What Causes Tunnel Vision?

If you’ve ever noticed that you have severely reduced peripheral vision, but your central vision remains clear, you may be dealing with tunnel vision. This condition appears as though you’re looking at things through a long tube or a tunnel as if you can’t see anything in your peripheral vision.

Tunnel vision occurs because the cells in your eyes responsible for peripheral vision have become inhibited in some way. Whether this is due to stress, an eye condition, or some other medical condition, tunnel vision can be frustrating and a hindrance to your daily life.

An optometrist can help discover the root cause of your tunnel vision, beginning with a comprehensive eye exam.

What Is Tunnel Vision?

Imagine your eye as if it’s a camera that’s constantly taking images of everything around you. When you look around, you can see a wide field of view, almost as if you’re looking at a large framed picture. Sometimes, you can’t actually see the full picture—just the central part of it.

This is called “tunnel vision.” When you’re experiencing tunnel vision, you can only see a small part of what you should, like you’re looking at the big picture through a narrow tunnel. Everything that isn’t clearly visible through the tunnel is blurry, invisible, or faded. It’s like you can only see one small part when you know that your eye should be seeing something more.

This condition is common, but it shouldn’t occur often in your daily life. If you’re experiencing tunnel vision on a regular basis it’s a good idea to schedule an appointment with your eye doctor.

Why Does Tunnel Vision Happen?

When your eyes are seeing things clearly, it’s part of a complex process. Light rays enter through the clear front part of your eye, and due to how the eye is shaped, they’re bent and refracted to reach a singular focal point on the retina—the light-sensitive tissue at the back of the eye.

This retina primarily has two cells that help it receive light: rods and cones. The cones are heavily concentrated in the center of your retina in an area called the macula. Here, they help you with clear, sharp central vision. The rest of your retina is covered in rods, which help your retina build an image of what’s in your peripheral vision.When you’re experiencing certain medical conditions—whether in the eye or in another part of your body—these rods become inhibited. This stops them from clearly building an image of your environment and causes your field of view to be significantly smaller. 

Stress & Tunnel Vision

In some situations, tunnel vision isn’t caused by the rods being damaged or affected by some conditions. In periods of severe or prolonged stress or anxiety, many people notice that it almost seems like their vision is zoomed in, causing a similar effect to tunnel vision.

This is due to the body’s natural response to threat or danger—your “fight or flight” response. Many of your senses seem amplified, and your pupils dilate to take in more visual information. And when tunnel vision occurs due to this response, it’s due to your brain focusing to an extreme degree on what it believes could be threatening you or setting off the fight or flight response.

This intense focus is extremely similar to tunnel vision. Your field of view tightens, you’re more focused on central things, and you receive almost no peripheral vision, so you aren’t distracted. However, this isn’t a prolonged occurrence and goes away once your brain relaxes.

What Could Be Causing Tunnel Vision? 

There isn’t one singular answer to what causes tunnel vision. There is a wide range of eye conditions that can affect the rods in your eyes and inhibit how they function. These can include:

• Glaucoma
• Diabetic retinopathy (damage to the eyes caused by diabetes)
• Retinal detachment
• Optic neuritis (when your optic nerve becomes inflamed) 
• Retinitis pigmentosa (a group of medical conditions that directly affect the retina and damage your peripheral vision)

It isn’t just related to the eye, though. There are even medical conditions or disorders that can lead to developing tunnel vision. These include:

• Chronic stress
• Migraines
• Strokes
• Concussions or other trauma to the skull or eyes
• Hypertension (high blood pressure)
• Carotid artery disease
• Hypoglycemia

In some situations, tunnel vision can even be caused due to traveling at an extremely high speed, like when in a plane or on a roller coaster. This is often due to how blood flow becomes restricted at higher speeds and may alter how your eyes receive blood flow. 

Is Tunnel Vision Serious?

If you find yourself commonly experiencing tunnel vision, you should visit your optometrist for a comprehensive eye exam. They can perform a thorough examination of your eyes and see if there may be an optical condition causing you to experience tunnel vision.

However, if an optometrist determines that you don’t have an eye condition that could be causing your tunnel vision, you should seek medical attention to further determine the cause.

What to Do if You Experience Tunnel Vision

If you experience tunnel vision on a regular basis, you should schedule an eye exam with your optometrist or ophthalmologist to receive a professional diagnosis. Tunnel vision, though common, can be caused by many different factors, and it can be difficult to figure it out on your own. At Seal Beach Eyes, our team of trained eye care professionals is here to help. To learn more about tunnel vision or to receive a comprehensive eye exam, book an appointment with us today.