an eye doctor near you

SEE RELATED: Does Amblyopia (Lazy Eye) Affect Eye-Hand Coordination?

Find an eye doctor near you

How does stereopsis impact daily life?

Here are some examples of how poor depth perception may create some challenges in your life:

1. Learning

Poor stereopsis can make learning difficult for some children.

A child may have a lazy eye or double vision, impacting their vision of the board, books or other teaching materials at school. 

Children may not have the ability to articulate their visual problem, or may not know that a problem exists.  If you notice them moving their head or squinting in an effort to try to get a better view, the problem could be their vision. .

2. Driving

Having poor stereopsis means that a driver might be unable to tell the distance between their car and other cars, or from the back of their car to the curb.

If you have a tendency to bump your car into objects around you, it is most likely a difficulty with stereopsis. 

While you probably can still drive, you may need to use some strategies to help you drive safely.

3. Sports

In sports, accurate depth perception helps players gauge the distance between themselves and a basketball hoop or home plate.

Stereopsis is also crucial to judge the flight of a ball or the movement of players around you.

Consider depth perception needed in baseball: accurate depth perception is vital when the batter needs to identify the difference between a fastball and a curveball, or for an outfielder making the game-winning catch.

4. Daily Tasks

Clear stereopsis also helps people perform simple, everyday tasks, like crossing a busy street safely or walking down a flight of stairs without the risks of misjudgment.

Daily activities as simple as driving, pouring a glass of milk or pruning a plant can be challenging with poor stereopsis.

If you believe that your depth perception is impaired, contact an eye doctor near you.

What causes stereopsis problems?

There are a number of factors that can contribute to problems with depth perception.

Some of the most common causes of reduced stereopsis are:

  1. Amblyopia (lazy eye): the condition causes the brain to favor one eye over the other, resulting in one eye that doesn’t quite track properly. Amblyopia may cause vision loss in the weaker eye, reducing depth perception.
  2. Blurry vision: There are dozens of potential causes of blurry vision, from eye emergencies, glaucoma and corneal abrasions to nearsightedness and diabetic retinopathy. Any condition that causes blurry vision, even temporarily, can interfere with your ability to perceive distances and depth accurately.
  3. Nerve conditions: If your optic nerve is swollen or inflamed, it might interfere with your depth perception and affect your vision.
  4. Strabismus (eye turns): This condition occurs when your eyes are misaligned, causing your eyes to look in slightly different directions, making you focus on different things.
  5. Trauma to one of your eyes: You may not be able to see well enough to have strong depth perception if one of your eyes has been injured.

How to improve stereopsis?

The most effective way to improve stereopsis is with Vision Therapy for Lazy Eyes.

Vision therapy teaches the eyes how to work together. For individuals whose poor stereopsis is caused by strabismus or amblyopia (lazy eye), vision therapy can help them regain good depth perception.

Vision therapy utilizes a combination of eye exercises, prisms and/or patching that can help a person regain good depth perception.

LEARN MORE: Vision Therapy for Lazy Eye

If your child has difficulties with depth perception, schedule an appointment with an eye doctor near you, they may have an undiagnosed lazy eye.